Difference between revisions of "Team:HZAU-China/Results"

Line 91: Line 91:
 
             z-index: 1;
 
             z-index: 1;
 
             background-color: #EEEEEE;
 
             background-color: #EEEEEE;
            opacity: 0.96;
 
            filter: alpha(opacity=96);
 
 
             box-shadow: 0 5px 15px #CCCCCC;
 
             box-shadow: 0 5px 15px #CCCCCC;
 
             display: none;
 
             display: none;
Line 154: Line 152:
 
         }
 
         }
  
         .daohang a:hover span{
+
         .daohang a:hover span {
             transform: rotateY(180deg);          
+
             transform: rotateY(180deg);
             -webkit-transform: rotateY(180deg);          
+
             -webkit-transform: rotateY(180deg);
             -moz-transform: rotateY(180deg);          
+
             -moz-transform: rotateY(180deg);
             -o-transform: rotateY(180deg);          
+
             -o-transform: rotateY(180deg);
 
             -ms-transform: rotateY(180deg);
 
             -ms-transform: rotateY(180deg);
             transition: all 0.5s ease-in-out;          
+
             transition: all 0.5s ease-in-out;
             -webkit-transition: all 0.5s ease-in-out;          
+
             -webkit-transition: all 0.5s ease-in-out;
             -moz-transition: all 0.5s ease-in-out;          
+
             -moz-transition: all 0.5s ease-in-out;
 
             -o-transition: all 0.5s ease-in-out;
 
             -o-transition: all 0.5s ease-in-out;
 
         }
 
         }
Line 244: Line 242:
  
 
             .daohangyi {
 
             .daohangyi {
                 font-size: 14px;
+
                 font-size: 12px;
 
             }
 
             }
 
         }
 
         }
Line 269: Line 267:
 
             .daohangyi img {
 
             .daohangyi img {
 
                 display: none;
 
                 display: none;
 +
            }
 +
 +
            .daohang .longName .item:before {
 +
                width: 150px;
 +
                left: 20px;
 +
            }
 +
 +
            .daohang .longName .item:hover:after {
 +
                width: 150px;
 +
                left: 20px;
 
             }
 
             }
 
         }
 
         }
Line 292: Line 300:
 
             width: 80%;
 
             width: 80%;
 
             /* height: auto; */
 
             /* height: auto; */
             margin: 20px 20px 0 0;
+
             margin: 20px 40px 0 0;
 
             /* right: 2%; */
 
             /* right: 2%; */
 
             /* top: 90px; */
 
             /* top: 90px; */
             padding: 20px 3%;
+
             padding: 50px 3%;
 
             float: right;
 
             float: right;
 
             /* position: relative; */
 
             /* position: relative; */
Line 308: Line 316:
  
 
         .cebian {
 
         .cebian {
             width: 15%;
+
             width: 200px;
 
             /* height: 80vh; */
 
             /* height: 80vh; */
 
             float: left;
 
             float: left;
Line 317: Line 325:
 
             /* border:2px solid black */
 
             /* border:2px solid black */
 
             /* background-color: #323643 */
 
             /* background-color: #323643 */
 +
        }
 +
 +
        .zhengwen p{
 +
            text-align: justify !important;
 +
            font-family:  'Times New Roman',Helvetica,'Open Sans',  Arial, sans-serif !important;
 +
            color: #3B3B3B;
 +
            font-size: 26px !important;
 +
            padding-right: 20px;
 
         }
 
         }
  
Line 327: Line 343:
  
 
         .h1 {
 
         .h1 {
            height: 100px;
+
             line-height: 55px;
             line-height: 100px;
+
 
             font-weight: bold;
 
             font-weight: bold;
 +
            height:auto;
 
             font-family: 'Product Sans', sans-serif;
 
             font-family: 'Product Sans', sans-serif;
             font-size: 50px;
+
             font-size: 40px;
             color: black;
+
             color: #3B3B3B;
             border-bottom: 3px solid black;
+
             border-bottom: 2px solid #676767;
             /* margin: 0 2.4%; */
+
            margin-bottom: 20px;
 +
        }
 +
 
 +
        .h2 {
 +
            height: 40px;
 +
            line-height: 40px;
 +
            font-weight: bold;
 +
            height:auto;
 +
            /* font-weight: bold; */
 +
            font-family: 'Product Sans', sans-serif;
 +
            font-size: 30px;
 +
            color: #484848;
 +
             /* margin-bottom: 20px; */
 +
        }
 +
 
 +
        .h3 {
 +
            height: 30px;
 +
            line-height: 30px;
 +
            font-weight: bold;
 +
            height:auto;
 +
            /* font-weight: bold; */
 +
            font-family: 'Product Sans', sans-serif;
 +
            font-size: 24px;
 +
            color: #484848;
 +
            /* margin-bottom: 20px; */
 +
        }
 +
       
 +
        table {
 +
            color: #3B3B3B;
 
         }
 
         }
  
Line 450: Line 494:
 
     <style>
 
     <style>
 
         #float01 {}
 
         #float01 {}
 +
   
 +
            #float02 {}
  
        #float02 {}
+
            #float03 {}
  
        #float03 {}
+
            #float04 {}
  
        div.floatCtro {
+
             #float05 {}
             width: 100%;
+
            height: 250px;
+
            margin: 0;
+
            position: relative;
+
            background: #fff;
+
  
        }
+
             div.floatCtro {
 
+
                width: 100%;
        .daohangyi {
+
                /* height: auto; */
             display: block;
+
                margin: 0;
            width: 100%;
+
                position: relative;
            height: 40px;
+
                background: #fff;
            color: #ffffff !important;
+
   
            font-size: 16px;
+
             }
            background-color: #323643;
+
   
            border-bottom: 1px solid black;
+
            /* border-radius: 5px; */
+
            text-decoration: none !important;
+
        }
+
 
+
        div.floatCtro .daohanger {
+
            width: 100%;
+
            text-align: justify !important;
+
            height: 45px;
+
            line-height: 45px;
+
            font-family: Arial;
+
            font-size: 14px;
+
            color: #676767;
+
            margin: 0;
+
            padding-left: 8%;
+
            cursor: pointer;
+
            background: #fff;
+
        }
+
 
+
        div.floatCtro a {
+
            display: inline-block;
+
            display: none;
+
            width: 100%;
+
            height: 40px;
+
            /* margin: 10px 0 0 0; */
+
            background: #FFF;
+
            color: #000 !important;
+
            vertical-align: middle;
+
            cursor: pointer;
+
        }
+
 
+
        div.floatCtro a span {
+
            display: block;
+
            height: 44px;
+
            line-height: 44px;
+
            font-family: Arial;
+
            font-size: 16px;
+
            padding-left: 8%;
+
        }
+
 
+
        div.floatCtro a:hover {
+
            /* background: #76b39d; */
+
            color: #EA0D04 !important;
+
            zoom: 1;
+
        }
+
 
+
        /* .cebian a:hover {
+
            color: #f6eee0 !important;
+
        } */
+
 
+
        div.floatCtro .daohanger:hover {
+
            /* background: #76b39d; */
+
            color: #1fa67a;
+
             text-decoration: underline !important;
+
        }
+
 
+
        div.floatCtro .daohanger.cur {
+
            /* background: #1fa67a; */
+
            color: #1fa67a;
+
        }
+
 
+
        .biaoti {
+
            line-height: 40px;
+
            width: 50%;
+
            margin-left: 6%;
+
            text-align: center;
+
            text-decoration: none !important;
+
        }
+
 
+
        .daohangyi img {
+
            display: inline-block;
+
            width: 12px;
+
            height: 12px;
+
            vertical-align: middle;
+
            background-size: 100% 100%;
+
 
