A Soluble Form CTLA-4 In Sera Of Patients With Bronchial Asthma

Objective To investigate the role of soluble form of cytotoxic lymphocyte associated antigen-4 CTLA-4(sCTLA-4) in the pathogenesis of atopic asthma. Methods 62 patients with atopic asthma and 28 nonatopic normal volunteers were studied. The concentrations of sCTLA-4 and Th2 dominate cytokines IL-4 and IL-5 were determined using ELISA. By inhaling the methylacetylcholine to observe the airway hyperrespponsiveness, with cytometry to calculate the aomunts of blood cells and the amounts of different kind of blood cells on the blood smear stained by Diff-Quik. Pulmonary function , partial pressure of oxygen (PaO2) and partial pressure of carbon dioxide(PaCO2) were performed before the study. Analysising the difference of sCTLA-4 between patients of asthma and normal volunteer, and the relationship between sCTLA-4 and above items. Results The serum soluble CTLA-4 concentrations of patients with atopic asthma(19.7 2.5 g/L) is significantly higher than the healthy control group (1.8 0.8 g/L, P <0.01) furthermore,the concentrations of sCTLA-4 is increased when patient's condition is serious, the serum soluble CTLA-4 concentrations in the asthmatics statistically correlated negative with PD20-FEV1 (r =-0.489,P <0.01) , percentage of predicted forced expiratory volume in one second (r =-0.495,P <0.01) , percentage of predicted peak expiratory flow (r =-0.514,F <0.01) . the concentration of sCTLA-4 corrected positive with PaCO2 (r =0.481,P <0.01), the amounts of blood cells (r =0.316,P <0.05) and the amounts of lymphcytes (r =0.576,P <0.01) . Our results also showed that the concentration of sCTLA-4 was significantly related to serum concentrations of interleukin-4(r =0.786,P <0.01) and interleukin-5(r =0.684, P <0.01). Conclusions Theserum-soluble CTLA-4 protein is a important factors that influence the severity of asthma The high levels of CTLA-4 in sera from patients with asthma may play a protective role via interference with CD28-B7 interaction; Our findings also suggest that the serum soluble CTLA-4 level may be involved in Th2-dominant inflammation.