三氯乙烯对致敏豚鼠脾淋巴细胞毒性的体外实验研究

目的　探索三氯乙烯(TCE)诱导过敏性皮炎发生的免疫学机制。方法　采用豚鼠最大值法建立TCE致敏的豚鼠动物模型,应用四唑蓝(MTT)法测定TCE及其活性代谢产物对体外培养的致敏及非致敏豚鼠脾淋巴细胞的细胞毒性和促增殖活性。结果　阴性对照组动物脾淋巴细胞与TCE (+S9)共孵育3 d后,细胞存活率(63.4%±8.4%)明显低于TCE (-S9)处理组(77.0%±7.2%),差异有统计学意义(P<0.01);TCE致敏组动物淋巴细胞与TCE (+S9)共孵育后细胞存活率(83.0%±3.4%)明显高于TCE (-S9)处理组(75.9%±7.9%),差异有统计学意义(P<0.01);TCE (+S9)孵育的淋巴细胞存活率致敏组(83.0%±3.4%)与阴性对照组(63.4%±8.4%)的差异有统计学意义(P<0.05),而TCE(-S9)孵育的淋巴细胞存活率此两组(75.9%±7.9%、77.0%±7.2%)的差异无统计学意义(P>0.05)。结论　TCE经代谢活化后对正常淋巴细胞的毒性增强,促进致敏淋巴细胞的增殖活性,TCE的代谢产物可能作为半抗原诱导了抗原特异性淋巴细胞的增殖转化。

Immunological mechanism in development of allergic dermatitis in guinea pig induced by trichloroethylene in vitro

OBJECTIVE: To investigate the immunological mechanism of allergic dermatitis induced by trichloroethylene (TCE). METHODS: The guinea pig model of TCE-induced allergic dermatitis was established by Guinea pig Maximization Test. The effects of TCE and its metabolites on splenic lymphocytes of TCE-sensitized and non-sensitized guinea pig were detected by MTT assay. RESULTS: For TCE-sensitized guinea pig, the survival rate of lymphocytes cultured with TCE (+S9) was significantly higher than that cultured with TCE (-S9) (83.0% +/- 3.4% vs 75.9% +/- 7.9%, P < 0.01), while, for normal animals, the survival rate of lymphocytes cultured with TCE (+S9) was significantly lower than that cultured with TCE (-S9) (63.4% +/- 8.4% vs 77.0% +/- 7.2%, P < 0.01). The survival rate of lymphocytes cultured with TCE (+S9) in TCE-sensitized animals was higher than that in normal animals (83.0% +/- 3.4% vs 63.4% +/- 8.4%, P < 0.05), but no statistically significant difference was found for TCE (-S9) (75.9% +/- 7.9% vs 77.0% +/- 7.2%, P > 0.05). CONCLUSION: Cytotoxicity of TCE to normal lymphocytes and proliferation of sensitized lymphocytes were enhanced by metabolic activation. The metabolites of TCE may act as effective immune hapten to stimulate the proliferation of hapten-specific lymphocytes in TCE-sensitized animals.