CD5+ B lymphocyte

https://doi.org/10.1351/goldbook.12975
Lymphocyte of type B-1a, which is predominant in fetal lymphoid organs and in neonatal cord blood.
Notes:
  1. In adults, these cells range from \(\pu{2}\) to \(\pu{6\%}\) of total mononuclear cells in peripheral blood. They utilize an immunoglobulin (Ig) variable (V) gene repertoire different from that of CD5– B cells and they produce natural autoantibodies.
  2. The expansion of autoreactive B1-a cells has been reported in peripheral blood of patients with autoimmune diseases [e.g., rheumatoid arthritis (RA), Sjögren syndrome, antiphospholipid syndrome (APS)]. In RA these cells can account for up to \(\pu{20\%}\) of circulating B cells and may produce rheumatoid factor.
Source:
PAC, 2012, 84, 1113. (IUPAC glossary of terms used in immunotoxicology (IUPAC Recommendations 2012)) on page 1138 [Terms] [Paper]