Role of Fas/Fas figand apoptotic pathway of peripheral blood lymphocytes in the development of viral myocarditis

Objective To investigate the role of peripheral blood lymphocyte apoptosis through Fas/ Fas ligand pathway in the development of viral myocarditis. Methods Twenty-five viral myocarditis （VMC） and 25 healthy children were chosen for study. The apoptosis percentage in peripheral blood lymphocytes was quantitatively examined,flow cytometry with Annexin V/PI double parameter was used. And the expressions of Fas and Fasl protein in peripheral blood lymphocytes were analyzed with flow cytometry. Results The percentage of apoptosis in peripheral blood lymphocytes in children with VMC [ （0. 697 6 ± 0. 110 9 ） % ] was significantly higher than that of healthy children [ （ 0. 128 8 ± 0. 106 9 ） % ] （ t = 18. 459, P 〈 0. 001 ）. Moreover, the apoptosis cell percentage showed a significant positive correlation with the serum levels of myocardium enzyme （ creatine kinase-MB, lactate dehydrogenase, creatine kinase, hydroxybutyrate dehydrogenase ） （ r =0. 817 ,P 〈0. 01 ;r =0. 785 ,P 〈0. 01 ;r = 0. 726 ,P 〈0.01 ;r = 0. 712 ,P 〈 0. 01 ）. The expression of Fas and Fasl protein in VMC patients （ 2. 880 4 ± 0. 302 0,4. 449 6 ± 0. 483 6） were higher than those of health children （ 2. 130 0 ±0. 620 0,0. 123 8 ± 0. 038 4 ）, which had significant difference （ t = 17.321, P 〈 0. 001 ; t＇ = 44. 577, P 〈 0. 001 ）. The apoptosis percentage of peripheral blood lymphocytes in children with VMC showed a significant positive correlation with the Fas and Fasl protein expression in peripheral blood lymphocytes（ r = 0. 972, P 〈 0. 01 ; r = 0. 958, P 〈 0. 01 ）. Conclusion Apoptosis percentage of peripheral blood lymphocytes increases among children with VMC, probably because immune response decreased or it is related with the degree of myocardium damaged. Fas and Fasl play an important role in apoptosis of peripheral blood lymphocytes in children with VMC.