+
        }
+
        .cebian div:hover img{
+
            transform: rotateY(180deg);           
+
            -webkit-transform: rotateY(180deg);           
+
            -moz-transform: rotateY(180deg);           
+
            -o-transform: rotateY(180deg);           
+
            -ms-transform: rotateY(180deg);
+
            transition: all 0.5s ease-in-out;           
+
            -webkit-transition: all 0.5s ease-in-out;           
+
            -moz-transition: all 0.5s ease-in-out;           
+
            -o-transition: all 0.5s ease-in-out;
+
        }
+
        .cebian a:hover img{
+
            transform: rotate(360deg);           
+
            -webkit-transform: rotate(360deg);           
+
            -moz-transform: rotate(360deg);           
+
            -o-transform: rotate(360deg);           
+
            -ms-transform: rotate(360deg);
+
            transition: all 0.5s ease-in-out;           
+
            -webkit-transition: all 0.5s ease-in-out;           
+
            -moz-transition: all 0.5s ease-in-out;           
+
            -o-transition: all 0.5s ease-in-out;
+
        }
+
 
+
        @media screen and (max-width: 1000px) {           
+
         
+
 
             .daohangyi {
 
             .daohangyi {
                 font-size: 14px;
+
                display: block;
 +
                width: 100%;
 +
                /* height: auto; */
 +
                /* text-align: left !important; */
 +
                color: #ffffff !important;
 +
                 font-size: 16px;
 +
                padding:0;
 +
                background-color: #323643;
 +
                border-bottom: 1px solid black;
 +
                padding:0 3%;
 +
                text-decoration: none !important;
 
             }
 
             }
        }
+
   
 
+
            div.floatCtro .daohanger {
        @media screen and (max-width: 880px) {
+
                width: 100%;
 
+
                text-align: left !important;
 +
                height: auto;
 +
                line-height: 25px;
 +
                font-family: Arial;
 +
                font-size: 14px !important;
 +
                color: #676767;
 +
                margin: 0;
 +
                padding:10px 8%;
 +
                cursor: pointer;
 +
                background: #fff;
 +
            }
 +
   
 +
            div.floatCtro a {
 +
                display: inline-block;
 +
                display: none;
 +
                width: 100%;
 +
                height: 40px;
 +
                padding:10px 8%;
 +
                /* margin: 10px 0 0 0; */
 +
                background: #FFF;
 +
                color: #000 !important;
 +
                vertical-align: middle;
 +
                cursor: pointer;
 +
            }
 +
   
 +
            div.floatCtro a span {
 +
                display: block;
 +
                height: auto;
 +
                text-align: left !important;
 +
                line-height: 18px;
 +
                font-family: Arial;
 +
                font-size: 16px;
 +
            }
 +
   
 +
            div.floatCtro a:hover {
 +
                /* background: #76b39d; */
 +
                color: #EA0D04 !important;
 +
                zoom: 1;
 +
            }
 +
   
 +
            /* .cebian a:hover {
 +
                color: #f6eee0 !important;
 +
            } */
 +
   
 +
            div.floatCtro .daohanger:hover {
 +
                /* background: #76b39d; */
 +
                color: #1fa67a;
 +
                text-decoration: underline !important;
 +
            }
 +
   
 +
            div.floatCtro .daohanger.cur {
 +
                /* background: #1fa67a; */
 +
                color: #1fa67a;
 +
            }
 +
   
 +
            .biaoti {
 +
                display: inline-block;
 +
                margin: 8px 0;
 +
                /* width: 50%; */
 +
                /* margin-left: 6%; */
 +
                /* text-align: center; */
 +
                text-decoration: none !important;
 +
            }
 +
   
 
             .daohangyi img {
 
             .daohangyi img {
 +
                display: inline-block;
 +
                width: 12px;
 +
                height: 12px;
 +
                vertical-align: middle;
 +
                background-size: 100% 100%;
 +
   
 +
            }
 +
            .cebian div:hover img{
 +
                transform: rotateY(180deg);           
 +
                -webkit-transform: rotateY(180deg);           
 +
                -moz-transform: rotateY(180deg);           
 +
                -o-transform: rotateY(180deg);           
 +
                -ms-transform: rotateY(180deg);
 +
                transition: all 0.5s ease-in-out;           
 +
                -webkit-transition: all 0.5s ease-in-out;           
 +
                -moz-transition: all 0.5s ease-in-out;           
 +
                -o-transition: all 0.5s ease-in-out;
 +
            }
 +
            .cebian a:hover img{
 +
                transform: rotate(360deg);           
 +
                -webkit-transform: rotate(360deg);           
 +
                -moz-transform: rotate(360deg);           
 +
                -o-transform: rotate(360deg);           
 +
                -ms-transform: rotate(360deg);
 +
                transition: all 0.5s ease-in-out;           
 +
                -webkit-transition: all 0.5s ease-in-out;           
 +
                -moz-transition: all 0.5s ease-in-out;           
 +
                -o-transition: all 0.5s ease-in-out;
 +
            }
 +
   
 +
            @media screen and (max-width: 1200px) {           
 +
             
 +
                .cebian {
 +
                width: 15%;
 +
                }
 +
   
 +
                .zhengwen {
 +
                margin: 20px 20px 0 0;
 +
   
 +
                .daohangyi {
 +
                    font-size: 14px;
 +
                }
 +
                .daohangyi img {
 +
                    display: none;
 +
                } 
 +
            }
 +
   
 +
            @media screen and (max-width: 900px) {
 +
   
 +
                .daohangyi img {
 +
                    display: none;
 +
                } 
 +
               
 +
                .laoshi img {
 +
                    height: 30vh;
 +
                }
 +
            }
 +
    </style>
 +
    <!-- 折叠框CSS -->
 +
    <style>
 +
        .collapseDiv {
 +
              color: #333;
 +
              border-radius: 4px;
 +
              background-color: #F3F3F3;
 +
              border: 1px solid transparent;
 +
              border-color: #ddd;
 +
              box-shadow: 0 1px 1px #F3F3F3;
 +
              margin-top: 5px;
 +
              margin-bottom: 0;
 +
            }
 +
            .collapseDiv label {
 +
              cursor: pointer;
 +
              font-size: 24px  !important;
 +
              /* font-weight: bold; */
 +
              color: green  !important;
 +
              border-color: #F3F3F3  !important;
 +
              padding: 5px 15px 5px 18px  !important;
 +
              background-color: #f5f5f5  !important;
 +
              margin: 0  !important;
 +
              border-radius: 5px  !important;
 +
            }
 +
   
 +
            #zhedie-toggle1,
 +
            #zhedie-toggle2,
 +
            #zhedie-toggle3,
 +
            #zhedie-toggle4,
 +
            #zhedie-toggle5,
 +
            #zhedie-toggle6,
 +
            #zhedie-toggle7 {
 
                 display: none;
 
                 display: none;
             }
+
             }
 +
   
 +
            #zhedie1,
 +
            #zhedie2,
 +
            #zhedie3,
 +
            #zhedie4,
 +
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 +
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 +
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 +
   
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            #zhedie-toggle1:checked+#zhedie1,
 +
            #zhedie-toggle2:checked+#zhedie2,
 +
            #zhedie-toggle3:checked+#zhedie3,
 +
            #zhedie-toggle4:checked+#zhedie4,
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            #zhedie-toggle5:checked+#zhedie5,
 +
            #zhedie-toggle6:checked+#zhedie6,
 +
            #zhedie-toggle7:checked+#zhedie7 {
 +
                display: block;
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 +
   
 
              
 
              
             .laoshi img {
+
   
                height: 30vh;
+
   
 +
             .collapse_body {
 +
              background-color: #fff;
 +
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     </style>
 
