Which immune response is primarily carried out by B cells?

B cells play a crucial role in the immune system, particularly in humoral immunity. This aspect of the immune response involves the production of antibodies which are proteins that can specifically recognize and bind to pathogens such as bacteria and viruses. When B cells encounter an antigen, they can differentiate into plasma cells that secrete large amounts of antibodies into the bloodstream. These antibodies then neutralize toxins, block the ability of pathogens to infect cells, and mark them for destruction by other immune cells.

Humoral immunity is vital for controlling extracellular pathogens and is distinct from cell-mediated immunity, which is primarily executed by T cells. The inflammatory response and phagocytosis do involve various immune cells, including those that B cells may activate or work alongside, but they are not the primary functions of B cells. The specific role of B cells in producing antibodies is what characterizes humoral immunity and forms the basis of adaptive immune response against pathogens.