Lymphocyte Antigen 75 (LY75)

The LY75 protein has 77% overall amino acid identity with mouse Dec205. LY75 is a member of the MMR family of multidomain molecules. It contains a signal peptide, a cysteine-rich domain, a fibronectin type II domain, 10 carbohydrate recognition-like domains, a transmembrane domain, and a cytoplasmic tail. Northern blot analysis of hematopoietic cell lines revealed the presence of a predominant 7.8-kb and a secondary 9.5-kb transcript in myeloid, B-cell, and Hodgkin cell lines but not in the Jurkat T-cell line. In peripheral blood, immature DC contained barely detectable transcripts, which increased 50-fold upon differentiation and activation.LY75 acts as an endocytic receptor to direct captured antigens from the extracellular space to a specialized antigen-processing compartment.