     </style>
  
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                 <a class="item" href="https://2018.igem.org/Team:HZAU-China/Experiments">Experiments</a>
 
                 <a class="item" href="https://2018.igem.org/Team:HZAU-China/Experiments">Experiments</a>
 
                 <a class="item" href="https://2018.igem.org/Team:HZAU-China/Improve">Improve</a>
 
                 <a class="item" href="https://2018.igem.org/Team:HZAU-China/Improve">Improve</a>
                 <a class="item" href="https://2018.igem.org/Team:HZAU-China/InterLab">Interlab</a>
+
                 <a class="item" href="https://2018.igem.org/Team:HZAU-China/InterLab">InterLab</a>
 +
                <a class="item" href="https://2018.igem.org/Team:HZAU-China/Notebook">Notebook</a>
 +
 
 
             </li>
 
             </li>
 
             <li class="hiLight shortName">
 
             <li class="hiLight shortName">
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                     <span class="xjtPic"></span>
 
                     <span class="xjtPic"></span>
 
                 </a>
 
                 </a>
                 <a class="item" href="https://2018.igem.org/Team:HZAU-China/Safety">Safty</a>
+
                 <a class="item" href="https://2018.igem.org/Team:HZAU-China/Safety">Safety</a>
 
                 <a class="item" href="https://2018.igem.org/Team:HZAU-China/Human_Practices">Human Practices</a>
 
                 <a class="item" href="https://2018.igem.org/Team:HZAU-China/Human_Practices">Human Practices</a>
 
                 <a class="item" href="https://2018.igem.org/Team:HZAU-China/Public_Engagement">Public Engagement</a>
 
                 <a class="item" href="https://2018.igem.org/Team:HZAU-China/Public_Engagement">Public Engagement</a>
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                 <a class="item" href="https://2018.igem.org/Team:HZAU-China/Collaborations">Collaborations</a>
 
                 <a class="item" href="https://2018.igem.org/Team:HZAU-China/Collaborations">Collaborations</a>
 
             </li>
 
             </li>
             <li class="shortName">
+
             <li class="hiLight shortName">
                 <a class="nav_head" href="https://2018.igem.org/Team:HZAU-China/Parts">
+
                 <a class="nav_head" href="#">
 
                     <span>Parts</span>
 
                     <span>Parts</span>
 +
                    <span class="xjtPic"></span>
 
                 </a>
 
                 </a>
 +
                <a class="item" href="https://2018.igem.org/Team:HZAU-China/Basic_Part">Basic</a>
 +
                <a class="item" href="https://2018.igem.org/Team:HZAU-China/Composite_Part">Composite</a>
 
             </li>
 
             </li>
 
         </ul>
 
         </ul>
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         <!-- 正文 -->
 
         <!-- 正文 -->
 
         <div class="zhengwen">
 
         <div class="zhengwen">
            <img class="daimg" src="https://static.igem.org/mediawiki/2018/7/70/T--HZAU-China--hezhao1.png" alt="">
 
 
             <div id="float01" class="cur">
 
             <div id="float01" class="cur">
                 <div class="h1">biaotiyi</div>
+
                 <div class="h1">Chassis</div>
 +
                <div class="h2"><i>sifA</i> knock out</div>
 +
                <p>SifA maintains the integrity of <i>Salmonella</i>-containing vacuole (SCV) where <i>Salmonella</i> survive and
 +
                    replicate<sup>1</sup>. The existence of SCV limits the releasing of GSDMD-N275 into cytoplasm. In addition,
 +
                    the growth of inhibition of Δ<i>sifA</i> mutant in macrophage is remarkable<sup>2</sup>. Thus, we knocked out the
 +
                    <i>sifA</i> gene in order to prevent the stability of SCV and reduce the virulence of <i>Salmonella</i>. </p>
 +
                <p>Δ<i>sifA</i> mutant was constructed by using gene editing system based on two-step allelic exchange<sup>3</sup>.</p>
 +
                <p>PCR verification indicated that chromosomal gene <i>sifA</i> was knocked out (Figure 1). Primers named
 +
                    DSIFA F and DSIFA R were used in this PCR (Figure 2).</p>
 +
                <div style="width: 40%; margin: 20px auto">
 +
                    <img src="https://static.igem.org/mediawiki/2018/7/79/T--HZAU-China--results1.png" width=100% alt="">
 +
                </div>
 +
                <p>Figure 1. PCR verification of <i>sifA</i> gene knock out. Lane 1 refers to mutant candidate. Lane 2 refers
 +
                    to WT <i>Salmonella enterica</i> var. Typhimurium SL1344 as a control.</p>
 +
                <div style="width: 90%; margin: 20px auto">
 +
                    <img src="https://static.igem.org/mediawiki/2018/0/07/T--HZAU-China--results2.png" width=100% alt="">
 +
                </div>
 +
                <p>Figure 2. DSIFA F and DSIFA R are the primers in the ORF of <i>sifA</i>. This pair of primers can extend a
 +
                    436bp product in WT.</p>
  
 +
                <div class="h2">Safety</div>
 +
                <p>SifA is essential for maintaining vacuolar membrane stability. Cytosolic bacteria can be generated
 +
                    by the function loss of <i>Salmonella</i>-containing vacuole (SCV). This population of bacteria was easily
 +
                    recognized and cleaned up by macrophage. Hence, Δ<i>sifA</i> mutant decrease the toxicity to the host.
 +
                    Microscopy demonstrated that Δ<i>sifA</i> mutant was defective for replication in macrophage (Figure 3).
 +
                </p>
 +
                <div style="width: 90%; margin: 0px auto">
 +
                    <img src="https://static.igem.org/mediawiki/2018/9/93/T--HZAU-China--results3.png" width=100% alt="">
 +
                </div>
 +
                <p>Figure 3. Microscopy of immortalized bone-marrow-derived macrophages (iBMDM) infected with the Δ<i>sifA</i>
 +
                    mutant and WT <i>Salmonella</i>, respectively. These strains contain a high copy number of plasmids to
 +
                    express RFP constitutively.</p>
 +
                <div class="collapseDiv">
 +
                    <label for="zhedie-toggle1">Method</label>
 +
                    <input type="checkbox" id="zhedie-toggle1" />
 +
                    <div id="zhedie1" class="text-success text-left">
 +
                        <b>Preparation of Cells for Infection</b><br>
 +
                        1. Grow iBMDMs in a humidified 37 °C, 5% CO<sub>2</sub> tissue-culture incubator.<br>
 +
                        2. Count the cells using a hemocytometer. Seed in 24-well (5 × 10^4 per well) and grow
 +
                        overnight .<br>
 +
                        <b>Preparation of Bacteria</b>
 +
                        1. Grow bacteria overnight 16 h in 2 mL LB in a 15-mL tube. Incubate at 37 °C in a shaking
 +
                        incubator (200 rpm).<br>
 +
                        2. Subculture bacteria by transferring 300 μL of the overnight culture into 5 mL of LB in a
 +
                        loosely capped 50-mL tube. Incubate at 37 °C in a shaking incubator (200 rpm) to late log
 +
                        phase.<br>
 +
                        3. Pellet 1 mL of the <i>Salmonella</i> subculture by centrifugation at 1000 g in a microfuge for 2
 +
                        min at room temperature.<br>
 +
                        4. Remove 900 μL of supernatant and gently resuspend the pellet in 900 μL PBS.<br>
 +
                        <b>Infection</b>
 +
                        1. Aspirate media and rinse the monolayer twice with PBS.<br>
 +
                        2. Inoculate cells with bacteria (MOI = 20) by adding bacteria directly to the cell-culture
 +
                        supernatant. Centrifugation at 110 g for 5 min at room temperature.<br>
 +
                        3. Incubate for 25 min at 37 °C in 5% CO<sub>2</sub>.<br>
 +
                        4. Aspirate media and rinse the monolayer twice with PBS, to remove extracellular bacteria.<br>
 +
                        5. Add fresh GM containing 100 μg/mL gentamicin and incubate for 2 h at 37 °C in 5% CO<sub>2</sub>.<br>
 +
                        6. Replace GM with fresh GM containing 20 μg/mL gentamicin for remainder of experiment.<br>
 +
                        Observation is taken after 11 h.<br><br>
 +
 +
                    </div>
 +
                </div>
 
