Araujo Flores Gabriela Venicia, Sandoval Pacheco Carmen Maria, Tomokane Thaise Yumie, Sosa Ochoa Wilfredo Humberto, Silveira Fernando Tobias, Zúniga Concepción, Pereira Corbett Carlos Eduardo, Soares Rodrigo Pedro Pinto, Passero Luiz Felipe Domingues, Laurenti Marcia Dalastra
Universidade de São Paulo, Faculdade de Medicina, Laboratório de Patologia de Moléstias Infecciosas, São Paulo, São Paulo, Brazil.
Universidad Nacional Autónoma de Honduras, Instituto de Investigaciones en Microbiologia, Tegucigalpa, Honduras.
Rev Inst Med Trop Sao Paulo. 2025 Apr 4;67:e21. doi: 10.1590/S1678-9946202567021. eCollection 2025.
In Honduras, Leishmania (Leishmania) infantum chagasi, the etiological agent of visceral leishmaniasis (VL), is responsible for non-ulcerated cutaneous leishmaniasis (NUCL). We characterized NUCL and VL Honduran strains to understand intraspecies infectivity. Based on in-vitro assays, we aimed to elucidate certain host-parasite interactions in VL and NUCL isolates through a hamster model. To assess the capacity of these strains to infect peritoneal macrophages, we exposed them to promastigotes from NUCL and VL patients at varying temperatures and time intervals (32, 34, and 36 °C; 24 and 48 h) and infection-index (II) was determined. No significant differences were observed over time for dermotropic strains; however, a higher II was noted at lower temperatures (32 and 34 °C). Interestingly, only the VL strain exhibited a higher II at elevated temperatures (34 and 36 °C) at 48 h. Low levels of oxygen and nitrogen-derived metabolites were detected in both NUCL and VL strains. For in-vivo assays, hamsters were infected subcutaneously (SC) and intraperitoneally (IP) with 107-promastigotes from NUCL and VL patients. After 90 days of infection, parasite-load and histopathological changes were assessed from spleen samples. Regardless of the administration route, no substantial differences were observed in the histopathological features between NUCL and VL strains. In conclusion, lower temperatures may favor parasite infection for NUCL strains, mirroring conditions found in the skin. This contrasts with the VL strain, which demonstrated a superior II at higher temperatures, a condition normally found in the viscera. Our data also indicate that M. auratus is susceptible to Honduran L. (L.) infantum chagasi strains, circumventing the skin barrier by IP or SC injection.
在洪都拉斯，内脏利什曼病（VL）的病原体婴儿利什曼原虫（Leishmania (Leishmania) infantum chagasi）可导致非溃疡性皮肤利什曼病（NUCL）。我们对洪都拉斯的NUCL和VL菌株进行了特征分析，以了解种内感染性。基于体外试验，我们旨在通过仓鼠模型阐明VL和NUCL分离株中某些宿主-寄生虫相互作用。为了评估这些菌株感染腹膜巨噬细胞的能力，我们在不同温度和时间间隔（32、34和36°C；24和48小时）将它们暴露于NUCL和VL患者的前鞭毛体，并测定感染指数（II）。趋皮性菌株随时间未观察到显著差异；然而，在较低温度（32和34°C）下观察到较高的II。有趣的是，仅VL菌株在48小时时在较高温度（34和36°C）下表现出较高的II。在NUCL和VL菌株中均检测到低水平的氧和氮衍生代谢物。对于体内试验，仓鼠皮下（SC）和腹腔内（IP）接种来自NUCL和VL患者的107个前鞭毛体。感染90天后，从脾脏样本评估寄生虫载量和组织病理学变化。无论给药途径如何，NUCL和VL菌株之间的组织病理学特征均未观察到实质性差异。总之，较低温度可能有利于NUCL菌株的寄生虫感染，这反映了皮肤中的情况。这与VL菌株形成对比，VL菌株在较高温度下表现出更高的II，这是内脏中通常存在的情况。我们的数据还表明，金黄仓鼠对洪都拉斯婴儿利什曼原虫菌株易感，通过IP或SC注射可绕过皮肤屏障。
