Recombinant Human CD40 (TNFRSF5)-Fc Chimera (carrier-free) 100 µg

CD40, also known as TNFRSF5, is a type I transmembrane protein that belongs to the TNF receptor family (TNFR). CD40 is expressed on B cells, dendritic cells, monocytes, macrophages, platelets, basal epithelial cells, endothelial cells and a subset of CD34⁺ hematopoietic progenitors. The interaction between CD40 and its ligand TNFSF5/CD40L leads to the clustering of CD40 and the recruitment of TNFR associated factors (TRAFs), including TRAF1, 2, 3, 5 and 6. TRAF1, 2, 5 and 6 serve as positive regulators while TRAF3 is a negative regulator. CD40/CD40L interaction triggers downstream signaling on both cells, including upregulation of CD40 and cell survival on dendritic cells, upregulation of co-stimulatory molecules, CD80 and CD86 on T cells, and production of inflammatory cytokines. In addition, CD40 regulates B cell development/maturation, Ig isotype switching and in combination with other signals such as IL-4, promotes proliferation. It has been reported that a transcriptional factor, AKNA, can coordinately regulate the expression of CD40 and CD40L. Dysregulation of CD40 is associated with several diseases, such as hyper-IgM immunodeficiency type 3 (HIGM3) and Hodgkin's disease. Targeting of CD40/CD40L for cancer therapy is being evaluated in clinical trials, including anti-CD40 agonist antibodies and soluble recombinant CD40L. Several isoforms have been identified in human and mice.;