The GAME-46 monoclonal antibody specifically binds to CD18. CD18 is the common β2 integrin chain of LFA-1 (CD11a/CD18, αLβ2 integrin), Mac-1 (CD11b/CD18, αMβ2 integrin), and gp150, 95 (CD11c/CD18, αXβ2 integrin). Expression of CD18 is limited to leucocytes, where it is widely distributed in consort with each of the three integrin α chains (CD11a, CD11b, and CD11c). Among splenocytes, NK cells have the highest density of CD18, and T lymphocytes express a higher density than the remaining cells. The β2 integrins are important mediators of leukocyte-endothelium interactions. It has been reported that GAME-46 antibody blocks in vitro adhesion of LFA-1-expressing cells to the ligands ICAM-1, ICAM-2 and ICAM-3 and of Mac-1-expressing cells to ICAM-1, C3bi, and fibrinogen.
The antibody was conjugated to BD Horizon™ BUV496 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome of BD Horizon BUV395 with an Ex Max of 348-nm and an acceptor dye with an Em Max at 496-nm. BD Horizon BUV496 can be excited by the ultraviolet laser (355 nm) and detected with a 515/30 nm filter with a 450LP. Due to the excitation of the acceptor dye by other laser lines, there may be significant spillover into the channel detecting BD Horizon V500 or BV510 (eg, 525/40-nm filter). However, the spillover can be corrected through compensation as with any other dye combination.