Engineering probiotics for therapeutic applications: recent examples and translational outlook

Engineered probiotics are the next generation of live biotherapeutics that have been genetically modified to target specific diseases. With the advancements in synthetic biology, the engineering of probiotics has become increasingly sophisticated which has led to the development of therapies for treating cancer, infection, metabolic disorders and inflammation, as well as for diagnosing and preventing them. Herein, we review some of the recent examples of probiotics which have been engineered to target such diseases. Although there are numerous examples of engineered probiotics showing efficacy in animal models, there are no approved products on the market with very few in clinical trials. Therefore, we also discuss a set of features that may be incorporated into engineered probiotics to aid in clinical translation and ultimately, realizing the potential of these biotherapeutics.