Description
The lymphocyte activation gene-3 (LAG-3, CD223), a member of the immunoglobulin superfamily (IgSF) related to CD4, binds to the major histocompatibility complex (MHC) class II molecules but with higher affinity than CD4. Several alternative mRNA splice-variants of human LAG-3 have been described, two of them encoding potential secreted forms: LAG-3V1 (i.e. the D1-D2 domains of the protein, 36 kDa) and LAG-3V3 (D1-D3, 52 kDa)