Ishikawa Larissa Lumi Watanabe, da Rosa Larissa Camargo, França Thais Graziela Donegá, Peres Raphael Sanches, Chiuso-Minicucci Fernanda, Zorzella-Pezavento Sofia Fernanda Gonçalves, Sartori Alexandrina
Departamento de Microbiologia e Imunologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), 18618-970 Botucatu, SP, Brazil.
Clin Dev Immunol. 2012;2012:673186. doi: 10.1155/2012/673186. Epub 2012 Apr 10.
Cellular immunity is critical for protection against tuberculosis, but its integrity is compromised during undernutrition. The present study was designed to evaluate if the attenuated mycobacterium BCG is a safe vaccine for undernourished individuals. An experimental model of undernutrition was established by subjecting BALB/c mice to dietary restriction. These animals received 70% of the amount of food consumed by the healthy control group and exhibited physiological alterations compatible with malnutrition, including body weight loss, reduced levels of triglycerides and glucose, and reduced lymphocyte numbers. Undernourished mice were immunized with BCG, and the mycobacterial loads in lymph nodes, spleen, liver, lungs, and thymus were determined. A much higher proportion of undernourished mice exhibited bacterial dissemination to the lymph nodes, spleen and liver. In addition, only undernourished animals had bacteria in the lungs and thymus. Concomitant with higher mycobacterial loads and more widespread BCG dissemination in undernourished mice, production of TNF-α, IFN-γ, and IL-10 was also diminished in these mice. Taken together, these results indicate that BCG infection is more severe in undernourished mice. Whether a similar phenomenon exists in undernourished children or not remains to be thoroughly investigated.
细胞免疫对于预防结核病至关重要，但在营养不良期间其完整性会受到损害。本研究旨在评估减毒分枝杆菌卡介苗（BCG）对营养不良个体是否为一种安全的疫苗。通过对BALB/c小鼠进行饮食限制建立了营养不良的实验模型。这些动物摄入的食物量为健康对照组的70%，并表现出与营养不良相符的生理改变，包括体重减轻、甘油三酯和葡萄糖水平降低以及淋巴细胞数量减少。对营养不良的小鼠接种卡介苗，并测定其淋巴结、脾脏、肝脏、肺和胸腺中的分枝杆菌载量。营养不良的小鼠中，有更高比例的小鼠出现细菌扩散至淋巴结、脾脏和肝脏。此外，只有营养不良的动物肺部和胸腺中有细菌。与营养不良小鼠中更高的分枝杆菌载量和更广泛的卡介苗扩散相伴的是，这些小鼠中肿瘤坏死因子-α（TNF-α）、干扰素-γ（IFN-γ）和白细胞介素-10（IL-10）的产生也减少。综上所述，这些结果表明卡介苗感染在营养不良的小鼠中更为严重。营养不良的儿童是否存在类似现象仍有待深入研究。
