Anti-CD74 Antibody

HLA class II histocompatibility antigen gamma chain also known as HLA-DR antigens-associated invariant chain or CD74 (Cluster of Differentiation 74), is a protein that in humans is encoded by the CD74 gene. The protein encoded by this gene associates with class II major histocompatibility complex (MHC) and is an important chaperone that regulates antigen presentation for immune response. It also serves as cell surface receptor for the cytokine macrophage migration inhibitory factor (MIF) which, when bound to the encoded protein, initiates survival pathways and cell proliferation. This protein also interacts with amyloid precursor protein (APP) and suppresses the production of amyloid beta (Abeta) . Multiple alternatively spliced transcript variants encoding different isoforms have been identified.

Isoform 1 and isoform 2 are detected in bone marrow cells, spermatogonia and spermatocytes, but not in round spermatids, elongating spermatids and spermatozoa. Isoform 3 is detected in round spermatids, elongating spermatids and spermatozoa, but not in spermatogonia and spermatocytes (at protein level) . Isoform 1 is widely expressed and detected in fetal liver and bone marrow. Isoform 3 is detected in bone marrow cells enriched in hematopoietic stem cells.

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1. Claesson, L., Larhammar, D., Rask, L., Peterson, P. A. cDNA clone for the human invariant gamma chain of class II histocompatibility antigens and its implications for the protein structure. Proc. Nat. Acad. Sci. 80: 7395-7399, 1983. 2. Claesson-Welsh, L., Barker, P. E., Larhammar, D., Rask, L., Ruddle, F. H., Peterson, P. A. The gene encoding the human class II antigen-associated gamma chain is located on chromosome 5. Immunogenetics 20: 89-93, 1984. 3. Driessen, C., Bryant, R. A., Lennon-Dumenil, A. M., Villadangos, J. A., Bryant, P. W., Shi, G. P., Chapman, H. A., Ploegh, H. L. Cathepsin S controls the trafficking and maturation of MHC class II molecules in dendritic cells. J. Cell Biol. 147: 775-790, 1999.

Store at -20°C for one year from date of receipt. After reconstitution, at 4°C for one month. It can also be aliquotted and stored frozen at -20°C for six months. Avoid repeated freeze-thaw cycles.