The M1/70 antibody reacts with the 170 kDa α[M] chain of Mac-1 (CD11b/CD18, α[M]β2 integrin), also known as complement receptor 3 (CR3), which mediates adhesion to C3bi and ICAM-1 (CD54). Mac-1 is expressed at varying levels on granulocytes, macrophages, myeloid-derived dendritic cells, natural killer cells, microglia, and B-1 cells. Mac-1 expression is rapidly up-regulated on neutrophils after activation, in the same time period that CD62L (L-selectin) is shed from the cell surface. M1/70 antibody reportedly blocks cell adherence and C3bi binding, but it does not block cell-mediated lysis. Cross-reaction of mAb M1/70 with CD11b on human monocytes, polymorphonuclear leukocytes, and NK cells has been reported. This antibody is routinely tested by flow cytometric analysis. Other applications were tested during antibody development only or reported in the literature. Expression of CD11b on bone-marrow myeloid cells. BALB/c bone-marrow leukocytes were stained with either purified Rat IgG2b, κ isotype control A95-1 (Cat. No. 553986, left panel) or purified M1/70 monoclonal antibodies (right panel), followed by FITC-conjugated goat anti-rat Ig (Cat. No. 554016, both panels). Please note that the population of cells having the lowest SSC (erythroid and lymphoid cells) show little expression of CD11b, while cells with moderate-to-high SSC (myeloid cells) are almost uniformly CD11b positive (right panel). Flow cytometry was performed on a BD FACScan™ flow cytometry system.
BD Pharmingen™ Purified Rat Anti-Mouse CD11b - Purified - Clone M1/70 - Isotype Rat IgG2b, κ - Reactivity Ms, Hu - 0.1 mg
Purification
The monoclonal antibody was purified from tissue culture supernatant or ascites by affinity chromatography.
Immunogène
C57BL/10 splenic T cells and concanavalin A-activated C57BL/10 splenocytes