Team:UC Davis/AchalaTestPage
Mammalian Cell Biosensor For Environmental Toxicology
Our project aims to develop mammalian-based biosensors for use in the context of environmental toxicology. Specifically, out biosensors have been designed to co-opt the mammalian cell’s intrinsic stress response pathways and use these to trigger the production of a fluorescent reporter. We hypothesize that a device reporting on the activation of cell stress pathways will provide more physiologically and health relevant information about the potential toxins present in an environment than bioassays which seek to simply measure compound presence and/or abundance. That is, our bioassay asks not whether a compound is there, but rather whether compounds exists that may pose a health hazard. We leave the identification of the specific hazards to more sensitive and quantitative techniques.
Our biosensors use mammalian-derived promoters of genes known to be activated in response to stress-inducing environmental pollutants. These promoters are coupled to a reporter gene (eGFP) and used in in vitro assays to report on the presence of compounds that elicit cell stress.
Our biosensors use mammalian-derived promoters of genes known to be activated in response to stress-inducing environmental pollutants. These promoters are coupled to a reporter gene (eGFP) and used in in vitro assays to report on the presence of compounds that elicit cell stress.
Inspiration
Earlier this year, we were really fortunate to visit an indigenous tribe of people who live in Klamath, Ca - a beautiful city in the coastal regions of northern California.
The tribe have reported unusually elevated rates of cancer and miscarriage incidence, and have indicated they have reason to suspect that the cause may be tied to environmental pollution on their tribal land from local agricultural and forestry corporations. Researchers from UC Davis have been collaborating with the tribe’s scientists and governing council to gather data pertaining to environmental and human health.
The tribe have reported unusually elevated rates of cancer and miscarriage incidence, and have indicated they have reason to suspect that the cause may be tied to environmental pollution on their tribal land from local agricultural and forestry corporations. Researchers from UC Davis have been collaborating with the tribe’s scientists and governing council to gather data pertaining to environmental and human health.
How does it work?
We reasoned that health impacts from exposure to toxins, particularly low level exposure, elicits a very complex cellular response that involves the change in activity and regulation of many genes simultaneously;
these are very complex pathways that we still have a lot to learn about, but we imagine that they are similar to intricate built in sensors of health that are very hard to engineer ourselves. So we took advantage of that.
the basic premise of our project is that we are taking advantage of what mammalian cells offer as a chassis and then we engineered them to tell us the stress they are experiencing in a way that we can quantify.
The specific promoters we have identified for our project control the expression of the following genes: Metallothionein 1, Metallothionein 2, Fibroblast growth factor(FGF21), and the Growth arrest and DNA Damage(GADD45a and GADD153). The representative environmental toxins that we plan to stimulate our engineered cells with include: 2,4-Dichlorophenoxyacetic acid, Warfarin, Metam Sodium, and Copper Sulfate. We are also using Hydrogen Peroxide as a positive control.
The specific promoters we have identified for our project control the expression of the following genes: Metallothionein 1, Metallothionein 2, Fibroblast growth factor(FGF21), and the Growth arrest and DNA Damage(GADD45a and GADD153). The representative environmental toxins that we plan to stimulate our engineered cells with include: 2,4-Dichlorophenoxyacetic acid, Warfarin, Metam Sodium, and Copper Sulfate. We are also using Hydrogen Peroxide as a positive control.
Future
A possible extension of our research would be to determine the effect of multiple chemicals of concern(COCs) on the physiological health of mammalian cells. This would be of value in assessing and creating sane standards for pollution, as organisms in the natural environment are exposed to a variety of COCs at once, which may not have been previously screened in conjunction with each other. A possible finding from this might be that COC “A,” at a concentration below what is currently considered to be harmful, in the presence of COC “B,” also at a concentration below what is currently considered to be harmful, interact together to trigger a response associated with stress in mammalian cells.