|Detection of Human SIRP alpha /CD172a by Western Blot. Western blot shows lysates of human granulocytes. PVDF Membrane was probed with 2 µg/mL of Mouse Anti-Human SIRP alpha /CD172a Monoclonal Antibody (Catalog # MAB4546) followed by HRP-conjugated Anti-Mouse IgG Secondary Antibody (Catalog # HAF007). A specific band was detected for SIRP alpha /CD172a at approximately 70 kDa (as indicated). This experiment was conducted under non-reducing conditions and using Immunoblot Buffer Group 1.|
|Detection of SIRP alpha /CD172a in U937 Human Cell Line by Flow Cytometry. U937 human histiocytic lymphoma cell line was stained with Mouse Anti-Human SIRP alpha /CD172a Monoclonal Antibody (Catalog # MAB4546, filled histogram) or isotype control antibody (Catalog # MAB0041, open histogram), followed by Allophycocyanin-conjugated Anti-Mouse IgG F(ab')2 Secondary Antibody (Catalog # F0101B).|
|SIRP alpha /CD172a in THP‑1 Human Cell Line. SIRP alpha /CD172a was detected in immersion fixed THP‑1 human acute monocytic leukemia cell line using Mouse Anti-Human SIRP alpha /CD172a Monoclonal Antibody (Catalog # MAB4546) at 10 µg/mL for 3 hours at room temperature. Cells were stained using the NorthernLights™ 557-conjugated Anti-Mouse IgG Secondary Antibody (red; Catalog # NL007) and counterstained with DAPI. Specific staining was localized to cell membranes. View our protocol for Fluorescent ICC Staining of Non-adherent Cells.|
SIRP alpha (Signal regulatory protein alpha; also SHPS1 and BIT) is a variably glycosylated 90-120 kDa member of the SIRP family of proteins. It is widely expressed, being found on neurons, microglia/macrophages, endothelium, and fibroblasts. SIRP alpha has a variety of functions, including presynsptic organization, inhibition of integrin action, and induction of myogenesis. It binds to CD47 and likely other ligands. Mature human SIRP alpha is a 477 amino acid (aa) type I transmembrane glycoprotein. It contains an extracellular region (aa 27-372) that shows one V-type Ig-like (aa 32-137) and two C2-type Ig-like domains (aa 147-347). Its cytoplasmic domain possesses two ITIMs which interact with protein tyrosine phosphatases. There is one alternative start site at Met102 plus a four aa insertion after Gln421. Over aa 27-370, human SIRP alpha shares 61% aa identity with mouse SIRP alpha.