Protein that enhances vaccine efficacy identified

Researchers have discovered a protein that could help make vaccinations more effective and also provide protection from other diseases such as cancer.

The researchers purified a protein found on the exterior of bacteria (neisseria meningidis) and used it as an accessory to provide a better vaccination response. 

Typically, vaccines can either increase the amount of antibody production or they can stimulate cells (called cytotoxic T cells) to directly kill the offending agent. 

The protein, called PorB, is unique in that it can do both, the researchers said. 

The study, published online in the journal Scientific Reports, may lead to greater understanding of how vaccine enhancers work and can best be used.

"This study has wide implications as it could not only be used to help the body identify and fight off bacterial infections, but it could also potentially help the body use its own machinery to fight off other diseases like cancer, HIV, and influenza before they have a chance to establish within the body," explained corresponding author lee Wetzler, Professor of Medicine and Microbiology at Boston University School of Medicine (BUSM) in the US.

In this study, the researchers used two experimental models. The first model was given a vaccination with antigen and mixed PorB, while the second model was given the antigen alone. 

The model that received the PorB had an increase in the response to the vaccine antigen, evidenced by an increased number of activated cells in the lymph nodes and a gain in the production of cytotoxic T cells, as compared to the vaccination with the antigen alone.

"Our study deepens the general understanding of how vaccine adjuvants modulate immune responses," Wetzler said.

"The antigen formulation with PorB triggers a sequence of cellular events at the periphery and in lymphoid tissue that are critical for the establishment of protection to a broad array of infectious diseases, and maybe for other diseases like cancer," Wetzler added.