CXC ligand 13 in rheumatoid arthritis and its relation to secondary Sjögren’s syndrome

AbstractAim of the workThe aim of the present study was to measure the level of the chemokine CXC ligand 13 protein (CXCL13) in the plasma and unstimulated saliva of rheumatoid arthritis (RA) patients in order to find out its role in the disease activity and its relation to secondary Sjögren’s syndrome (sSS).Patients and methodsThe study was conducted on thirty rheumatoid arthritis patients attending the Outpatient Clinic of Rheumatology and Rehabilitation department of Ain shams University Hospitals. The patients’ group had been classified into group (1) which included fifteen RA patients associated with sSS diagnosed according to the American–European Consensus Group Classification Criteria and group (2) which included fifteen RA patients not associated with sSS. Ten healthy subjects were included as a control group. Patients were subjected to full history taking, clinical examination, and laboratory detection of CXCL13 level in the plasma and saliva of patients as well as the control groups using ELISA technique. Assessment of disease activity in RA patients was done using the disease activity score (DAS28).ResultsPlasma levels of CXCL13 were significantly higher in RA patients than control group (p<0.001). Plasma levels of CXCL13 were significantly correlated with the RA disease activity (r=0.677, p<0.001) and disease duration (r=0.406, p<0.05), while the salivary levels were higher in those with sSS and correlated with sSS disease duration (r=0.536, p<0.05). A highly significant correlation was found between salivary CXCL13 and severity of sSS (r=0.816, p