Emerging pandemics like COVID-19 need instant effective vaccines. Currently, the most successful vaccines are equipped in liposome or adenovirus vectors, which are delivered intravenously into human body. Antigen proteins produced through human-self cells trigger immune responses. For immediate use, the protein target from a less-known pathogen to be determined may be physiologically toxic to human cells.
Commensal bacteria are normal flora living in humans. What if the antigen gene being transferred into them? Could the antigen protein be produced and be effective to induce immune responses?
In our project, we engineered a T7 bacteriophage with a model antigen (ovalbumin) gene. The isolated intestinal E. coli were tested susceptible to the phages and can produce the antigen proteins. We created a model of phage vector - commensal bacteria - antigen production. Based on clinical phage therapy procedure, we are planning to conduct animal studies to examine the effectiveness for phage vaccine.