Immunological studies in patients with rheumatoid arthritis treated with methotrexate or cyclophosphamide

One-hundred-and-two-patients (pts) with rheumatoid arthritis (RA) were observed for 12 months. Forty-eight pts were treated with a weekly low-dose of methotrexate (MTX), 23 pts with cyclophosphamide (CTX) (eight pts with one single intravenous dose, and 15 pts orally with a single daily dose), and 31 pts with nonsteroidal antiinflammatory drugs (NSAID) only. In all individuals acute phase response, i.e., C-reactive protein (CRP) and alpha-1-acid glycoprotein (AGP) serum levels, and AGP microheterogeneity using affinoimmunoelectrophoresis with concanavalin A were evaluated. The phenotype of lymphocytes isolated from peripheral blood was characterized using immunofluorescence technique. Following treatment the increased level of CRP significantly decreased whereas AGP serum level remained unchanged. Among the patients, microheterogeneity of AGP expressed as reactivity coefficient (RC) was lower before treatment when compared with 17 controls (0.95 +/- 0.23 vs. 1.35 +/- 0.15, p < 0.01). After 12 months of MTX therapy AGP-RC rose significantly (1.19 +/- 0.13, p < 0.01). No changes were observed in AGP-RC levels in CTX and NSAID treated individuals. No significant differences were observed in the percentage of CD3+, CD4+, and CD8+ cells in all the patient groups, except in CTX intravenously treated patients. In this group of patients a decrease of CD4+ cells was noticed (60.1 +/- 11.5% and 43.8 +/- 12.5% before and after treatment respectively -p < 0.01). The percentage of CD19 positive cells decreased significantly during 12 months of treatment with MTX and CTX. The percentage of activated T cells (CD25+ cells and HLA-DR+ cells) remained unchanged in MTX treated patients and was reduced in both CTX groups.(ABSTRACT TRUNCATED AT 250 WORDS)