Vaccines, Adjuvants and Mucosal Immunity

While these "antibody-based" vaccine technologies have proven effective against a number of infectious diseases like diphtheria, measles and mumps, they may be ineffective when used to combat other infections, including tuberculosis, herpes, Zika virus and rapidly mutating viruses such as SARS-CoV-2 and influenza.

Trudeau’s first Director, Dr. George B. Mackaness, is widely credited with the discovery that another component of the immune system - the cellular immune response - provides an alternative correlate of protection by which vaccines can combat infectious disease. To help boost these immune responses, adjuvants are used as vaccine additives to help activate innate immunity to drive strong, long-lived anti-pathogen cellular immunity that persists into the memory phase. Vaccine strategies that use adjuvants to fine-tune the T cell response, coupled with vaccine administration at mucosal sites such as the respiratory and reproductive tract can induce populations of T cells, ready to combat infections at sites of pathogen entry. Thus, vaccines that can stimulate both humoral (antibody) mediated and cellular (T cell) mediated immunity offer tremendous promise.

A number of Trudeau Institute scientists are striving to fulfill that promise. We have developed vaccine models of influenza, tuberculosis, Zika virus and SARS-CoV-2, using different vaccine adjuvants and administration sites in which both humoral and cellular immunity confer mice with durable protection. Using these models, we are studying the mechanisms that regulate cellular immune responses and determining which adjuvants may elicit potent, protective and durable cellular immunity at mucosal sites.