Effect of antirheumatic drugs on lymphocyte membrane fluidity in rheumatoid arthritis: a fluorescence polarization study.

We have demonstrated significant differences in 1,6-diphenyl-1,3,5-hexatriene fluorescence polarization values between lymphocyte membranes of untreated rheumatoid arthritis patients and lymphocyte membranes of patients treated with antirheumatic drugs, such as hydroxychloroquine and auranofin. No difference has been detected in rheumatoid arthritis patients treated with auranofin associated with 6-methylprednisolone. The results indicate that some drugs used in the treatment of rheumatoid arthritis induce changes of lymphocyte membrane fluidity. The positive correlations between fluorescence polarization values and objective indices of the disease activity, as erythrocyte sedimentation rate, C-reactive protein, fibrinogen level, and alpha 2-globulin, suggested that fluorescence polarization could be used in the study of the pharmacological action of antirheumatic drugs and in monitoring antirheumatic therapy.