Yale University School of Public Health, New Haven, CT 06520-8034, USA.
Eur J Immunol. 2010 Oct;40(10):2816-29. doi: 10.1002/eji.201040384.
Leishmania (Viannia) organisms are the most prevalent etiologic agents of human cutaneous leishmaniasis in the Americas. Nevertheless, our knowledge of the immunological mechanisms exploited by L. (Viannia) organisms remains limited and the mechanisms underlying disease are not well understood. Here, we report the development of a BALB/c mouse model of L. (V.) panamensis infection that is able to reproduce chronic disease, with persistent infection and clinically evident lesions for over 1 year. The immune response of the mouse resembles that found for L. (V.) panamensis-infected patients with chronic and recurrent lesions, presenting a mixed Th1/Th2 response with the presence of TNF-α, IFN-γ, IL-10 and IL-13. Using immunodeficient mice, the critical role for IL-13 and/or IL-4Rα in determining susceptibility to chronic infection was evident. With the induction of healing in the immunodeficient mice, increases in IFN-γ and IL-17 were found, concomitant with parasite control and elimination. Specifically, increases in CD4(+) (but not CD8(+)) T cells producing IFN-γ were observed. These results suggest that IL-13 represents an important target for disease control of L. (V.) panamensis infection. This murine model should be useful to further understand the pathology associated with chronic disease and to develop methods for the treatment and prevention of leishmaniasis caused by L. (Viannia) parasites.
美洲的利什曼原虫(Viannia)生物是人类皮肤利什曼病最常见的病原体。然而,我们对利什曼原虫生物利用的免疫机制的了解仍然有限,疾病的机制也尚不清楚。在这里,我们报告了一种 BALB/c 小鼠感染利什曼原虫(Viannia)panamensis 的模型的发展,该模型能够复制慢性疾病,持续感染并出现临床明显的病变超过 1 年。该小鼠的免疫反应与慢性和复发性病变的利什曼原虫(Viannia)panamensis 感染患者的免疫反应相似,表现为混合 Th1/Th2 反应,同时存在 TNF-α、IFN-γ、IL-10 和 IL-13。使用免疫缺陷小鼠,IL-13 和/或 IL-4Rα 在决定对慢性感染的易感性方面的关键作用是显而易见的。在免疫缺陷小鼠中诱导愈合时,发现 IFN-γ 和 IL-17 增加,同时伴随着寄生虫的控制和消除。具体而言,观察到产生 IFN-γ 的 CD4+(而非 CD8+)T 细胞增加。这些结果表明,IL-13 是控制利什曼原虫(Viannia)panamensis 感染疾病的重要靶点。这种小鼠模型应该有助于进一步了解与慢性疾病相关的病理学,并开发治疗和预防由利什曼原虫(Viannia)寄生虫引起的利什曼病的方法。