Team:Penn/HumanPracticesOverview

Many previous iGEM teams have tried to implement a bacterial therapeutic as part of their project. Outside of iGEM, there has been a steady interest in engineering bacteria to become therapeutic vectors as well. However, the question that guided our human practices project was essentially:

Why aren't bacterial therapeutics transitioning into clinical practice or even clinical trials?

While there are certainly many barriers to bacterial therapeutics such as time and money, we hypothesize that iGEM teams, as a result of their unique positions as research and educational institutions, are positioned to address two major barriers to the adoption of bacterial therapeutics: biological barriers and perception barriers.

From a technological standpoint, there is a great deal of work that remains to be done before a bacterial therapeutic can enter the drug development pipeline. While many iGEM teams, including us, have helped set the groundwork for bacterial therapeutics, there are still some biological barriers to a bacterial therapeutic. We identified the immunogenicity of laboratory strains of E. coli. as a major biological barrier. We then investigated methods to decrease the immunogenicity of E. coli., eventually choosing to port modules of our target drug delivery system into a non-immunogenic strain of E. coli., Nissle 1917.

Furthermore, in an effort to speed progress and information sharing between iGEM teams, government research organizations, and private research groups, we have proposed a system known as VerifiGEM that would allow for the quality control of BioBricks to be distributed across the entire iGEM community. Should our system be implemented, the overall quality and reliability of BioBricks will be improved greatly, at very little cost to individual iGEM teams.

However, the removal of biological barriers to bacterial therapeutics alone is not sufficient to enable bacterial therapeutics to move into the drug development pipeline. Through the course of recent history, many high profile technologies, such as gene therapy or nanotechnology have been met with public skepticism and even fear, as the technologies failed to deliver on earlier promises. This prompted a constriction of available funding and subsequently impeded progress in those fields, an outcome that nanotechnology in particular is only just beginning to recover from.

We propose a model, adapted from Gartner Inc, which proposes that the disconnect between the expectations of the public and the realities of scientific research produces an initial "peak of inflated expectations" (and funding), that rapidly disappears as promised advances are delayed or do not work as planned (Figure 1). We believe that this "trough of disillusionment" is the cause of restrictions in funding and a general stall of scientific progress in a given field. We propose that the peak can be smoothed out, reducing the size of peak, but more importantly, eliminating the trough of disillusionment (Figure 2).

Upon conception of this project, we realized that although hundreds of academic research projects and iGEM projects have been conducted in the realm of Health and Medicine, almost no engineered bacterial therapeutics have been brought to the clinic. We analyzed the hurdles and road ahead for bacterial synthetic biology-enabled therapeutics, compiling a thorough report with specific actions which iGEM teams in Health/Medicine can take to make their therapies more clinically tractable. This project directly informed our wet lab work, causing us to port our therapeutic system into a non-pathogenic, probiotic bacterial strain which is already used in human therapies today.

We hope our targeted therapeutic platform will allow other scientists and iGEM teams to target any cells they choose. In the near term, we are planning to test our cancer cell targeting/killing bacterial system in a mouse model and make a real impact on cancer research and therapy.