Classification system devised to provide
standard names for the various
functional groups of
proteins on a cell surface. CD stands for 'cluster of
differentiation'. The system is reviewed, and new CD designations added or updated, at the Human
Leucocyte Differentiation
Antigen workshop which is held every year.
The CD classification system is now the accepted norm for formal designation of cell surface molecules. It has superceded previous systems, such as naming cell surface molecules according to the particular function affected by an anti-leukocyte monoclonal antibody to that molecule, or simply allowing the research group that discovered the molecule to name it.
An example of the CD system is CD14.