BCG对哮喘小鼠气道炎症反应的影响

目的：探讨卡介苗(BCG)对卯蛋白(OVA)致敏小鼠肺组织中T细胞的在体调节及其对气道炎症的作用。方法：将30只BALB／c小鼠分为3组，第1组吸入雾化的OVA(1次／(1．20min／次，连续10d)，建立致敏模型。第2组(对照)吸入雾化的生理盐水(时间和次数同第1组)；第3组(治疗组)于致敏前10d及14d，各皮内注射BCG 1次，致敏后6d吸入雾化的纯蛋白衍生物(PPD)。用SABC免疫组化法，检测肺组织中CD4^ 、CD8^ 及IFN—γ^ 细胞的变化，以及肺组织和支气管肺泡灌洗液(BALF)中炎性细咆的变化。结果：OVA致敏组小鼠肺组织中CD4^ T细胞增加，CD8^ T细胞无明显变化，主要表现为IFN—γ^-／CD4^ T细胞数的增加，IFN—γ^ ／CD4^ 细胞的比例降低。BCG治疗后，肺组织中CD4^ T细胞减少，CD8^ T细胞数大量增加；IFN—γ^ ／CD4^ 细胞的比例明显增大；BALF中炎性细胞数减少。结论：BCG可在体上调Th1细胞，减轻实验性哮喘动物气道的炎症反应。

The effect of BCG on airway inflammatory reaction of experimental asthma mice

AIM: To explore in-vivo regulation of T cells in pulmonary tissues of ovalbumin(OVA)-sensitized mice by BCG and its effect on airway inflammatory reaction. METHODS: Thirty BALB/c mice (male and female, 6 to 8 weeks of age) were divided into 3 groups. For the mice of first group, aerosol OVA was inhaled daily for 20 minutes once for 10 days running, so as to establish a OVA-sensitized mouse model. In the mice of second group, aerosol normal solution was inhaled according to the time and frequency of the first group. In the third group, the mice were intradermally injected with BCG of 0.04 to 0.06 mg on 10 and 14 days before OVA sensitization, respectively, and then aerosol purified protein derivative (PPD) was inhaled to the mice on 6 days after OVA sensitization. The changes in the number of CD4(+), CD8(+) and IFN-gamma(+) T cells in the inflammatory tissues and changes in the inflammatory cells in the inflammatory tissues and broncho-alveolar lavage fluid (BALF) were detected by SABC immuno-histochemical staining. RESULTS: The number of CD4(+) T cells significantly increased in the pulmonary tissues of OVA-sensitized mice, which mainly was the increased number of CD4(+)/IFN-gamma(-) T cells, While the number of CD8(+) T cells had no notable variation, thus the ratio of CD4(+)/IFN-gamma(+) T cells descended. After BCG treatment, the number of CD8(+) T cells markedly increased, so the ratio of CD4(+)/ IFN-gamma(+) T cells variously rose, whereas the number of inflammatory cells decreased in BALF. CONCLUSION: BCG can upregulate the number of Th1 cells and lighten the airway inflammatory reaction of experimental asthma mice.