BD Transduction Laboratories™ Purified Mouse Anti-HAX-1

Cell-cell interactions in the immune system, mediated by membrane-bound antigen receptors, trigger a cascade of signaling mechanisms collectively known as the T-cell response. Upon antigen binding, cellular tyrosine kinases are activated resulting in the phosphorylation of HS1 or Lck-binding protein 1 (LckBP1), which is involved in thymic negative selection. HS1 is one of the earliest intracellular proteins to be tyrosine phosphorylated in response to antigen-receptor cross-linking in T cells. HAX-1 (HS1-associated protein X-1) is a 35 kDa protein found associated with HS1 by co-immunoprecipitation assays and the two-hybrid system. HAX-1 is ubiquitously expressed and localized in the mitochondria, endoplasmic reticulum, and the nuclear envelope. The HS1-HAX-1 complex may be critical for signal transduction pathways initiated by antigen presentation to T cells.