Laboratório Interdisciplinar de Pesquisas Médicas, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil.
Instituto de Medicina Tropical do Rio Grande do Norte, Universidade Federal do Rio Grande do Norte, RN, Brazil.
J Immunol Res. 2021 Mar 29;2021:6657785. doi: 10.1155/2021/6657785. eCollection 2021.
Cytokines and growth factors involved in the tissue inflammatory process influence the outcome of infection. Insulin-like growth factor (IGF-I) constitutively present in the skin may participate in the inflammatory process and parasite-host interaction. Previous work has shown that preincubation of () with recombinant IGF-I induces accelerated lesion development. However, in human cutaneous leishmaniasis (CL) pathogenesis, it is more relevant to the persistent inflammatory process than progressive parasite proliferation. In this context, we aimed to investigate whether IGF-I was present in the CL lesions and if this factor may influence the lesions' development acting on parasite growth and/or on the inflammatory/healing process. . Fifty-one CL patients' skin lesion samples from endemic area of () infection were submitted to histopathological analysis and searched for and IGF-I expression by immunohistochemistry.
In human CL lesions, IGF-I was observed preferentially in the late lesion (more than 90 days), and the percentage of positive area for IGF-I was positively correlated with duration of illness ( = 0.42, < 0.05). IGF-I was highly expressed in the inflammatory infiltrate of CL lesions from patients evolving with good response to therapy (2.8% ± 2.1%; median = 2.1%; = 18) than poor responders (1.3% ± 1.1%; median: 1.05%; = 6; < 0.05).
It is the first time that IGF-I was detected in lesions of infectious cutaneous disease, specifically in American tegumentary leishmaniasis. IGF-I was related to chronicity and good response to treatment. We may relate this finding to the efficient anti-inflammatory response and the known action of IGF-I in wound repair. The present data highlight the importance of searching nonspecific factors besides adaptive immune elements in the study of leishmaniasis' pathogenesis.
参与组织炎症过程的细胞因子和生长因子会影响感染的结果。胰岛素样生长因子（IGF-I）在皮肤中持续存在，可能参与炎症过程和寄生虫-宿主相互作用。先前的工作表明，（）与重组 IGF-I 孵育可诱导病变加速发展。然而，在人类皮肤利什曼病（CL）发病机制中，与寄生虫增殖相比，持续的炎症过程更为相关。在这种情况下，我们旨在研究 IGF-I 是否存在于 CL 病变中，以及该因子是否通过作用于寄生虫生长和/或炎症/愈合过程而影响病变的发展。方法：对来自（）感染流行地区的 51 例 CL 患者皮肤病变样本进行组织病理学分析，并通过免疫组织化学法检测和 IGF-I 的表达。结果：在人类 CL 病变中，IGF-I 主要在晚期病变（超过 90 天）中观察到，IGF-I 阳性区域的百分比与疾病持续时间呈正相关（=0.42，<0.05）。IGF-I 在对治疗反应良好的 CL 病变的炎症浸润中高表达（2.8%±2.1%；中位数=2.1%；=18），而在反应不佳的患者中低表达（1.3%±1.1%；中位数：1.05%；=6；<0.05）。结论：这是首次在感染性皮肤病的病变中检测到 IGF-I，特别是在美洲皮肤利什曼病中。IGF-I 与慢性和对治疗的良好反应有关。我们可以将这一发现与有效的抗炎反应和 IGF-I 在伤口修复中的已知作用联系起来。本研究数据强调了在研究利什曼病发病机制时，除适应性免疫成分外，还需要寻找非特异性因素的重要性。