             </div>
 
             </div>
 
             <div id="float02">
 
             <div id="float02">
                 <div class="h1">biaotier</div>
+
                 <div class="h1">Targeting</div>
 
+
                <p>RGD motif can specifically bind to alpha V beta 3 (αVβ3) a well-known biomarker on the surface of
 +
                    tumor cells. We express RGD motif fused with OmpA to surface display it on the outer membrane of
 +
                    bacteria. Microscopy shows that bacteria expressed Lpp-OmpA-RGD induced by 0.1 mM IPTG can bind to
 +
                    αVβ3-positive MDA-MB-231 cell line. The location of bacteria is pointed by red arrow (Figure 4).
 +
                    But cannot bind to αVβ3-negative MCF7 cell line (Figure 5). These results demonstrated that
 +
                    bacteria gain the function of tumor targeting though display RGD motif. </p>
 +
                <div style="width: 90%; margin: 0px auto">
 +
                    <img src="https://static.igem.org/mediawiki/2018/b/b1/T--HZAU-China--Improve2.png" width=100% alt="">
 +
                </div>
 +
                <p>Figure 4. Microscopy of αVβ3-positive MDA-MB-231 cell line were incubated with <i>E. coli</i> which
 +
                    constructive expressed RFP and inductive expressed RGD motif under the control of lac promoter. </p>
 +
                <div style="width: 90%; margin: 0px auto">
 +
                    <img src="https://static.igem.org/mediawiki/2018/c/cf/T--HZAU-China--Improve3.png" width=100% alt="">
 +
                </div>
 +
                <p>Figure 5. Microscopy of αVβ3-negative MCF7 cell line were incubated with <i>E. coli</i>  which constructive
 +
                    expressed RFP and inductive expressed RGD motif under the control of lac promoter.</p>
 +
                <div class="collapseDiv">
 +
                    <label for="zhedie-toggle2">Method</label>
 +
                    <input type="checkbox" id="zhedie-toggle2" />
 +
                    <div id="zhedie2" class="text-success text-left">
 +
                        <b>Preparation of Cells</b><br>
 +
                        1. Grow MDA-MB-231 and MCF7 in a humidified 37 °C, 5% CO<sub>2</sub> tissue-culture incubator.<br>
 +
                        2. Count the cells using a hemocytometer. Seed in 24-well (1.5× 10^5 per well) and grow
 +
                        overnight.<br>
 +
                        <b>Preparation of Bacteria</b>
 +
                        1. Grow bacteria overnight 14 h in 2 mL LB in a 15-mL tube. Incubate at 37 °C in a shaking
 +
                        incubator (200 rpm).<br>
 +
                        2. Subculture bacteria by transferring 300 μL of the overnight culture into 5 mL of LB
 +
                        containing 0.1 mM IPTG in a loosely capped 50-mL tube. Incubate at 37 °C in a shaking incubator
 +
                        (200 rpm) to early stationary phase.<br>
 +
                        3. Pellet 1 mL of the bacteria subculture by centrifugation at 1000 g in a microfuge for 2 min
 +
                        at room temperature.<br>
 +
                        4. Remove 900 μL of supernatant and gently resuspend the pellet in 900 μL PBS.<br>
 +
                        <b>Infection</b>
 +
                        1. Aspirate media and rinse the monolayer twice with PBS.<br>
 +
                        2. Inoculate cells with bacteria (MOI = 100) by adding bacteria directly to the cell-culture
 +
                        supernatant.<br>
 +
                        3. Incubate for 1.5 h at 37 °C in 5% CO<sub>2</sub>.<br>
 +
                        4. Aspirate media and rinse the monolayer three times with PBS.<br>
 +
                        Observation is taken immediately.<br><br>
 +
                    </div>
 +
                </div>
 
             </div>
 
             </div>
 
             <div id="float03">
 
             <div id="float03">
                 <div class="h1">biaotisan</div>
+
                 <div class="h1">Function of GSDMD</div>
                  
+
                 <div class="h2">The N-terminal of GSDMD performs the function of cell pyroptosis</div>
 +
                <p>We fused eGFP with GSDMD-N275 and GSDMD FL (full length), respectively. Then the corresponding
 +
                    plasmids were transfected into Hela GSDMD KO cell. Cell microscopy showed that the cells
 +
                    transfected with GSDMD-N275 underwent pyroptosis while the cells with GSDMD FL did not (Figure 6).
 +
                    We also tested the cell viability though an ATP assay (CellTiter-Glo® Luminescent Cell Viability
 +
                    Assay) and demonstrated that GSDMD-N275 and mutants of GSDMD FL have different ability to induce
 +
                    pyroptosis (Figure 7).</p>
 +
                <div style="width: 90%; margin: 0px auto">
 +
                    <img src="https://static.igem.org/mediawiki/2018/7/7b/T--HZAU-China--results6.png" width=100% alt="">
 +
                </div>
 +
                <p>Figure 6. Microscopy of the Hela GSDMD KO cells transfected with pCS2-eGFP-GSDMD FL and
 +
                    pCS2-eGFP-GSDMD-N275, respectively. Pyroptotic cells are pointed by red arrow.</p>
 +
                <div class="collapseDiv">
 +
                    <label for="zhedie-toggle3">Method</label>
 +
                    <input type="checkbox" id="zhedie-toggle3" />
 +
                    <div id="zhedie3" class="text-success text-left">
 +
                        <b>Preparation of Cells for transfection</b><br>
 +
                        1. Grow Hela GSDMD KO cells in a humidified 37 °C, 5% CO<sub>2</sub> tissue-culture incubator.<br>
 +
                        2. Count the cells using a hemocytometer. Seed in 24-well (5 × 10^4 per well) and grow.<br>
 +
                        <b>Transfection</b> <br>
 +
                        1. Dilute 0.5 μg DNA into 50 μl jetPRIME® buffer (supplied). Mix by vortexing.<br>
 +
                        2. Add 1 μl jetPRIME®, vortex for 10 s, spin down briefly.<br>
 +
                        3. Incubate for 10 min at RT.<br>
 +
                        4. Add 50μl of transfection mix per well drop wise onto the cells in serum containing medium,
 +
                        and distribute evenly.<br>
 +
                        5. Gently rock the plates back and forth and from side to side.<br>
 +
                        6. If needed, replace transfection medium after 4 h by cell growth medium and return the plates
 +
                        to the incubator.<br>
 +
                        Observation is taken after 1.5 h.<br><br>
 +
                    </div>
 +
                </div>
 +
                <div style="width: 50%; margin: 20px auto">
 +
                    <img src="https://static.igem.org/mediawiki/2018/f/f5/T--HZAU-China--basicPart2.png" width=100% alt="">
 +
                </div>
 +
                <p>Figure 7. Cell viability of the 293T cells transfected with pCS2-Flag-GSDMD FL,
 +
                    pCS2-Flag-GSDMD-N275, pCS2-Flag-GSDMD L290D, pCS2-Flag-GSDMD Y373D, pCS2-Flag-GSDMD A377D,
 +
                    respectively. Asterisks indicate the statistically significant differences. ATP-based cell
 +
                    viability was measured (n=6). (Click here to see method)</p>
 +
                <div class="collapseDiv">
 +
                    <label for="zhedie-toggle4">Method</label>
 +
                    <input type="checkbox" id="zhedie-toggle4" />
 +
                    <div id="zhedie4" class="text-success text-left">
 +
                        <b>Preparation of Cells for ATP assay</b><br>
 +
                        1. Grow HEK293T cells in a humidified 37 °C, 5% CO<sub>2</sub> tissue-culture incubator.<br>
 +
                        2. Count the cells using a hemocytometer. Seed in 96-well (1 × 10^4 per well) and grow
 +
                        overnight.<br>
 +
                        3. Transfect 0.5 μg DNA per well.<br>
 +
                        4. Equilibrate the plate and its contents at room temperature for approximately 30 minutes
 +
                        after 20 h.<br>
 +
                        5. Add a volume of CellTiter-Glo® Reagent equal to the volume of cell culture medium present in
 +
                        each well. (add 100 μl of reagent to 100 μl of medium containing cells for a 96-well plate).<br>
 +
                        6. Mix contents for 2 minutes on an orbital shaker to induce cell lysis.<br>
 +
                        7. Allow the plate to incubate at room temperature for 10 minutes to stabilize luminescent
 +
                        signal.<br>
 +
                        8. Record luminescence.<br><br>
 +
                    </div>
 +
                </div>
 
