Anti-Human CD47 antibody (Urab

Urabrelimab (SRF231) 是一种完全人抗 CD47 单克隆抗体，可阻断 CD47-SIRP 相互作用。Urabrelimab (SRF231) is a fully human anti-CD47 monoclonal antibody that blocks the CD47-SIRP interaction

anti-CD47 monoclonal antibody SRF231
A human monoclonal antibody targeting the human cell surface antigen CD47, with potential phagocytosis-inducing and antineoplastic activities. Upon administration, anti-CD47 monoclonal antibody SRF231 selectively binds to CD47 on tumor cells and blocks the interaction of CD47 with signal regulatory protein alpha (SIRPalpha), an inhibitory protein expressed on macrophages. This prevents CD47/SIRPalpha-mediated signaling and abrogates the CD47/SIRPa-mediated inhibition of phagocytosis. This induces pro-phagocytic signaling mediated by the binding of calreticulin (CRT), which is specifically expressed on the surface of tumor cells, to low-density lipoprotein (LDL) receptor-related protein (LRP), expressed on macrophages. This results in macrophage activation and the specific phagocytosis of tumor cells. In addition, blocking CD47 signaling activates both an anti-tumor T-lymphocyte immune response and T-cell-mediated killing of CD47-expressing tumor cells. CD47, also called integrin-associated protein (IAP), is a tumor-associated antigen (TAA) expressed on normal, healthy hematopoietic stem cells (HSCs) and overexpressed on the surface of a variety of cancer cells. Expression of CD47, and its interaction with SIRPalpha, leads to the inhibition of macrophage activation and protects cancer cells from phagocytosis, which allows cancer cells to proliferate.

CD47 is overexpressed in various types of cancers and it can directly bind with SIRPα, which is mainly located on macrophages. The binding of CD47-SIRPα transmits a “don't eat me” signal, which can prevent cancer cells from immune clearance. In this case, the comprehensive understandings of the regulation of CD47 in cancer cells are essential for further developments. In this review, based on the current reports, we summarized that CD47 expression could be regulated by cytokines, oncogenes, microRNAs and enzymes in cancer cells. Likewise, CD47 expression could be regulated at the transcriptional level, post-transcriptional level, post-translational modification level, etc. However, further studies are required to determine other factors that regulate CD47 expression.

•Cytokines, oncogenes, microRNAs and enzymes regulate CD47 expression in cancer.

•CD47 expression could be regulated at the transcriptional, post-transcriptional and post-translational modification level.

•Further studies are required to determine other factors that regulate CD47 expression.