What is C.Difficile?

A meta analysis predicted 6.3 $ billion dollars spent annually on attributable costs ofClostridium difficile infectionsMore than 250,000 people require hospitalization of this pathogen in the U.S alone.

Clostridium difficile is a major cause of healthcare associated diarrhea. Withincreasing outbreaks of hypervirulent strains worldwide due to the developmentof antibiotic resistance. Symptoms can range from dehydration and fever to toxicmegacolon and sepsis. Patients who have undergone treatment with broadspectrum antibiotics or are immunocompromised are particularly susceptible tothis pathogen because their gut flora is likely to be in a dysbiotic state.

Meaning fewer commensal bacteria are available to fend off pathogens or takeup space in the gastrointestinal tract. Increasing the likelihood of a Clostridiumdifficile infection. As well as certain strains being able to resist environmentalstresses such as heat, hydrogen peroxide and even ethanol. Makingcontamination much harder to control even with sterilizing techniques.

Currently treatment largely consists of using antibiotics which has the detrimentaleffect of further damaging commensal bacteria in the gut. With 1 in 5 patientsexperiencing recurrence of infection, this method of remedification is not optimaland is highly prone to increase the likelihood of bacteria developing antibioticresistance. Unsatisfied with the current efficacy of this treatment we propose anew therapy.

Bacteriophage (phage) therapy: An alternative treatment to using antibiotics thatis becoming increasingly recognized in western medicine, primarily due to drasticincrease of antibiotic resistance seen over the past few years.

Phage: Small vectors of genetic material encased in protein shells, and a tail that allowsthem to bind and transfer information between organisms. (Picture of a phage)

Phage propagate primarily via two different mechanisms:

Lytic

Lysogenic

A lot of phage therapy today focuses on using phages lytic in nature to eradicatebacterial populations. However our phage utilizes lysogeny to suppress toxin productionand leave the clostridium difficile in the gut as a commensal bacteria.
The rational fear for this is:

Able to fend of potentially more harmful opportunistic pathogens

Take up space in the gut

By not rapidly lysing whole populations of bacteria, the release of relatively highconcentrations of potentially harmful enzymes and other intracellular componentsis avoided which might further exacerbate the dysbiotic environment in thegastrointestinal tract.

How are we doing this: We are synthetically engineering a temperate phage to express geneticconstructs that we will use against Clostridium difficile to stop them from synthesizing toxins.The first genetic construct is antisense RNA, and the second is dead Cas9