粘膜IgA抗体強化のための新規ワクチンアジュバントの免疫評価

抄録

In the mucosa, IgA antibodies are secreted as multimeric antibodies, which play important roles in normal flora control as well as in infection control. In contrast to IgG antibodies, which are predominantly specific for a single antigen, these mucosal IgA antibodies are known to be broadly antigen-specific, allowing a single type of antibody to respond to multiple antigens.

For SARS-CoV2, it has been shown that multimeric IgM and IgA antibodies can cope with more variants than IgG antibodies. Thus, the development of an effective mucosal vaccine adjuvant that induces mucosal polymeric IgA antibodies provides strong mucosal protection against bacterial and viral infections. This is very different from the conventional vaccine that stimulates the increase of antibody in the serum by intramuscular injection and targets the pathogen after invasion into the body. We believe that it is important for B cells activated by antigens to efficiently migrate to germinal centers in order to induce high-affinity antibodies on mucosal surfaces. We have therefore found a marker for pre-germinal center B cells and are conducting research on substances that induce this marker as novel mucosal vaccine adjuvants. We discuss the evaluation of mucosal immunity of vaccine adjuvants based on intestinal germinal center B cell responses.