摘要
目的:探讨卡介苗(BCG)对大鼠结核感染及CD4+CD8+双阳(DP)T细胞的影响。方法:60只PPD皮试阴性SD大鼠随机分成(1)卡介苗免疫(BCG)组(、2)BCG免疫后结核分枝杆菌(Mtb)攻击(BCG-TB)组、(3)Mtb攻击后不化疗(TB)组。BCG组、BCG-TB组于观察开始接种BCG。BCG-TB组、TB组于3个月末接受Mtb攻击。比较全部大鼠接种Mtb后的死亡率;实验开始和其后3、4、5、6、8个月末检测外周血中T细胞亚群。结果:BCG组、BCG-TB组无死亡;TB组感染后5个月内死亡率45%(9/20)。TB组死亡率高于BCG组和BCG-TB组,P<0.01。实验开始时3个组组间对应参数比较差异均无显著性(P>0.05);3个月末BCG组、BCG-TB组之间各对应参数比较差异均无显著性(P>0.05);BCG组和BCG-TB组第3个月末与接种前比较,CD8+、DP升高,且显著高于TB组(Mtb干预之前),P<0.01或P<0.05。BCG组DP细胞于接种BCG后第6个月后开始回落,但仍显著高于接种前;BCG-TB组于Mtb攻击1个月后CD8+、DP继续升高,观察的第8个月CD8+、DP回落,但仍显著高于BCG接种前;TB组Mtb攻击后1个月末CD8+、DP有升高但低于BCG组和BCG-TB组,同时伴有CD3+、CD4+降低,差异均有显著性,P<0.05或P<0.01,此后维持在相近水平。Mtb攻击2个月末BCG-TB组DP高于BCG组和TB组,P<0.05或P<0.01。Mtb攻击5个月后3个组间DP差异无显著性(P>0.05)。结论:BCG预防接种可保护Mtb感染宿主免于发病和死亡,增强抗结核保护性细胞免疫力表现之一为DP细胞升高,DP细胞是抗结核保护性免疫相关T细胞。DP细胞的形成与CD4+SP细胞上CD8+抗原表达有关。
Objective： To investigate the relationship between the rat CD4^＋ CD8^＋ double positive （DP）T lymphocytes and tuberculosis. Methods：Sixty SD rats with PPD skin-test negative were divided into three groups at random：①BCG group, ② BCG-TB group [infected with Mycobacteriurn tuberculosis（Mtb） after vaccine with BCG 3 months],③ TB（Tuberculosis） group. Mortality of each group was measured. CD3^＋ , CD4^＋ , CD8^＋ and DP T lymphocytes of peripheral blood of rats were measured at the beginning of experiment and at the end of 3rd,4th,5th,6th,8th month during the experiment. Results： （1）Mortality of TB group was 45% （9/20 rats） and was higher than that of other two groups （0/40）;P〈0.01. （2） In the beginning, comparison every corresponding data of T subset of three groups, there was no statistically significantdifference,P〉0. 05. CD8^＋ and DP T lymphocyte subset from peripheral blood of BCG group and BCG-TB group rats showed to go up statistically significantly in first 3 months of experiment,and were higher than that of TB group before infected by Mtb,P〈0.05 or P〈0.01,but there was no statistically significant difference between BCG group and BCG-TB group,P〉0.05. （3）BCG-TB group had no symptom although infected by Mtb, peripheral CD8^＋ and DP T lymphocytes of rats showed to go up higher after infection with Mtb 1 month than that of the same group before infection with Mtb, while ratio of CD4/CD8（without CD4^＋） decreased lower than that of the same group before TB infection,P〈0. 05 or P〈0. 01. （4）In TB group, ratio of CD4/CD8 of tuberculosis rats decreased after infected by Mtb 1 month,while CD8^＋ ,DP T lymphocytes went up, company CD3^＋ , CD4^＋ decreased,P〈0.05 and P〈0.01. Conclusion：（1）BCG vaccination can protect the host so that be free from suffering from tuberculosis or from die when that were infected by Mtb. It showed that BCG vaccination induce strengthen immunity. DP T cell is the protective immune effect cell against tuberculosis. （2）DP T cell increase is due to expression of CD8^＋ antigen on CD4^＋ simple positive T cells.
出处
《实用临床医学（江西）》
CAS
2006年第9期3-6,12,F0003,共6页
Practical Clinical Medicine
基金
江西省社会发展攻关重点基金(2004)
作者简介
雷建平（1948-），男，本科，教授，主任医师，主要从事结核病基因诊断和免疫治疗。
