The aim of this study was to evaluate the relationship between serum chemokines and the clinical and radiological response to a one-year course of methotrexate (MTX) in patients suffering from rheumatoid arthritis (RA).
Twenty out-patients suffering from active RA entered a one-year open prospective study on the effects of low dose MTX therapy. Plain radiographs of the hands and feet were taken at study entry and at the end of the follow-up, and were compared for the number of eroded joints. Serum levels of both C-X-C and C-C chemokines were obtained before the initation of MTX and after 6 and 12 months of treatment.
The levels of serum RANTES before treatment were significantly higher in RA patients than in the controls and returned to normal levels after one year of treatment. Serum levels of the other chemokines were either in the normal range or undetectable. Twelve patients (60%) did not show any new eroded joints at the end of the follow-up period and were considered as radiological responders (RR). Serum levels of GRO-alpha and RANTES after 6 months of treatment were significantly higher among the patients with radiological progression than in RR patients.
We observed high levels of serum RANTES in a series of RA patients during the active stage of the disease. MTX treatment significantly lowered the serum levels of RANTES, GRO-alpha and MCP-1. High levels of serum RANTES or GRO-alpha after 6 months of MTX treatment seem to be predictive of radiological erosions after one year.