THE LEVELS OF MEMORY (CD45RA-, RO-BLOOD T-LYMPHOCYTES CORRELATE WITH IGM RHEUMATOID FACTORS IN RHEUMATOID-ARTHRITIS() CD4+ AND CD8+ PERIPHERAL)

We investigated whether, in rheumatoid arthritis (RA), the CD45 isofor m expression of peripheral blood T-lymphocytes (T-PBL) is related to a uto-immune processes (e.g. IgM rheumatoid factors) and to clinical man ifestations. By three-colour flow cytometry, we quantified three subse ts of CD4+ or CD8+ T-PBL: ''naive'' CD45RA+,RO-, ''transient'' CD45RA,RO+, and ''memory'' CD45RA-,RO+ cells, in 102 patients with RA and in 41 age- and sex-matched controls. The serum levels of rheumatoid fact ors (RF) were determined - besides conventional agglutination tests - by ELISA (IgM-RF). Extensive clinical examination was performed at the time of blood sampling. In RA, age, sex and drug therapy did not cons titute major influences on the CD45R/RO patterns. In ''healthy'' men, higher age significantly correlated with fewer naive and more memory C D4+ T-PBL (P<0.01). In RA, distinct correlations between the T-PBL sub sets, autoimmune and clinical manifestations became obvious when patie nts with low and high levels of RF against human IgG Fc fragments, as determined by ELISA, were analysed separately. RA patients with high I gM-RF had elevated proportions of CD45RO+ T-PBL (P<0.05), that correla ted with clinical parameters of disease activity (tender joint count, Ritchie index, P<0.05) and outcome (Health Assessment Questionnaire, L arsen radiographic scores, P<0.05). The proportions of memory CD4+ and CD8+ T-PBL correlated strongly (P<0.001) with the IgM-RF levels. With in 1 year, only three of 34 patients (disease duration of 5-9 years) s howed seroconversion from low to high levels of IgM-RF (and positive a gglutination tests); this was paralleled by reductions in naive and in creases in transient T-PBL (P<0.02). Thus, in RA, the proportions of m emory CD4+ and CD8+ T-PBL correlate with the level of IgM-RF and, toge ther with transient T-PBL, with clinical parameters of disease activit y and outcome.