Inhibition of ERAP1 represses HLA-B27 free heavy chains expression on polarized macrophages and interrupts NK cells activation and function from ankylosing spondylitis.

Background: We aimed to assess if Endoplasmic reticulum aminopeptidase 1 (ERAP1) polymorphisms might impress Human leukocyte antigen (HLA)-B27-free heavy chains (FHCs) expression on macrophages and eventually NK cell activation in Ankylosing spondylitis (AS).

Methods: Blood samples were obtained from 10 HLAB27 patients with protective and 10 HLAB27 patients with non-protective genotype. Monocytes were isolated and polarized toward M1 and M2 macrophages.

Evaluation of ERAP1 gene single nucleotide polymorphisms in immunomodulation of pro-inflammatory and anti-inflammatory cytokines profile in ankylosing spondylitis.

Background: Ankylosing spondylitis (AS) is a prototype of chronic inflammatory arthritis termed seronegative spondyloarthropathies that typically affects the joints. Among the non-Human leukocyte antigen (HLA) loci, the strongest association has been observed with Endoplasmic reticulum aminopeptidase 1 (ERAP1) gene single nucleotide polymorphisms (SNPs). Moreover, the effect of ERAP1 gene SNPs on the pro-inflammatory and anti-inflammatory cytokines in AS disease has still been poorly elucidated.