             </div>
 
             </div>
 +
            <div id="float04">
 +
                <div class="h1">Induce the expression of GSDMD-N275</div>
 +
                <div class="h2">Intracellular environment-dependent expression</div>
 +
                <p>P<sub>sifA</sub> is a intracellular environment-dependent promoter. SipD is required for bacterial
 +
                    internalization.
 +
                    Δ<i>sipD</i> mutant cannot enter host cells. Thus, we use this strain as a control. Microscopy suggested
 +
                    that only intracellular bacteria express eGFP which under the control of P<sub>sifA</sub> (Figure 8). </p>
 +
                <div style="width: 90%; margin: 0px auto">
 +
                    <img src="https://static.igem.org/mediawiki/2018/0/0b/T--HZAU-China--results8.png" width=100% alt="">
 +
                </div>
 +
                <p>Figure 8. Microscopy of hela GSDMD KO cells infected with the Δ<i>sipD</i> or Δ<i>sifA</i> mutant, respectively.
 +
                    These mutants contain a low copy number plasmid to express eGFP which was regulated by P<sub>sifA</sub></p>
 +
                <div class="collapseDiv">
 +
                    <label for="zhedie-toggle5">Method</label>
 +
                    <input type="checkbox" id="zhedie-toggle5" />
 +
                    <div id="zhedie5" class="text-success text-left">
 +
                        <b>Preparation of Cells for Infection</b><br>
 +
                        1. Grow Hela GSDMD KO cells in a humidified 37 °C, 5% CO<sub>2</sub> tissue-culture incubator.<br>
 +
                        2. Count the cells using a hemocytometer. Seed in 24-well (9× 10^4 per well) and grow
 +
                        overnight.<br>
 +
                        <b>Preparation of Bacteria</b> <br>
 +
                        1. Grow bacteria overnight 16 h in 2 mL LB in a 15-mL tube. Incubate at 37 °C in a shaking
 +
                        incubator (200 rpm).<br>
 +
                        2. Subculture bacteria by transferring 300 μL of the overnight culture into 5 mL of LB in a
 +
                        loosely capped 50-mL tube. Incubate at 37 °C in a shaking incubator (200 rpm) to late log
 +
                        phase.<br>
 +
                        3. Pellet 1 mL of the <i>Salmonella</i> subculture by centrifugation at 1000 g in a microfuge for 2
 +
                        min at room temperature.<br>
 +
                        4. Remove 900 μL of supernatant and gently resuspend the pellet in 900 μL PBS.<br>
 +
                        <b>Infection</b> <br>
 +
                        1. Aspirate media and rinse the monolayer twice with PBS.<br>
 +
                        2. Inoculate cells with bacteria (MOI = 100) by adding bacteria directly to the cell-culture
 +
                        supernatant.<br>
 +
                        3. Incubate for 3 h at 37 °C in 5% CO<sub>2</sub>.<br>
 +
                        4. Aspirate media and rinse the monolayer twice with PBS.<br>
 +
                        5. Add fresh GM containing 100 μg/mL gentamicin and incubate at 37 °C in 5% CO<sub>2</sub>.
 +
                        Observation is taken after 2 h.<br><br>
 +
                    </div>
 +
                </div>
 +
                <div class="h2">ATc-dependent expression</div>
 +
                <div class="h3">GSDMD-N275 can lyses bacteria</div>
 +
                <p>Expression of the N terminal of GSDMD fused with eGFP (eGFP-GSDMD-N275) in <i>Salmonella enterica</i>
 +
                    serovar Typhimurium str. SL1344 Δ<i>sifA</i> is under the control of P<sub>tet</sub>. The colony-forming unit (CFU)
 +
                    was measured for counting the number of viable bacteria (Figure 9). This result shows that
 +
                    eGFP-GSDMD-N275 exhibits cytotoxicity in bacteria.</p>
 +
                <div style="width: 40%; margin: 0px auto">
 +
                    <img src="https://static.igem.org/mediawiki/2018/f/fb/T--HZAU-China--basicPart3.jpg" width=100% alt="">
 +
                </div>
 +
                <p>Figure 9. CFU comparison between the SL1344 Δ<i>sifA</i> cells with eGFP-GSDMD-N275 plasmid and with the
 +
                    empty vector. In each group, ATc (15μg/ml) was added into medium when bacteria grown to logarithmic
 +
                    phase (OD = 0.6~0.8). Vector refers to bacteria containing a high copy number plasmid which only
 +
                    express TetR under the control of P<sub>tet</sub>. Bacterial colony-forming units (CFU) for vector
 +
                    and eGFP-GSDMD-N275 are shown in the logarithmic form (log10) (n=3).</p>
 +
                <div class="collapseDiv">
 +
                    <label for="zhedie-toggle6">Method</label>
 +
                    <input type="checkbox" id="zhedie-toggle6" />
 +
                    <div id="zhedie6" class="text-success text-left">
 +
                        1. Bacteria are cultured overnight in LB broth containing corresponding antibiotics, and
 +
                        dilute each 1 volume overnight cultures with 100 volume fresh LB containing antibiotics.
 +
                        Culture in 37℃ 200 rpm.<br>
 +
                        2. When OD reaching to 0.6-0.8, add anhydrotetracycline with final concentration of
 +
                        μg/ml to induce the expression of EGFP-GSDMD-N275.<br>
 +
                        3. Take 100 μl diluted culture to plate on LB agar plates containing appropriate concentration
 +
                        of antibody after 1.5 hours of induce.<br>
 +
                        Observation is taken overnight.<br><br>
 +
                    </div>
 +
                </div>
 +
 +
                <div class="h3">GSDMD-N275 from lytic bacteria induces host cell pyroptosis</div>
 +
                <p>Expression of the N-terminal of GSDMD fused with eGFP (eGFP-GSDMD-N275) is under the control of tet
 +
                    promoter in Δ<i>sifA</i> SL1344. Hela GSDMD KO cells were infected with Δ<i>sifA</i> SL1344. Inducer ATc
 +
                    (16μg/mL) were added 3h after infection. Microscopy shows that eGFP-GSDMD-N275 locates in cytoplasm
 +
                    after 5 min of induction and trigger pyroptosis after 30 min of induction (Figure 10). After 1.5 h
 +
                    of induction, Hela GSDMD KO cells undergo second necrosis caused by bacterial infection without
 +
                    inducer. Morphology of this process is similar to pyroptosis<sup>4</sup>. Thus, the population of ruptured
 +
                    cells was counted. There are 2-fold change between control group and induced group (Figure 11). So
 +
                    the pyroptosis of host cell in the induced group was triggered by eGFP-GSDMD-N275 not by bacterial
 +
                    infection.</p>
 +
                <div style="width: 90%; margin: 0px auto">
 +
                    <img src="https://static.igem.org/mediawiki/2018/b/b3/T--HZAU-China--basicPart4.png" width=100% alt="">
 +
                </div>
 +
                <p>Figure 10. Hela GSDMD KO cells were infected with Δ<i>sifA</i> SL1344 containing high copy number plasmids
 +
                    which express eGFP-GSDMD-N275 under the control of ATc. Photos were captured 5 min, 30min, 1.5h
 +
                    after induction, respectively.</p>
 +
                <div style="width: 40%; margin: 0px auto">
 +
                    <img src="https://static.igem.org/mediawiki/2018/2/22/T--HZAU-China--basicPart5.png" width=100% alt="">
 +
                </div>
 +
                <p>Figure 11. Numbers of pyroptotic cells before and after ATc induction. Ruptured cells in a field of
 +
                    view were counted. </p>
 +
                <div class="collapseDiv">
 +
                    <label for="zhedie-toggle7">Method</label>
 +
                    <input type="checkbox" id="zhedie-toggle7" />
 +
                    <div id="zhedie7" class="text-success text-left">
 +
                        <b>Preparation of Cells for Infection</b><br>
 +
                        1. Grow Hela GSDMD KO cells in a humidified 37 °C, 5% CO<sub>2</sub> tissue-culture incubator.<br>
 +
                        2. Count the cells using a hemocytometer. Seed in 24-well (5 × 10^4 per well) and grow
 +
                        overnight.<br>
 +
                        <b>Preparation of Bacteria</b> <br>
 +
                        1. Grow bacteria overnight 16 h in 2 mL LB in a 15-mL tube. Incubate at 37 °C in a shaking
 +
                        incubator (200 rpm).<br>
 +
                        2. Subculture bacteria by transferring 300 μL of the overnight culture into 5 mL of LB in a
 +
                        loosely capped 50-mL tube. Incubate at 37 °C in a shaking incubator (200 rpm) to late log
 +
                        phase.<br>
 +
                        3. Pellet 1 mL of the <i>Salmonella</i> subculture by centrifugation at 1000 g in a microfuge for 2
 +
                        min at room temperature.<br>
 +
                        4. Remove 900 μL of supernatant and gently resuspend the pellet in 900 μL PBS.<br>
 +
                        <b>Infection</b><br>
 +
                        1. Aspirate media and rinse the monolayer twice with PBS.<br>
 +
                        2. Inoculate cells with bacteria (MOI = 100) by adding bacteria directly to the cell-culture
 +
                        supernatant.<br>
 +
                        3. Incubate for 2 h at 37 °C in 5% CO<sub>2</sub>.<br>
 +
                        4. Aspirate media and wash.<br>
 +
                        5. Add fresh GM containing 100 μg/mL gentamicin and 16 μg/mL incubate at 37 °C in 5% CO<sub>2</sub>.<br>
 +
                        Observation is taken after 5 min, 30 min, 1.5 h.<br><br>
 +
                    </div>
 +
                </div>
 +
            </div>
 +
            <div id="float05">
 +
                <div class="h1">Reference</div>
 +
                <p>1 Dumont, A. et al. SKIP, the host target of the <i>Salmonella</i> virulence factor SifA, promotes
 +
                    kinesin-1-dependent vacuolar membrane exchanges. Traffic 11, 899-911,
 +
                    doi:10.1111/j.1600-0854.2010.01069.x (2010).
 +
                </p>
 +
                <p>2 Thurston, T. L. et al. Growth inhibition of cytosolic <i>Salmonella</i> by caspase-1 and caspase-11
 +
                    precedes host cell death. Nature communications 7, 13292, doi:10.1038/ncomms13292 (2016).</p>
 +
                <p>3 Hmelo, L. R. et al. Precision-engineering the Pseudomonas aeruginosa genome with two-step allelic
 +
                    exchange. Nat Protoc 10, 1820-1841, doi:10.1038/nprot.2015.115 (2015).</p>
 +
                <p>4 He, W. T. et al. Gasdermin D is an executor of pyroptosis and required for interleukin-1beta
 +
                    secretion. Cell research 25, 1285-1298, doi:10.1038/cr.2015.139 (2015).</p>
 +
            </div>
 +
 +
 +
 +
 +
 +
 +
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             <div class="daohangyi">
 
