In particular, the aberrant expression of the allele of the HLA B 27 in spondylitis, could act by binding cells that contain a natural killer receptor for HLA B 27 homodimer, named killer cell immunoglobulin-like receptor 3DL2 (KIR3DL2), determining IL-17 production (104). This evidence concerns the gene KIR3DL2 and spondylitis.