Keyhole limpet hemocyanin induced Th1/Th2 imbalance in splenocytes of Balb/C mice / 中国组织工程研究

ABSTRACT

BACKGROUND:Establishing a characteristic.stable and repeatable model of Th1/Th2 imbalance in animals,is the key of studying the mechanism of Th1/Th2 imbalance.OBJECTIVE:To observe the characteristics of Th1/Th2 imbalance in splenocytes derived from Balb/C mice immnnized by keyhole limpet hemocyanin(KLH).DESIGN:A randomized control exploratory experiment.SETTING:Hebei Provincial Forensic Laboratory.Institute of Basic Medicine,Hebei Medical University.MATERLALSThe experiment was carried out in the Hebei Provincial Forensic Laboratory,Institute of Basic Medicine,Hebei Medical University from September 2005 to January 2007.Balb/C mice were adopted in this study.and all the disposals were in accordance with the guidance of animal ethics.METHODS:Balb/C mice were immunized with KLH emulsified in complete Freund's adjuvant(CFA),splenocytes were acquired,and the peak of cytokine secretion was determined in 3 groupsKLH groups of 6.25 mg,kg.12.5 mg,kg and 25 mg/kg.According to the immunizing dose and immunizing frequency.mice were divided into 7 groupsKLH groups of 6.25 mg/kg,12.5 mg/kg and 25 mg/kg,secondary immunity groups of 6.25 mg/kg,12.5 mg/kg and 25 mg/kg,as well as control group.According to the determined levels of IgG1 and IgG2a in blood serum.mice were divided into KLH group of 6.25 mg/kg and control group.MAIN OUTCOME MEASURES:Mice splenocytes supematant was detected with enzyme linked immunosorbent assay (ELISA)for the production of Th1 cytokines interferon (IFN)-γ,interleukin(IL)-2.IL-12 p40 and Th2 cytokines IL-4 and IL-5.The levels of Th1 antibody IgG2a and Th2 antibody IgG1 in blood serum were also detected by ELISA.RESULTS:The spleen derived from KLH-immunized mice appeared hypertrophy,and the number of splenocytes was manifold.Splenocytes restimulated with KLH in vitro produced much more IFN-γ,IL-2,IL-4,IL-5,but not IL-12p40.IL-2 secretion was obviously elevated after incubated for 24 hours and achieved pinnacle at 48 hours;productions of IL-4,IL-5 and IFN-γ were elevated after 24 hours,and increased gradually to 96 hours;IL-12p40 production was very low at every time point.Using different doses of KLH inlmunity once or twice,could all lead to the elevated productions of IL-2,IL-4,IL-5,IFN-γ,and the elevation of IL-4/IFN-γ ratio,but the secondary immunity group of 6.25 mg/kg KLH showed obviously higher levels than other groups(P＜0.01).The level of KLH specific antibody IgG2a and IgG1,especially IgG1 was elevated in blood serum of KLH-immunized mice.CONCLUSION:Balb/C mice immunizad with KLH emulsified in CFA can indce a Th2 predominant imbalance in splenocytes.