Medical Term Definition

B Lymphocyte

A type of lymphocyte that recognizes specific targets and can produce antibodies by differentiating into plasma cells.

B lymphocytes, commonly called B cells, are part of the adaptive immune system. When appropriately activated, they can differentiate into plasma cells that produce antibodies and into memory B cells that help the immune system respond more rapidly to a future encounter with the same target.

B cells contribute to protection against infections and can also play roles in immune regulation and, in some diseases, inappropriate immune responses.

QUICK FACT

The “B” in B lymphocyte originally referred to the bursa of Fabricius in birds, where B cells were first identified as a distinct lymphocyte population. In humans, B-cell development occurs primarily in the bone marrow.

COMMONLY CONFUSED WITH

T lymphocyte: B lymphocytes are especially associated with antibody-mediated immune responses, while T lymphocytes perform roles such as coordinating immune responses and directly killing infected or abnormal cells.

SEE ALSO