reported strong expression of HIF-1α in the intimal layer of macrophage-like synoviocytes (MLS) in human RA synovium (128), while HIF-2α is mainly expressed in fibroblast-like synoviocytes (FLS) in human RA synovium and collagen-induced arthritis model (CIA) (129). The gene discussed is HIF1A; the disease is rheumatoid arthritis.