Rabbit anti Human IRAK1 antibody recognizes human Interleukin-1 receptor-associated kinase 1 (IRAK1) an ~80 kDa serine/threonine protein kinase designated IRAK containing a single protein kinase domain and a single death domain. IRAK is associated with IL-1 receptor subunits, and mediates a signalling cascade leading to NF-kB activation after IL-1 binding (Burns et al. 2000).Multiple isoforms of IRAK1 generated by alternative splicing have been described. Isoforms 1 and 2 are ubiquitously expressed (Jensen et al. 2001). Rabbit anti Human IRAK1 antibody recognizes isoform 1 but reactivity with other isoforms having partial deletions of the carboxy-terminal region has not been assessed.