The 14-4-4S monoclonal antibody specifically recognizes the I-E[k] MHC class II alloantigen. It crossreacts with cells from mice of the H-2[d], H-2[p], and H-2[r] haplotypes. Cells from mice of the H-2[b], H-2[f], H-2[g7], H-2[q], and H-2[s] haplotypes do not express I-E antigen. It has been reported that mAb 14-4-4S crossreacts with the rat MHC class II antigen RT1D.
The antibody was conjugated to BD Horizon BUV615 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome with an Ex Max near 350 nm and an Em Max near 615 nm. BD Horizon Brilliant BUV615 can be excited by the ultraviolet laser (355 nm) and detected with a 610/20 filter and a 595 nm LP. Due to the excitation of the acceptor dye by the blue/yellow-green laser line, there may be significant spillover into channels detecting PE-CF594 like emissions (eg, 610/20-nm filter).