HEMOGLOBIN LEVELS CORRELATE WITH SERUM-SOLUBLE CD23 AND TNF-RS CONCENTRATIONS IN PATIENTS WITH RHEUMATOID-ARTHRITIS

The present study was designed to investigate the possible relationshi ps of hemoglobin concentrations with serum levels of soluble CD23 mole cules (sCD23) and soluble tumor necrosis factor receptors I and II (sT NF-RI and sTNF-RII) in rheumatoid arthritis (RA) patients. Fifty-six p atients, eight males and 48 females, and 20 age and sex matched health y volunteers were enrolled in the study. Patients were classified in t wo groups on the basis of disease activity: group A included 43 patien ts with active, and group B 13 patients with non-active RA. Serum sCD2 3 and sTNF-Rs levels were measured using commercially available micro- ELISA kits. It was found that patients of group A had lower hemoglobin concentrations than patients of group B or normal controls, whereas h emoglobin levels in patients of group B did not differ statistically f rom the controls. Patients of group A had also significantly higher se rum sCD23, sTNF-RI and sTNF-RII concentrations than patients of group B or control subjects. Serum levels of all three cytokines did not dif fer statistically between patients of group B and normal controls. In the entire group of subjects studied, hemoglobin concentrations correl ated inversely with the levels of serum sCD23, sTNF-RI and sTNF-RII, a nd also with the values of the erythrocyte sedimentation rate (ESR) an d C-reactive protein (CRP) reflecting disease activity. We concluded t hat anemia and elevated concentrations of sCD23, sTNF-RI and sTNF-RII in RA patients are two biological expressions of the same underlying i nflammatory process, although a causal relationship between themselves cannot be excluded and needs further investigation.