The HSL96 monoclonal antibody specifically recognizes CD179a which is also known as VpreB (V pre beta/V pre β). CD179a (VpreB) is a ~18 kDa, Ig V domain-like protein that is encoded by VPREB1 (pre-B lymphocyte 1). This member of the immunoglobulin (Ig) gene superfamily is primarily expressed in the cytoplasm of normal pro-B and early pre-B cells and at low levels on the surface of early pre-B cells. It is not expressed by normal mature circulating B cells or by other leucocyte populations. CD179a (VpreB) associates noncovalently with CD179b (λ5) to form CD179a/CD179b (VpreB/ λ5), an Ig light chain-like structure called the surrogate light chain. Surrogate light chains are disulfide-linked to membrane-bound IgM heavy chains in association with signal transducer CD79a/CD79b heterodimers which together form the pre-B cell receptor (preBCR) complex. The preBCR plays a critical role in early B cell proliferation and differentiation. The HSL96 antibody can reportedly be used to stain cytoplasmic and cell surface CD179a (VpreB).
The antibody was conjugated to BD Horizon BV421 which is part of the BD Horizon Brilliant™ Violet family of dyes. With an Ex Max of 407-nm and Em Max at 421-nm, BD Horizon BV421 can be excited by the violet laser and detected in the standard Pacific Blue™ filter set (eg, 450/50-nm filter). BD Horizon BV421 conjugates are very bright, often exhibiting a 10 fold improvement in brightness compared to Pacific Blue conjugates.