Purpose

Leishmania major-infected BALB/c mice display strong susceptibility to the infection due to the induction of Th2 response. The aim of this study was to assess the effects of naloxone on virulence of L. major in BALB/c mice and the ensued cellular immune response.

Methods

The effects of injection of a single dose of naloxone in the footpad of L. major-infected BALB/c mice were investigated by evaluating the lesion sizes, the parasite burden, cell proliferation, secreted cytokines (IFN-γ, IL-4, IL-10 and IL-12) and their genes expressions due to naloxone treatment while the untreated mice were used as a control.

Results

Significantly lower lesion sizes and less parasite burden were measured in the treated mice. Significantly decreased productions of IFN-γ, IL-12, IL-4, and IL-10 were also observed in the treated mice at week 4 post-infection while the production IL-10 remained significantly hindered till 8 weeks post-infection.

Conclusion

Our data indicated that although the treatment of L. major-infected BALB/c mice with a single dose of naloxone was unable to improve the cellular immune response, it led to lower virulence, confirmed by significantly reduced lesions and parasite load.

中文翻译：

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纳洛酮降低毒力并改变感染大利什曼原虫的 BALB/c 小鼠的细胞免疫反应

目的

由于诱导了 Th2 反应，主要利什曼原虫感染的 BALB/c 小鼠对感染表现出很强的易感性。本研究的目的是评估纳洛酮对BALB/c 小鼠中L. Major 毒力的影响以及随后的细胞免疫反应。

方法

纳洛酮的足垫的单剂量的注入的影响硕大利什曼原虫感染的BALB / c小鼠，通过评价损伤尺寸，寄生虫负担，细胞增殖，分泌的细胞因子（IFN-γ，IL-4，IL调查-10 和 IL-12) 及其基因表达由于纳洛酮处理而未处理的小鼠用作对照。

结果

在治疗的小鼠中测量到显着较小的病灶大小和较少的寄生虫负荷。在感染后第 4 周，在治疗的小鼠中也观察到 IFN-γ、IL-12、IL-4 和 IL-10 的产生显着减少，而 IL-10 的产生在感染后 8 周仍显着受阻。

结论

我们的数据表明，虽然用单剂量的纳洛酮治疗受L. Major 感染的 BALB/c 小鼠无法改善细胞免疫反应，但它导致毒力降低，这通过显着减少的病变和寄生虫负荷来证实。