Autoantibodies to adenozine deaminase as marker of immunological disorders in systemic lupus erythematosus

Abstract

Objectives. The autoantibodies to various enzymes are often found out in sera of systemic lupus erythematosus (SLE) patients, but clinical value of such antibodies often is not understood. Purpose. The purpose of work was to study the of antibodies generation to the basic enzyme of purine metabolism – Adenozine Deaminase (ADA) in SLE and to reveal the relationship of studied antibodies with clinical and laboratory features of pathological process. Methods. 30 healthy persons have been included in our study and 71 SLE patients (66 women and 5 men) with various clinical signs (44 persons had 1st degree of disease activity, 27 persons – 2nd degree of pathological process activity). 18 women had habitual noncarrying of pregnancy (HNP) in anamnesis. Antibodies of IgG class to ADA (anti- ADA) determined by technique of indirect ELISA developed by us with the use of immobilized form of ADA as an antigenic matrix. β2-glicoprotein-I-dependent antiphospholipids (aPhL) of IgG and IgМ classes were determined using commercial „Anti- Phospholipid Screen IgG/IgM” test set (Orgentec Diagnostica). Results. At admission an anti-ADA was revealed in 36,6%, aPhL of IgG class – in 45,1%, and aPhL of IgМ class – in 23 (32,4%) SLE patients. It has been noted that IgG- aPhL were found out in anti-ADA-positive patients more often and in higher antibody titer, than in anti-ADA-negative SLE patients (χ2 =6,4; р <0,02). Development of cytopenic syndrome was noted reliable more often in SLE patients with associated presence of IgGaPhL and an anti-ADA in comparison with patients who has not the combinations of these antibodies in blood (χ2 = 3,9; р <0,05). The increased levels of anti-ADA were revealed in 11 of 18 women with HNP, and the combination of anti-ADA and aPhL (9/18) was found out more often than isolated anti-ADA (2/18, χ2 =6,5; р <0,02) or isolated aPhL (3/18, χ2 =4,5; р <0,05). Conclusion. Taking into account the imbalance of immunoregulatory functions in SLE, the further studying of autoantibodies to ADA generation seems to be very promising. Presence of HNP in anamnesis is the evidence of necessity of careful biochemical monitoring of aPhL and anti-ADA in women for the prevention of abortus fetus and administration of adequate therapy.