Phosphorylcholine

This article is about the functional group derived from phosphocholine. For the class of phospholipids that incorporate choline as a headgroup, see phosphatidylcholine.

Phosphorylcholine (abbreviated ChoP) is the hydrophilic polar head group of some phospholipids, which is composed of a negatively charged phosphate bonded to a small, positively charged choline group. Phosphorylcholine is part of the platelet-activating factor; the phospholipid phosphatidylcholine and sphingomyelin, the only phospholipid of the membrane that is not built with a glycerol backbone.[1] Treatment of cell membranes, like those of RBCs, by certain enzymes, like some phospholipase A2, renders the phosphorylcholine moiety exposed to the external aqueous phase, and thus accessible for recognition by the immune system.[2] Antibodies against phosphorylcholine are naturally occurring autoantibodies that are created by CD5+/B-1 B cells and are referred to as non-pathogenic autoantibodies.[3]

  1. ^ Karp, Gerald (2010). Cell and molecular biology : concepts and experiments (6 ed.). Hoboken, NJ: John Wiley. pp. 48, 123. ISBN 978-0-470-48337-4. OCLC 432406854.
  2. ^ Beckmann, E.; Bach, M. A.; et al. (1984). "Phosphorylcholine on isologous red blood cells induces polyclonal but not anti-phosphorylcholine plaque-forming cells in mice". Eur J Immunol. 14 (7): 595–598. doi:10.1002/eji.1830140703. PMID 6378644. S2CID 37626179.
  3. ^ Hardy, Richard (2008). "Chapter 7: B Lymphocyte Development and Biology". In Paul, William (ed.). Fundamental Immunology (Book) (6th ed.). Philadelphia: Lippincott Williams & Wilkins. pp. 237–269. ISBN 978-0-7817-6519-0.