The R19-15 antibody recognizes an epitope in the CH3 domain of mouse IgG2a, with strong reactivity to the Igh-I[a] allotype and weaker reactivity to Igh-I[b]. It does not react with other Ig isotypes. Molecular genetic analyses suggest that the Igh-I[b] allele, which encodes IgG2a[b], is derived from a locus found in several wild mouse subspecies, but not domestic mice, which encodes the IgG2c isotype.
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).