[颗粒溶素/白细胞介素-12重组耻垢分枝杆菌在结核分枝杆菌感染小鼠模型中的治疗作用]

[Therapeutic effects of granulysin/interleukin-12 recombinant M. smegmatis in a murine model of M. tuberculosis infection].

作者信息

Yang Chun, Wang Yu-wei, Yi Zheng-jun, He Yong-lin, Li Na, Xu Lei, Zhang Li, Zhu Dao-yin

机构信息

Department of Immunology and Microbiology, Chongqing University of Medical Sciences, Chongqing 400016, China.

出版信息

Zhonghua Jie He He Hu Xi Za Zhi. 2007 Feb;30(2):133-7.

PMID:17445478

Abstract

OBJECTIVE

To study the effects and mechanisms of recombinant Mycobacterium smegmatis (M. smegmatis) encoding human granulysin and murine interleukin-12 (IL-12) on murine M. tuberculosis infection.

METHODS

Balb/c mice infected with M. tuberculosis were treated with normal saline, M. smegmatis, pZM03, recombinant M. smegmatis respectively. The numbers of viable bacteria in the lung and the spleen were counted. The levels of IL-12, IgG(2a) in serum and interferon-gamma (IFN-gamma) released from spleen lymphocytes stimulated with purified protein derivative (PPD) were detected with enzyme linked immunosorbent assay (ELISA). The expression of granulysin in tissue was detected with immunohistochemistry. Lungs and spleens were prepared for pathological analysis.

RESULTS

The recombinant M. smegmatis group [(4.57 +/- 0.28) in lung, (3.47 +/- 0.25) in spleen] showed significantly reduced number of colony forming units (log CFU/g) compared with the control [(5.77 +/- 0.12) in lung, (4.66 +/- 0.18) in spleen], M. smegmatis [(5.62 +/- 0.14) in lung, (4.65 +/- 0.26) in spleen] and pZM03 [(5.04 +/- 0.22) in lung, (4.25 +/- 0.48) in spleen] group. The expression of granulysin in tissue, and increased level of IL-12 and IgG(2a) in serum were found in recombinant M. smegmatis group. IFN-gamma released from spleen lymphocytes stimulated with PPD in recombinant M. smegmatis group and pZM03 group was higher than that of other groups, but the difference between recombinant M. smegmatis group and pZM03 group was not significant. The pathological changes in lungs of the recombinant M. smegmatis group were localized, while those in the control group were extensive. Significant pathological changes were not found in the spleens of all groups.

CONCLUSION

The recombinant M. smegmatis had immunotherapeutic effects, which were associated with a switch to Th1 response and the antibacterial activity of granulysin.

摘要

目的

研究编码人颗粒溶素和小鼠白细胞介素-12（IL-12）的重组耻垢分枝杆菌对小鼠结核分枝杆菌感染的影响及其机制。

方法

将感染结核分枝杆菌的Balb/c小鼠分别用生理盐水、耻垢分枝杆菌、pZM03、重组耻垢分枝杆菌进行处理。计数肺和脾中的活菌数。采用酶联免疫吸附测定（ELISA）检测血清中IL-12、IgG(2a)水平以及纯化蛋白衍生物（PPD）刺激脾淋巴细胞释放的干扰素-γ（IFN-γ）水平。用免疫组织化学法检测组织中颗粒溶素的表达。制备肺和脾进行病理分析。

结果

重组耻垢分枝杆菌组[肺中(4.57±0.28)，脾中(3.47±0.25)]与对照组[肺中(5.77±0.12)，脾中(4.66±0.18)]、耻垢分枝杆菌组[肺中(5.62±0.14)，脾中(4.65±0.26)]和pZM03组[肺中(5.04±0.22)，脾中(4.25±0.48)]相比，菌落形成单位（log CFU/g）数量显著减少。重组耻垢分枝杆菌组组织中颗粒溶素表达增加，血清中IL-12和IgG(2a)水平升高。重组耻垢分枝杆菌组和pZM03组中PPD刺激脾淋巴细胞释放的IFN-γ高于其他组，但重组耻垢分枝杆菌组与pZM03组之间差异不显著。重组耻垢分枝杆菌组肺中的病理变化局限，而对照组广泛。所有组的脾中均未发现明显病理变化。