             <div class="daohangyi">
                    <span class="biaoti">Results</span>
+
                <span class="biaoti">Results</span>
                    <span class="xsjPic"><img src="https://static.igem.org/mediawiki/2018/8/8d/T--HZAU-China--xjt.svg" alt=""></span>
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                <span class="xsjPic"><img src="https://static.igem.org/mediawiki/2018/8/8d/T--HZAU-China--xjt.svg" alt=""></span>
 
             </div>
 
             </div>
 
             <div class="floatCtro">
 
             <div class="floatCtro">
                 <p class="daohanger">neirongyi</p>
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                 <p class="daohanger">Chassis</p>
                 <p class="daohanger">neironger</p>
+
                 <p class="daohanger">Targeting</p>
                 <p class="daohanger">neirongsan</p>
+
                 <p class="daohanger">Function of GSDMD</p>
 +
                <p class="daohanger">Induce the expression of GSDMD-N275</p>
 +
                <p class="daohanger">Reference</p>
 
                 <a>
 
                 <a>
 
                     <span>Back&nbsp;to&nbsp;Top</span>
 
                     <span>Back&nbsp;to&nbsp;Top</span>
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                 f3 = $('#float03').offset().top;
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<!-- {{HZAU-China}}
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<html>
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<div class="column full_size">
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<h1>Results</h1>
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<p>Here you can describe the results of your project and your future plans. </p>
 +
</div>
 +
 +
 +
<div class="column third_size" >
 +
 +
<h3>What should this page contain?</h3>
 +
<ul>
 +
<li> Clearly and objectively describe the results of your work.</li>
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<li> Future plans for the project. </li>
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<li> Considerations for replicating the experiments. </li>
 +
</ul>
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</div>
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 +
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<div class="column two_thirds_size" >
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<h3>Describe what your results mean </h3>
 +
<ul>
 +
<li> Interpretation of the results obtained during your project. Don't just show a plot/figure/graph/other, tell us what you think the data means. This is an important part of your project that the judges will look for. </li>
 +
<li> Show data, but remember all measurement and characterization data must be on part pages in the Registry. </li>
 +
<li> Consider including an analysis summary section to discuss what your results mean. Judges like to read what you think your data means, beyond all the data you have acquired during your project. </li>
 +
</ul>
 +
</div>
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 +
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<div class="clear extra_space"></div>
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<div class="column two_thirds_size" >
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<h3> Project Achievements </h3>
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<p>You can also include a list of bullet points (and links) of the successes and failures you have had over your summer. It is a quick reference page for the judges to see what you achieved during your summer.</p>
 +
 +
<ul>
 +
<li>A list of linked bullet points of the successful results during your project</li>
 +
<li>A list of linked bullet points of the unsuccessful results during your project. This is about being scientifically honest. If you worked on an area for a long time with no success, tell us so we know where you put your effort.</li>
 +
</ul>
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</div>
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<div class="column third_size" >
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<div class="highlight decoration_A_full">
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<h3>Inspiration</h3>
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<p>See how other teams presented their results.</p>
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<ul>
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<li><a href="https://2014.igem.org/Team:TU_Darmstadt/Results/Pathway">2014 TU Darmstadt </a></li>
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<li><a href="https://2014.igem.org/Team:Imperial/Results">2014 Imperial </a></li>
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<li><a href="https://2014.igem.org/Team:Paris_Bettencourt/Results">2014 Paris Bettencourt </a></li>
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</ul>
 +
</div>
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</div>
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 +
 +
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 +
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</html> -->

Revision as of 19:38, 16 October 2018

Chassis
sifA knock out

SifA maintains the integrity of Salmonella-containing vacuole (SCV) where Salmonella survive and replicate1. The existence of SCV limits the releasing of GSDMD-N275 into cytoplasm. In addition, the growth of inhibition of ΔsifA mutant in macrophage is remarkable2. Thus, we knocked out the sifA gene in order to prevent the stability of SCV and reduce the virulence of Salmonella.

