B cell

A white blood cell that comes from bone marrow. As part of the immune system, B cells make antibodies and help fight infections. Also called B lymphocyte.

An important class of lymphocytes that mature in bone marrow (in mammals) and the Bursa of Fabricius (in birds) and produce antibodies. Largely responsible for the antibody-mediated or humoral immune response, giving rise to the antibody-producing plasma cells and some other cells of the immune system. Synonym: B lymphocyte.