Recombinant Human CD74 Protein, CF

Recombinant Human CD74 Protein, CF Summary

• R&D Systems CHO-derived Recombinant Human CD74 Protein (3590-CDB)
• Quality control testing to verify active proteins with lot specific assays by in-house scientists
• All R&D Systems proteins are covered with a 100% guarantee

Product Specifications

Product Datasheets

Carrier Free

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

Background: CD74

CD74, also known as Invariant chain (Ii) and p33, is a type 2 transmembrane glycoprotein that plays an important role in adaptive immunity, inflammation, and cancer (1). Mature human CD74 consists of a 46 amino acid (aa) cytoplasmic domain, a 26 aa transmembrane segment, and a 224 aa extracellular domain (ECD) that contains one thyroglobulin type 1 domain (2, 3). Alternate splicing and the use of a second initiation start site result in the synthesis of additional isoforms (ranging from 31 kDa ‑ 41 kDa) that differ by the presence or absence of a 16 aa N‑terminal extension and/or a 64 aa internal section of the ECD (4). This recombinant protein does not contain the 64 aa insertion. Within comparable regions of the ECD, human CD74 shares 70% and 73% aa sequence identity with mouse and rat CD74, respectively. CD74 functions as a chaperone for MHC class II molecules on antigen presenting cells and undergoes progressive proteolysis during class II trafficking and antigenic peptide loading (5). Full length CD74 assembles into trimers which then associate with class II molecules in nonameric complexes on the cell surface (6, 7). CD74 also associates with CD44 and binds with high affinity to the cytokine MIF, leading to inflammatory leukocyte responses, protection from tissue fibrosis, B cell proliferative and survival signaling, and the up‑regulation of angiogenic factors in endometrial stromal cells (8 ‑ 13). MIF binding notably induces the proteolytic cleavage of the CD74 intracellular domain which then promotes B cell differentiation (12). CD74 is up‑regulated on non‑immune cells at sites of inflammation including amyloid beta plaques and atherosclerotic plaques (14, 15). It is also up‑regulated in a variety of cancers and enhances tumorigenicity, tumor angiogenesis, and metastasis (1, 16).

Related Research Areas

• Cancer Biomarkers
• Dendritic Cell Pathogen Recognition/Uptake
• Epithelial Cell Markers and Intracellular Molecules
• Microglia Development
• Surface Ectodermal Cells