Skin lesions in nonulcerated cutaneous leishmaniasis (NUCL) caused by Leishmania (L.) infantum chagasi are characterized by a mononuclear inflammatory infiltrate in the dermis, which is composed mainly of lymphocytes, followed by macrophages, few plasma cells and epithelioid granulomas with mild tissue parasitism. Previous studies have shown that the main population of lymphocytes present in the dermal infiltrate is CD8⁺ T cells, followed by CD4⁺ T cells, which are correlated with IFN‐γ⁺ cells. To improve the knowledge of cellular immune responses in NUCL, skin biopsies were submitted to immunohistochemistry using anti‐ROR‐γt, anti‐IL‐17, anti‐IL‐6, anti‐TGF‐β, and anti‐IL‐23 antibodies to characterize the involvement of Th17 cells in the skin lesions of patients affected by NUCL. ROR‐γt⁺, IL‐17⁺, IL‐6⁺, TGF‐β⁺ and IL‐23⁺ cells were observed in the dermal inflammatory infiltrate of NUCL skin lesions. A positive correlation between CD4⁺ T‐lymphocytes and ROR‐γt⁺ and IL‐17⁺ cells suggests that some of the CD4⁺ T‐lymphocytes in NUCL could be Th17 lymphocytes. Moreover, a positive correlation between ROR‐γt⁺ cells and TGF‐β⁺, IL‐6⁺, IL‐17⁺ and IL‐23⁺ cells could indicate the role of these cytokines in the differentiation and maintenance of Th17 lymphocytes. Our findings improve knowledge of the pathogenesis of this rare and atypical clinical form of leishmaniasis.

中文翻译：

---

中美洲利什曼原虫（L.）infantum chagasi引起的非典型皮肤利什曼病中的Th17淋巴细胞。

由婴儿利什曼原虫（L.） chagasi引起的非溃疡性皮肤利什曼病（NUCL）的皮肤病变的特征是真皮中的单核炎性浸润，主要由淋巴细胞组成，其次是巨噬细胞，少量浆细胞和上皮样肉芽肿，伴有轻度组织寄生虫病。先前的研究表明，真皮浸润液中存在的主要淋巴细胞群是CD8 ⁺ T细胞，其次是CD4 ⁺ T细胞，它们与IFN-γ ^+相关。细胞。为了提高对NUCL中细胞免疫应答的认识，使用抗ROR-γt，抗IL-17，抗IL-6，抗TGF-β和抗IL-23抗体对皮肤活检组织进行了免疫组织化学表征Th17细胞参与受NUCL影响的患者的皮肤病变。在NUCL皮肤病变的皮肤炎性浸润中观察到ROR-γt ⁺，IL-17 ⁺，IL-6 ⁺，TGF-β ⁺和IL-23 ⁺细胞。CD4 ⁺ T淋巴细胞与ROR-γt ⁺和IL-17 ⁺细胞之间呈正相关，表明某些CD4 ⁺NUCL中的T淋巴细胞可能是Th17淋巴细胞。此外，ROR-γt ⁺细胞与TGF-β ⁺，IL-6 ⁺，IL-17 ⁺和IL-23 ⁺细胞之间呈正相关可能表明这些细胞因子在Th17淋巴细胞的分化和维持中的作用。我们的发现提高了对这种罕见且非典型的利什曼病临床形式的发病机理的认识。