ΔsifA mutant was constructed by using gene editing system based on two-step allelic exchange3.

PCR verification indicated that chromosomal gene sifA was knocked out (Figure 1). Primers named DSIFA F and DSIFA R were used in this PCR (Figure 2).

Figure 1. PCR verification of sifA gene knock out. Lane 1 refers to mutant candidate. Lane 2 refers to WT Salmonella enterica var. Typhimurium SL1344 as a control.

Figure 2. DSIFA F and DSIFA R are the primers in the ORF of sifA. This pair of primers can extend a 436bp product in WT.

Safety

SifA is essential for maintaining vacuolar membrane stability. Cytosolic bacteria can be generated by the function loss of Salmonella-containing vacuole (SCV). This population of bacteria was easily recognized and cleaned up by macrophage. Hence, ΔsifA mutant decrease the toxicity to the host. Microscopy demonstrated that ΔsifA mutant was defective for replication in macrophage (Figure 3).

Figure 3. Microscopy of immortalized bone-marrow-derived macrophages (iBMDM) infected with the ΔsifA mutant and WT Salmonella, respectively. These strains contain a high copy number of plasmids to express RFP constitutively.

Preparation of Cells for Infection
1. Grow iBMDMs in a humidified 37 °C, 5% CO2 tissue-culture incubator.
2. Count the cells using a hemocytometer. Seed in 24-well (5 × 10^4 per well) and grow overnight .
Preparation of Bacteria 1. Grow bacteria overnight 16 h in 2 mL LB in a 15-mL tube. Incubate at 37 °C in a shaking incubator (200 rpm).
2. Subculture bacteria by transferring 300 μL of the overnight culture into 5 mL of LB in a loosely capped 50-mL tube. Incubate at 37 °C in a shaking incubator (200 rpm) to late log phase.
3. Pellet 1 mL of the Salmonella subculture by centrifugation at 1000 g in a microfuge for 2 min at room temperature.
4. Remove 900 μL of supernatant and gently resuspend the pellet in 900 μL PBS.
Infection 1. Aspirate media and rinse the monolayer twice with PBS.
2. Inoculate cells with bacteria (MOI = 20) by adding bacteria directly to the cell-culture supernatant. Centrifugation at 110 g for 5 min at room temperature.
3. Incubate for 25 min at 37 °C in 5% CO2.
4. Aspirate media and rinse the monolayer twice with PBS, to remove extracellular bacteria.
5. Add fresh GM containing 100 μg/mL gentamicin and incubate for 2 h at 37 °C in 5% CO2.
6. Replace GM with fresh GM containing 20 μg/mL gentamicin for remainder of experiment.
Observation is taken after 11 h.

Targeting

RGD motif can specifically bind to alpha V beta 3 (αVβ3) a well-known biomarker on the surface of tumor cells. We express RGD motif fused with OmpA to surface display it on the outer membrane of bacteria. Microscopy shows that bacteria expressed Lpp-OmpA-RGD induced by 0.1 mM IPTG can bind to αVβ3-positive MDA-MB-231 cell line. The location of bacteria is pointed by red arrow (Figure 4). But cannot bind to αVβ3-negative MCF7 cell line (Figure 5). These results demonstrated that bacteria gain the function of tumor targeting though display RGD motif.

Figure 4. Microscopy of αVβ3-positive MDA-MB-231 cell line were incubated with E. coli which constructive expressed RFP and inductive expressed RGD motif under the control of lac promoter.

Figure 5. Microscopy of αVβ3-negative MCF7 cell line were incubated with E. coli which constructive expressed RFP and inductive expressed RGD motif under the control of lac promoter.

Preparation of Cells
1. Grow MDA-MB-231 and MCF7 in a humidified 37 °C, 5% CO2 tissue-culture incubator.
2. Count the cells using a hemocytometer. Seed in 24-well (1.5× 10^5 per well) and grow overnight.
Preparation of Bacteria 1. Grow bacteria overnight 14 h in 2 mL LB in a 15-mL tube. Incubate at 37 °C in a shaking incubator (200 rpm).
2. Subculture bacteria by transferring 300 μL of the overnight culture into 5 mL of LB containing 0.1 mM IPTG in a loosely capped 50-mL tube. Incubate at 37 °C in a shaking incubator (200 rpm) to early stationary phase.
3. Pellet 1 mL of the bacteria subculture by centrifugation at 1000 g in a microfuge for 2 min at room temperature.
4. Remove 900 μL of supernatant and gently resuspend the pellet in 900 μL PBS.
Infection 1. Aspirate media and rinse the monolayer twice with PBS.
2. Inoculate cells with bacteria (MOI = 100) by adding bacteria directly to the cell-culture supernatant.
3. Incubate for 1.5 h at 37 °C in 5% CO2.
4. Aspirate media and rinse the monolayer three times with PBS.
Observation is taken immediately.

Function of GSDMD
The N-terminal of GSDMD performs the function of cell pyroptosis

We fused eGFP with GSDMD-N275 and GSDMD FL (full length), respectively. Then the corresponding plasmids were transfected into Hela GSDMD KO cell. Cell microscopy showed that the cells transfected with GSDMD-N275 underwent pyroptosis while the cells with GSDMD FL did not (Figure 6). We also tested the cell viability though an ATP assay (CellTiter-Glo® Luminescent Cell Viability Assay) and demonstrated that GSDMD-N275 and mutants of GSDMD FL have different ability to induce pyroptosis (Figure 7).

Figure 6. Microscopy of the Hela GSDMD KO cells transfected with pCS2-eGFP-GSDMD FL and pCS2-eGFP-GSDMD-N275, respectively. Pyroptotic cells are pointed by red arrow.

Preparation of Cells for transfection
1. Grow Hela GSDMD KO cells in a humidified 37 °C, 5% CO2 tissue-culture incubator.
2. Count the cells using a hemocytometer. Seed in 24-well (5 × 10^4 per well) and grow.
Transfection
1. Dilute 0.5 μg DNA into 50 μl jetPRIME® buffer (supplied). Mix by vortexing.
2. Add 1 μl jetPRIME®, vortex for 10 s, spin down briefly.
3. Incubate for 10 min at RT.
4. Add 50μl of transfection mix per well drop wise onto the cells in serum containing medium, and distribute evenly.
5. Gently rock the plates back and forth and from side to side.
6. If needed, replace transfection medium after 4 h by cell growth medium and return the plates to the incubator.
Observation is taken after 1.5 h.

