实验感染肝片吸虫的水牛体液免疫反应的研究

为研究水牛抗肝片吸虫感染的免疫反应机制，选择８头雄性去势水牛经粪便检查和Ｄｏｔ－ＥＬＩＳＡ检测确认无肝片吸虫感染。经２周适应性饲养后，随机分成感染组（ｎ＝５）和对照组（ｎ＝３）。感染组水牛每天每头经口感染６０个囊蚴，连续２０天，共感染１２００个囊蚴。每周颈静脉采血，测定Ｔ、Ｂ淋巴细胞比例、血清总蛋白含量和组分比例以及抗体（ＩｇＧ）水平。结果表明：感染组水牛从感染肝片吸虫后第２周开始，Ｔ淋巴细胞比例显著下降而Ｂ淋巴细胞比例显著上升，１６周后，Ｔ、Ｂ淋巴细胞比例恢复到与对照水牛相当水平。感染组水牛血清总蛋白（ＴＰ）、α一球蛋白、β－球蛋白与以对照组相比均无显著性变化，而白蛋白（％）从感染第２周开始下降，以后一直在低于对照组的水平波动；感染组水牛的γ一球蛋白（％）高于或显著高于对照组。血清抗肝片吸虫体从感染后第４周开始显著升高，１９周达到峰值，２２周时回落到与对照组相近的水平。结果提示：血清ＩｇＧ水平升高是水牛抗肝片吸虫感染的重要机制。

STUDY ON HUMORAL IMMUNE RESPONSES IN WATER BUFFALOES INFECTED EXPER IMENTALLY WITH FASCIOLA HEPATICA

Eight male testiclectomy water buffaloes had no fasiolosis by fecal examination and DotELISA were used for the experiment.After adaptive feeding of two weeks,water buffaloes were randomly divided into infection group (n=5) and F.hepatica metacercariae per day and 1200 metacercariae during 20 days.Blood was collected from jugular vein to measure T,Blymphocyte ratio,serum protein concentration and ratio,and antibody(IgG) level weekly.The results showed that Tlymphocytes(%) decreased significantly during the 2nd to 16th week of postinfection,but Blymphocytes(%) increased markedly in the meantime,then T and B lymphocytes had no apparent difference as compared with that of control group.Serum protein concentration,globulin(%) and globulin(%) of infection group had no significant difference as compared with that of control group,but albumin level started to decrease in the 2nd week of postinfection and fluctuated at low levels.Globulin of infection group fluctuated at higher level than that of control group.Serum antibody markedly rose in the 4th week of postinfection and peaked in the 18th week,then dropped to the level which appeared no significant difference as compared with that of control group in the 22nd week.