Study On The Children’s Long Term Antibody Level And Secretion Of Th1/Th2Cytokines After Immunization With H1N1Influenza Vaccine

Objective: In order to provide a theoretical basis for the new influenza vaccineimmunization strateg, we detect the children’s long-term serum antibody levels afterimmunization with new H1N1influenza vaccine and evaluate the humoral immunepersistence, we detect the cytokine levels of T cell subsets in children with vaccinatedthe new H1N1influenza vaccine and explore the long-term post-vaccination immunememory of T cells.Methods:(1)31healthy volunteer children with vaccinated the new H1N1influenza vaccine wascollected.5ml peripheral blood was drawn from every child. We centrifuged serum after2ml peripheral blood natural clotting and detected the H1N1influenza antibodies byELISA. Set the new H1N1influenza vaccine group and normal cells, and cultured at37℃for50hours in5%CO2incubator. Finally, detect the cytokines from supernatant.(2) Lymphocytes were isolated from3ml peripheral blood. Then adjust the lymphocytesnumber to1×106/ml with10%FBS-RPMI-1640.Results:(1) Four years later, the antibody positive rate was16.13%in31children withvaccinated new H1N1influenza vaccine according to the H1N1-Ab concentrationnormal range in human serum based company provides. The mean antibodyconcentration was70.41ng/L(7.73ng/L～282.91ng/L). The H1N1-Ab data of31samples was tested by Wilcoxon signed rank test(P>0.05), we could not believe that thelevels of H1N1-Ab in children with vaccinated the new H1N1influenza vaccine werehigher than in normal people.(2) The levels of TNF-α of Lymphocyte culture supernatants from31samples weredetectd by flow CBA method. The concentration of TNF-α of Lymphocyte culturesupernatants in normal people was90.41pg/ml,which was higher than in the childrenwith vaccinated the new H1N1influenza vaccine(6.54pg/ml). The data of TNF-αconcentration was tested by Wilcoxon signed rank test, the difference has statisticalsignificance(P<0.05). (3) The levels of IL-10of Lymphocyte culture supernatants from31samples weredetectd by flow CBA method. The concentration of IL-10of cell culture supernatants inthe children with vaccinated the new H1N1influenza vaccine was199.82pg/ml, whichwas lower than in normal people(1704.56pg/ml). The data of IL-10concentration wastested by Wilcoxon signed rank test, the difference has statistical significance(P<0.05).(4) The levels of INF-γ and TNF-α of Lymphocyte culture supernatants from16samples(odd number) were detectd by ELISA method. The mean concentration ofIFN-γ of cell culture supernatants in the children with vaccinated the new H1N1influenza vaccine and in the normal people were respectively176.22pg/ml,185.71pg/ml, the difference has no statistical significance(P>0.05). The meanconcentration of TNF-α of Lymphocyte culture supernatants in the children withvaccinated the new H1N1influenza vaccine and in the normal people were respectively152.29pg/ml,173.34pg/ml, the difference has no statistical significance(P>0.05).(5) The levels of IL-4and IL-10of Lymphocyte culture supernatants from16samples(odd number) were detectd by ELISA method. The mean concentration of IL-4of cell culture supernatants in the children with vaccinated the new H1N1influenzavaccine and in the normal people were respectively224.03pg/ml,225.95pg/ml, thedifference has statistical significance(P<0.05). The mean concentration of IL-10ofLymphocyte culture supernatants in the children with vaccinated the new H1N1influenza vaccine and in the normal people were respectively180.68pg/ml,405.31pg/ml, the difference has statistical significance(P<0.05).Conclusion:(1) Four years later,the antibody positive rate was16.13%in31children withvaccinated new H1N1influenza vaccine, the mean antibody concentration was70.41ng/L. So the children with vaccinated new H1N1influenza vaccine has notstrong humoral immunity after four years.(2) Four years later, the cytokine levels of Th1/Th2in children with vaccinated the new H1N1influenza vaccine were lower than in the normal people, which suggested that the newH1N1influenza vaccine has not strong specific immune memory function and welllong-term of immune memory.