Figure 7. Cell viability of the 293T cells transfected with pCS2-Flag-GSDMD FL, pCS2-Flag-GSDMD-N275, pCS2-Flag-GSDMD L290D, pCS2-Flag-GSDMD Y373D, pCS2-Flag-GSDMD A377D, respectively. Asterisks indicate the statistically significant differences. ATP-based cell viability was measured (n=6). (Click here to see method)

Preparation of Cells for ATP assay
1. Grow HEK293T cells in a humidified 37 °C, 5% CO2 tissue-culture incubator.
2. Count the cells using a hemocytometer. Seed in 96-well (1 × 10^4 per well) and grow overnight.
3. Transfect 0.5 μg DNA per well.
4. Equilibrate the plate and its contents at room temperature for approximately 30 minutes after 20 h.
5. Add a volume of CellTiter-Glo® Reagent equal to the volume of cell culture medium present in each well. (add 100 μl of reagent to 100 μl of medium containing cells for a 96-well plate).
6. Mix contents for 2 minutes on an orbital shaker to induce cell lysis.
7. Allow the plate to incubate at room temperature for 10 minutes to stabilize luminescent signal.
8. Record luminescence.

Induce the expression of GSDMD-N275
Intracellular environment-dependent expression

PsifA is a intracellular environment-dependent promoter. SipD is required for bacterial internalization. ΔsipD mutant cannot enter host cells. Thus, we use this strain as a control. Microscopy suggested that only intracellular bacteria express eGFP which under the control of PsifA (Figure 8).

Figure 8. Microscopy of hela GSDMD KO cells infected with the ΔsipD or ΔsifA mutant, respectively. These mutants contain a low copy number plasmid to express eGFP which was regulated by PsifA

Preparation of Cells for Infection
1. Grow Hela GSDMD KO cells in a humidified 37 °C, 5% CO2 tissue-culture incubator.
2. Count the cells using a hemocytometer. Seed in 24-well (9× 10^4 per well) and grow overnight.
Preparation of Bacteria
1. Grow bacteria overnight 16 h in 2 mL LB in a 15-mL tube. Incubate at 37 °C in a shaking incubator (200 rpm).
2. Subculture bacteria by transferring 300 μL of the overnight culture into 5 mL of LB in a loosely capped 50-mL tube. Incubate at 37 °C in a shaking incubator (200 rpm) to late log phase.
3. Pellet 1 mL of the Salmonella subculture by centrifugation at 1000 g in a microfuge for 2 min at room temperature.
4. Remove 900 μL of supernatant and gently resuspend the pellet in 900 μL PBS.
Infection
1. Aspirate media and rinse the monolayer twice with PBS.
2. Inoculate cells with bacteria (MOI = 100) by adding bacteria directly to the cell-culture supernatant.
3. Incubate for 3 h at 37 °C in 5% CO2.
4. Aspirate media and rinse the monolayer twice with PBS.
5. Add fresh GM containing 100 μg/mL gentamicin and incubate at 37 °C in 5% CO2. Observation is taken after 2 h.

ATc-dependent expression
GSDMD-N275 can lyses bacteria

Expression of the N terminal of GSDMD fused with eGFP (eGFP-GSDMD-N275) in Salmonella enterica serovar Typhimurium str. SL1344 ΔsifA is under the control of Ptet. The colony-forming unit (CFU) was measured for counting the number of viable bacteria (Figure 9). This result shows that eGFP-GSDMD-N275 exhibits cytotoxicity in bacteria.

Figure 9. CFU comparison between the SL1344 ΔsifA cells with eGFP-GSDMD-N275 plasmid and with the empty vector. In each group, ATc (15μg/ml) was added into medium when bacteria grown to logarithmic phase (OD = 0.6~0.8). Vector refers to bacteria containing a high copy number plasmid which only express TetR under the control of Ptet. Bacterial colony-forming units (CFU) for vector and eGFP-GSDMD-N275 are shown in the logarithmic form (log10) (n=3).

1. Bacteria are cultured overnight in LB broth containing corresponding antibiotics, and dilute each 1 volume overnight cultures with 100 volume fresh LB containing antibiotics. Culture in 37℃ 200 rpm.
2. When OD reaching to 0.6-0.8, add anhydrotetracycline with final concentration of μg/ml to induce the expression of EGFP-GSDMD-N275.
3. Take 100 μl diluted culture to plate on LB agar plates containing appropriate concentration of antibody after 1.5 hours of induce.
Observation is taken overnight.

GSDMD-N275 from lytic bacteria induces host cell pyroptosis

Expression of the N-terminal of GSDMD fused with eGFP (eGFP-GSDMD-N275) is under the control of tet promoter in ΔsifA SL1344. Hela GSDMD KO cells were infected with ΔsifA SL1344. Inducer ATc (16μg/mL) were added 3h after infection. Microscopy shows that eGFP-GSDMD-N275 locates in cytoplasm after 5 min of induction and trigger pyroptosis after 30 min of induction (Figure 10). After 1.5 h of induction, Hela GSDMD KO cells undergo second necrosis caused by bacterial infection without inducer. Morphology of this process is similar to pyroptosis4. Thus, the population of ruptured cells was counted. There are 2-fold change between control group and induced group (Figure 11). So the pyroptosis of host cell in the induced group was triggered by eGFP-GSDMD-N275 not by bacterial infection.

Figure 10. Hela GSDMD KO cells were infected with ΔsifA SL1344 containing high copy number plasmids which express eGFP-GSDMD-N275 under the control of ATc. Photos were captured 5 min, 30min, 1.5h after induction, respectively.

Figure 11. Numbers of pyroptotic cells before and after ATc induction. Ruptured cells in a field of view were counted.

Preparation of Cells for Infection
1. Grow Hela GSDMD KO cells in a humidified 37 °C, 5% CO2 tissue-culture incubator.
2. Count the cells using a hemocytometer. Seed in 24-well (5 × 10^4 per well) and grow overnight.
Preparation of Bacteria
1. Grow bacteria overnight 16 h in 2 mL LB in a 15-mL tube. Incubate at 37 °C in a shaking incubator (200 rpm).
2. Subculture bacteria by transferring 300 μL of the overnight culture into 5 mL of LB in a loosely capped 50-mL tube. Incubate at 37 °C in a shaking incubator (200 rpm) to late log phase.
3. Pellet 1 mL of the Salmonella subculture by centrifugation at 1000 g in a microfuge for 2 min at room temperature.
4. Remove 900 μL of supernatant and gently resuspend the pellet in 900 μL PBS.
Infection
1. Aspirate media and rinse the monolayer twice with PBS.
2. Inoculate cells with bacteria (MOI = 100) by adding bacteria directly to the cell-culture supernatant.
3. Incubate for 2 h at 37 °C in 5% CO2.
4. Aspirate media and wash.
5. Add fresh GM containing 100 μg/mL gentamicin and 16 μg/mL incubate at 37 °C in 5% CO2.
Observation is taken after 5 min, 30 min, 1.5 h.

Reference

1 Dumont, A. et al. SKIP, the host target of the Salmonella virulence factor SifA, promotes kinesin-1-dependent vacuolar membrane exchanges. Traffic 11, 899-911, doi:10.1111/j.1600-0854.2010.01069.x (2010).

2 Thurston, T. L. et al. Growth inhibition of cytosolic Salmonella by caspase-1 and caspase-11 precedes host cell death. Nature communications 7, 13292, doi:10.1038/ncomms13292 (2016).

3 Hmelo, L. R. et al. Precision-engineering the Pseudomonas aeruginosa genome with two-step allelic exchange. Nat Protoc 10, 1820-1841, doi:10.1038/nprot.2015.115 (2015).

4 He, W. T. et al. Gasdermin D is an executor of pyroptosis and required for interleukin-1beta secretion. Cell research 25, 1285-1298, doi:10.1038/cr.2015.139 (2015).

Description Design
Results

Chassis

Targeting

Function of GSDMD

Induce the expression of GSDMD-N275

Reference

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