The 9C10 (MFR4.B) monoclonal antibody specifically binds to the Integrin α4 chain (CD49d), which is expressed as a heterodimer with either of two β chains, β1 or β7. The α4β1 integrin (VLA-4, CD49d/CD29) is expressed on most peripheral lymphocytes, thymocytes, and monocytes; while the α4β7 integrin (LPAM-1) is expressed on peripheral lymphocytes, but on only a small subset of thymocytes. These integrins mediate a variety of cell-cell and cell-matrix interactions, recognizing the ligands VCAM-1 (CD106) and fibronectin. Integrin α4β7 also preferentially binds to the mucosal vascular addressin, MAdCAM-1. Although the 9C10 (MFR4.B) antibody alone has been reported to have little function-blocking activity, it can augment the inhibitory effects of mAb R1-2 (Cat. No. 553153), resulting in almost complete inhibition of VLA-4 binding to VCAM-1.
The antibody was conjugated to BD Horizon™ BB700, which is part of the BD Horizon Brilliant™ Blue family of dyes. It is a polymer-based tandem dye developed exclusively by BD Biosciences. With an excitation max of 485 nm and an emission max of 693 nm, BD Horizon BB700 can be excited by the 488 nm laser and detected in a standard PerCP-Cy™5.5 set (eg, 695/40-nm filter). This dye provides a much brighter alternative to PerCP-Cy5.5 with less cross laser excitation off the 405 nm and 355 nm lasers.