The Relation Between Macrophage Migration Inhibitory Factor (MIF) and 25(OH) Vitamin D3 Serum Levels in Rheumatoid Arthritis

Although the pathogenesis of Rheumatoid Arthritis is multifactorial, the contribution of cytokines is undoubtedly pivotal in the progression of the inflammatory process. One cytokine gaining recognition for its importance in the inflammatory process is Macrophage migration inhibitory factor .

Macrophage Migration Inhibitory Factor is a multipotent cytokine involved in a broad range of functions including induction of proinflammatory mediators as well as demonstrated roles in both innate and adaptive immunity. It was originally identified in the culture medium of activated T lymphocytes as a soluble factor that inhibit random migration of macrophages .

Macrophage Migration Inhibitory Factor induces synoviocytes expression of key proinflammatory genes including TNF, IL-1, IL-6, IL-8. Moreover, it also regulates the function of endothelial cells and B cells and is implicated in the control of synoviocytes proliferation and apoptosis via direct effects on the expression of the tumor suppressor protein P53. In Rheumatoid Arthritis, increased Macrophage Migration Inhibitory Factor levels have been demonstrated in serum, synovial fluid and tissue correlating with disease activity.

Hydroxyapatite 25 vitamin D3 is a hormone primarily synthesized in human skin under the stimulation of ultraviolet radiation. Beyond its endocrine role in bone metabolism, Vitamin D3 is endowed with remarkable immunomodulatory properties. The effects of Vitamin D3 on the immune system include the enhancement of microbicidal ability of monocytes macrophages and the down-modulation of inflammatory cytokines produced by T lymphocytes.

Some epidemiological studies have reported an inverse association between serum 25(OH)vitamin D3 concentrations and Rheumatoid Arthritis disease activity and severity. In addition, some studies have reported inverse correlations between serum 25(OH)vitamin D3 and circulating inflammatory markers and cytokines.