Moura, Rita A.Weinmann, PamelaPereira, Patrícia A.Caetano-Lopes, JoanaCanhao, HelenaSousa, ElsaMourão, Ana F.Rodrigues, Ana M.Queiroz, Mário V.Souto-Carneiro, Maria M.Graca, LuisFonseca, João Eurico2012-04-162012-04-162010-03-07Rheumatology 2010;49:1082–10921462-0324http://hdl.handle.net/10451/5992doi:10.1093/rheumatology/keq029©The Author 2010. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved.Objective. To characterize circulating B-cell subpopulations of arthritis patients with <6 weeks of disease duration. Methods. Peripheral blood samples were collected from very early untreated polyarthritis patients, with <6 weeks of disease duration, for flow cytometric evaluation of B-cell subpopulations. Samples from patients who were later diagnosed as RA [very early RA (VERA)] were also collected 4–6 weeks after starting a low dose of prednisone (5–10 mg) and 4 months after reaching the minimum effective dose of MTX. A matched healthy group was used as a control. Results. VERA patients have a lower percentage of total peripheral blood memory B cells (CD19+CD27+) and a significant decrease in the frequency of circulating pre-switch memory B cells (CD19+IgD+CD27+) as compared with controls. Therapy with corticosteroids or MTX was unable to restore the normal frequencies of these B-cell subpopulations. A significant decrease in peripheral pre-switch memory B cells is equally observed in other early arthritis patients. Furthermore, no significant differences are found in the frequencies of CD4+ and CD8+ T cells in all patient groups. Conclusions. In very early polyarthritis patients, there is a reduction in circulating pre-switch memory B cells. The reasons that may account for this effect are still unknown. Short-term corticosteroids and MTX do not seem to have a direct effect on circulating B-cell subpopulations in VERA patients.engRheumatoid arthritisB cellsCorticosteroidsMethotrexateAutoimmunityjournal article