In accordance with studies demonstrating that polymorphisms that increase aminopeptidase activity predispose to immune disease, the increased risk also attributed to increased expression of ERAP1 and ERAP2 supports the notion of using aminopeptidase inhibition to treat AS and other ERAP-associated conditions.
Previous studies show that endoplasmic reticulum-associated aminopeptidase (ERAP1/ERAP2) and runt-related transcription factor 3 (RUNX3) gene polymorphisms are associated with AS (ankylosing spondylitis) in European Caucasians.
Endoplasmic reticulum (ER) aminopeptidase 1 (ERAP1) variants contribute to the risk of ankylosing spondylitis in HLA-B27 positive individuals, implying a disease-related interaction between these gene products.
Discovery of the association of aminopeptidase genes with AS, and subsequently with psoriasis, inflammatory bowel disease and other conditions, has triggered research into therapies targeting this pathway.
It was found that single nucleotide polymorphisms (SNPs) of endoplasmic reticulum aminopeptidase (ERAP1 and ERAP2) genes influence the risk of ankylosing spondylitis, the most common form of SpA and the risk of psoriasis.
A key aminopeptidase in class I major histocompatibility complex presentation, ERAP1 potentially contributes to the pathogenesis of AS by altering HLA-B27 peptide presentation.
We also show that polymorphisms of ERAP1, which encodes an endoplasmic reticulum aminopeptidase involved in peptide trimming before HLA class I presentation, only affect ankylosing spondylitis risk in HLA-B27-positive individuals.