What is the primary function of Memory B cells?

Memory B cells play a crucial role in the immune system's ability to recognize and respond to pathogens that the body has previously encountered. After an initial exposure to an antigen, B cells that are activated can differentiate into plasma cells, which produce antibodies to help neutralize the pathogen. A subset of these activated B cells, however, becomes memory B cells.

The primary function of memory B cells is to facilitate a rapid and effective response upon subsequent exposures to the same antigen. This is achieved because memory B cells persist in the body long after the initial infection has been cleared, remaining in a quiescent state. When the same antigen is detected again, these memory B cells can quickly proliferate and differentiate into plasma cells, producing large quantities of antibodies specifically targeted to that antigen. This enables a faster and more intense immune response compared to the first encounter with the pathogen, providing long-lasting immunity.

By ensuring a quick and robust secondary immune response, memory B cells are essential for long-term protection against specific infections, which is why vaccinations can be so effective in preventing diseases.