B-Lipo
This article is about the immune system cell. For the electrical cell, see Battery (vacuum tube). For β-cell of pancreas, see beta cell.
B lymphocyte cell
Human B Lymphocyte (28942386960).jpg
Transmission electron micrograph of a human B cell
Details
System Immune system
Identifiers
Latin lymphocytus B
MeSH D001402
FMA 62869
Anatomical terms of microanatomy
[edit on Wikidata]
Basic B cell function: bind to an antigen, receive help from a cognate helper T cell, and differentiate into a plasma cell that secretes large amounts of antibodies
3D rendering of a B cell
B cells, also known as B lymphocytes, are a type of white blood cell of the lymphocyte subtype.[1] They function in the humoral immunity component of the adaptive immune system.[1] B cells produce antibody molecules; however, these antibodies are not secreted. Rather, they are inserted into the plasma membrane where they serve as a part of B-cell receptors.[2] When a naïve or memory B cell is activated by an antigen, it proliferates and differentiates into an antibody-secreting effector cell, known as a plasmablast or plasma cell.[2] Additionally, B cells present antigens (they are also classified as professional antigen-presenting cells (APCs)) and secrete cytokines.[1] In mammals, B cells mature in the bone marrow, which is at the core of most bones.[3] In birds, B cells mature in the bursa of Fabricius, a lymphoid organ where they were first discovered by Chang and Glick,[3] which is why the ‘B’ stands for bursa and not bone marrow as commonly believed.
B cells, unlike the other two classes of lymphocytes, T cells and natural killer cells, express B cell receptors (BCRs) on their cell membrane.[1] BCRs allow the B cell to bind to a specific antigen, against which it will initiate an antibody response.[1]