B cells

From WikiVet English
Jump to navigation Jump to search

B Cells in Lymph node

©RVC 2008

Also known as B lymphocytes

So named as they were initially found in the Bursa of Fabricius, B cells produce antibodies and are associated with humoral immunity (T cells are part of the cell-mediated immune response), and are an integral part of the adaptive immune system. They represent 20-30% of circulating lymphocytes.

B cells have cell surface proteins known as B cell receptors (BCRs) that are known as immunoglobulins; IgM is the membrane bound BCR that is expressed when the B cell is immature, changing to IgD when the cell is mature. IgM has a large molecular mass and can bind up to 10 antigens simultaneously. B cells also express MHC II, CD9, CD,19, CD20 and CD24.

Under antigenic stimulation B cells differentiate into plasma cells and memory cells.

B-cells also act as Antigen-Presenting Cells (APCs) by presenting digested fragments to T cells on MHC II.

LIVE logo Originally funded by the RVC Jim Bee Award 2007

WikiVet® Introduction - Help WikiVet - Report a Problem