News - Cytokine Key In Clinical Activity In Rheumatoid Arthritis

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Cytokine Key In Clinical Activity In Rheumatoid Arthritis

A DGReview of : " Macrophage migration inhibitory factor in rheumatoid

arthritis: clinical correlations "

Rheumatology Online

05/30/2002

By Anne MacLennan

Synovial expression of macrophage migration inhibitory factor is strongly

correlated with clinical disease activity in patients with rheumatoid

arthritis.

This finding from a joint study in Australia and the United States adds

significant weight to evidence for the importance of this cytokine's role in

rheumatoid arthritis (RA).

In fact, migration inhibitory factor is an important member of the cytokine

hierarchy in this disease, suggest these researchers from Monash Medical

Centre, Melbourne, Repatriation General Hospital, Adelaide, and Picower

Institute for Medical Research, Manhasset, New York.

Cytokines are known to be key in the pathology of RA, and MIF is one with a

broad spectrum of actions. These include induction of monocyte tumour

necrosis factor a (TNF-a).

MIF expression and proinflammatory activity in RA synovium and in animal

models of the disease has been demonstrated recently. However, E. F. Morand

and colleagues sought to assess the link between synovial MIF and clinical

disease.

Using paired sample from eight patients with active and inactive/treated

disease, the researchers compared computer-assisted analysis of cytokine

content of arthroscopically obtained biopsies of RA synovium with documented

clinical parameters.

Synovial MIF immunostaining correlated strongly with disease activity as

measured by CRP concentration.

Moreover, significant reductions in synovial MIF were found to accompany

reductions in clinical disease parameters, including CRP, and tender and

swollen joint counts.

Synovial TNF-a, transforming growth factor b (TGF- and interleukin (IL)10

also showed a significant reduction in association with reduced disease

activity; IL-1b and IL-1 receptor agonist did not.

The demonstration that only MIF and TNF-a show significant variation in

synovial cytokine content with clinical remission points to MIF' s

importance in the cytokine hierarchy in RA, these authors conclude.

Rheumatology 2002; 41: 558-562