It binds to CD2 (LFA-2)  on T cells and is important in strengthening the adhesion between the T cells and Professional Antigen Presenting Cells. This adhesion occurs as part of the transitory initial encounters between T cells and Antigen Presenting Cells before T cell activation, when T cells are roaming the lymph nodes looking at the surface of APCs for peptide:MHC complexes the T-cell receptors are reactive to.
Polymorphisms in the CD58 gene are associated with increased risk for multiple sclerosis.
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