HBV Vaccination of Healthy Volunteers to Evaluate the Composition of Germinal Centers

The Effects of HBV Vaccine on Memory B Cells

Antibodies are the primary mediators of the protection against infection provided by
 vaccination. Antibodies become most powerful after the B cells that produce them undergo an
 evolutionary process called affinity maturation, in which antibodies increase their ability
 to bind to their targets, and thus neutralize pathogens. Affinity maturation occurs in
 structures within secondary lymphoid organs (for example lymph nodes or tonsils) known as
 germinal centers. Germinal centers are well known to be triggered by the first dose of
 vaccines, generating affinity matured plasma cells (B cells that secrete antibody into serum)
 and memory B cells, which can be converted into plasma cells by booster doses of vaccine.
 However, it is not fully understood the extent to which memory B cells can return to germinal
 centers again upon vaccine boosting. Such return would be very important to allow B cells,
 for example, to adapt to emerging variants of viruses such as influenza or SARS-CoV-2. This
 study will involve acquiring samples of B cells from germinal centers that form in response
 to vaccination with the highly effective hepatitis B vaccine. These cells will be analyzed to
 determine what fraction of them are memory B cells that returned to germinal centers upon
 boosting, information that is key to knowledge of how vaccine boosters work. Understanding
 the rules that govern how and when memory B cells choose to return to germinal centers in
 an effective vaccine such hepatitis B could help efforts to develop effective vaccination
 against more challenging, rapidly mutating viruses, such as influenza, HIV, and hepatitis C.