The Effect of IFN-γ, Alum and Complete Freund Adjuvant on TNP-KLH Induced Ig.G1, IgE and IgG2aResponses in Mice

[摘要] Adjuvants are considered to play an important role in directing theisotype and amount of antibodies produced upon immunization byconducting the development of either Th-1 or Th-2 cells upon T-cellstimulation. This is based on the different cytokine productionpatterns that were observed afterin vitroresttmulation of T cellsisolated from mice immunized with antigen either adsorbed on alum oremulsified in complete Freund adjuvant (CFA). However, other studiessuggest that primarily the type of antigen determines which isotypesare produced and to what extent. In these studies, however, IgE wasnot determined. Therefore, this study examined whether alum and CFAinfluenced the amount and/or ratio of IgG1, IgE and IgG2aproducedafter TNP-KLH immunization. Similar levels of IgG1, IgE and IgG2aantibodies were found upon immunization with TNP-KLH either adsorbedon alum or emulsified in CFA. Moreover, administration of IFN-γ incombination with TNP-KLH adsorbed on alum did not increase theamount of IgG2aproduced. IFN-γ treatment resulted in an increasedIL-6 and decreased IFN-γ production by spleen cells upon Con Astimulation, whereas it did not change the IL-4 production insimilar conditions. The presented results suggest that uponimmunization with TNP-KLH high IL-4 levels are produced, resultingin an antibody response that is dominated by IgG1, independent of theadjuvant employed. The IL-4 inducing property of TNP-KLH issubstantiated by the finding that repeated immunization of mice withTNP-KI, without adjuvant, increases the serum total IgE level. Thepresented data suggest that the carrier part of TNP-KLHpreferentially results in Th-2 cell activity after which theadjuvant merely enhances the antibody responses generated.

[学科分类] 生理学与病理学