Analysis of C-reactive protein and cytokine profile in sinovial fluids of patients with arthropathies of San Luis city (Argentina)

DAVE MN ; TAMASHIRO H; BLAS R; MUNARRIZ A; GRUPPI A; ELIÇABE RJ; DI GENARO MS

Medellin

Congreso; IMMUNOCOLOMBIA2015 - 11th Congress of the Latin American Association of Immunology - 10o. Congreso de la Asociación Colombiana de Alergia, Asma e Inmunología.; 2015

Latin American Association of Immunology

Rheumatoid arthritis (RA) is a chronic autoimmune disease of unknown etiology, characterized by pain, swelling, and destruction of synovial joints, resulting in functional disability. Joint inflammatory response in RA appears to be due to microvascular changes and an increase in the number of cells or synovial lining hyperplasia. These changes are accompanied by an altered regulation of cytokines, an increase in the number of fibroblasts and excess proliferation of inflammatory cells. Rheumatoid factor (RF) and anti-citrullinated protein antibody (ACPA) positivity in RA is well described and has already been included into the ACR/EULAR 2010 classification criteria. Using both RF and ACPA may be helpful in diagnosis and classification of RA. However, in clinical management of RA, C-reactive protein (CRP) is a commonly ordered test to guide diagnosis of RA and also as indicator of prognosis and the subsequent response to therapy. Spondyloarthritis (SpA) is a group of inflammatory rheumatic diseases comprising ankylosing spondylitis (AS), psoriatic arthritis, reactive arthritis, undifferentiated SpA and SpA associated with inflammatory bowel disease. These interrelated disorders share clinical features, familiar history, strong association with HLAB27 and the absence of RF. SpA can also be characterized as axial or peripheral according to predominant articular features at clinical presentation. Several factors are involved in the pathogenesis of SpA. The HLA-B27 presence, arthritogenic peptides and environmental factors have been associated with these pathologies favoring the deregulation of the immune system and the destruction of joints. Osteoarthritis (OA) is the most prevalent joint disease. It causes pain and disability in a large proportion of the population worldwide. The progression of OA may be caused by abnormal loading of the joint, genetic factors and aging.There is strong evidence that the pro-inflammatory cytokine TNF plays a role in the pathogenesis of RA and SpA. Furthermore, several studies performed with TNF blockers in patients with RA and AS have shown that the majority of patients benefit from this treatment. On the other hand, several studies revealed elevated serum IL-6 levels in patients with RA and SpA as compared with controls, which correlated with disease activity. The IL-10 and TGF-b are immunosuppressive cytokines that have been found elevated in the serum of some patients with arthropathies without distinction between the different clinical forms. Moreover, BAFF (B lymphocyte activating factor of the tumor necrosis factor family) is a vital homeostatic cytokine for B cells that helps regulate both innate and adaptive immune responses. BAFF favors the production of immunoglobulins, especially class-switching to IgA. BAFF have been shown to be increased in patients with several inflammatory rheumatic diseases. Thus, this antibody has been found elevated in both serum and in synovial fluid (SF) of some patients with SpA and in RA patients. A complex, interactive network of cells and cytokines are involved in the pathogenesis of these rheumatic diseases, particularly in the recruitment, activation, and effector functions of immune cells. However, pathogenesis and the role of cytokines in the arthropathies have not yet been fully elucidated and many reports are contradictory. The aim of our study was to analyze CRP and the profile of pro- and anti-inflammatory cytokines to establish distinctive features in patients with arthropathies of San Luis city (Argentina). Moreover, BAFF and IgA levels were also evaluated. SF specimens obtained from 20 patients with RA and 18 with SpA, as pro-inflammatory arthropathies, and 14 patients with OA, as non-inflammatory arthropathy, were used in this study. The RA and SpA patients met the American College of Rheumatology (ACR) and the European Spondyloarthopathy Study Group (ESSG) criteria, respectively. To enroll in the study, patients were subjected to knee effusion of SF requiring drainage. Written informed consent was given by all patients. The principles of Declaration of Helsinki were followed and the study was approved by the Local Ethics Committee. SF was centrifuged (4000 x g, 10 min) to remove cellular debris and stored in aliquots at -20 C until analysis. The TNF, IL-6, IL-10, TGF-b levels were determined with commercial ELISA kits according to the manufacturers? instructions. CRP and IgA were determined by commercial tests of direct agglutination and single radial immunodiffusion, respectively. Differences in the amounts of cytokines in RA and SpA patients were compared to each other and with OA patients by Mann-Whitney test. Differences in the frequencies of CRP detectable level were analyzed by Fisher´s exact test. A p value less than 0.05 was considered as statistically significant. We found higher frequency of SF with CRP positive in RA (19/20, 95%) compared with SpA (8/18, 44%) and OA (3/14, 21%) patients (p