<b>Methods:</b> PBMCs from 18 patients with active AS and 18 healthy individuals were separated by Ficoll-Hypaque density gradient centrifugation and cultured in the presence of muramyl dipeptide (MDP), as NOD2 ligand.
The association with HLA-B27 is less strong in IBD-associated SpA than in Idiopathic Ankylosing Spondylitis (AS) and there is some evidence for an association between gut inflammation in SpA and CD related CARD15 mutations.
The 3 most common CD NOD2 mutations do not contribute to disease susceptibility to AS, and therefore do not explain the susceptibility locus for AS in chromosome 16q.