Medical Xpress (09.26.12)
Aids Weekly Plus
Researchers led by Dr. Joanna Kirman of the Department of Microbiology, University of Otago, New Zealand, have tested an oral vaccination formula that can create a stronger and longer-lasting immune response in mice compared to that from the current injected TB vaccine. The bacteria in an oral vaccine have to be live for the vaccine to work. To overcome the problem of live bacteria not surviving the journey through the stomach, Dr. Frank Alwell and colleagues from Immune Solutions Ltd, based at the university, created a lipid formulation called LiporaleTM that coats the BCG bacteria.
The researchers compared the immune response in the spleen and lungs of mice vaccinated with the new vaccine, LiporaleTM-BCG, to the immune response generated by the traditional injected vaccination. According to Dr. Kirman, the LiporaleTM-BCG vaccine induced a long-lived immune response, as the subjects had increased numbers of TB-specific T cells in their lungs and spleen up to 30 weeks after vaccination. Results show that the orally delivered LiporaleTM-BCG vaccine induces a long-lived multi-functional immune response and can be a practical and effective method of delivering new BCG-based TB vaccines. Also, it targets the mucosal immune system of the gut and respiratory tract where the immune response is regulated differently from that triggered by injected vaccines.
The researchers are hoping that the vaccine will bring in more funding to continue the work on immune response and perform safety tests. The nonprofit organization AERAS, has undertaken to conduct further tests on the vaccine.
The study titled, “Oral Vaccination with Lipid-Formulated BCG Induces a Long-Lived, Multifunctional CD4+ T Cell Memory Immune Response,” was published in the journal PLOS ONE (7(9): e45888. doi:10.1371/journal.pone.0045888).