Parasitology Research, cilt.124, sa.11, 2025 (SCI-Expanded, Scopus)
Leishmaniasis is a vector-borne disease endemic in more than 99 countries and manifests primarily as cutaneous, mucocutaneous, or visceral forms. This study aimed to assess the impact of Leishmania RNA virus 2 (LRV2) on immune responses and disease pathology in mice infected with Leishmania tropica. BALB/c mice were inoculated subcutaneously in the right hind footpad with L. tropica either lacking or carrying LRV2 (LRV2– and LRV2 + groups, respectively) and monitored for 24 weeks. Footpad and liver tissues were collected post-sacrifice, and parasite presence was determined using microscopy, culture, and molecular methods. Biomarkers of inflammation (IL-6, TNF-α, and TGF-β1), oxidative stress (iNOS and eNOS), and apoptosis (Caspase 3) were analyzed by immunohistochemistry and qPCR. Leukocyte infiltration was observed in footpad lesions of both LRV2– and LRV2 + groups; however, lesion sizes did not differ significantly between them. In footpad tissues, TNF-α, TGF-β1, eNOS, and Caspase 3 expression levels were significantly higher in both experimental groups compared to controls. In liver tissues, IL-6 and eNOS expression was significantly elevated in both experimental groups relative to controls, while TNF-α expression was notably higher in the LRV2 + group. Furthermore, both footpad and liver tissues from LRV2 + mice showed increased eNOS and iNOS expression compared to LRV2– mice. Overall, these findings indicate that the presence of LRV2 does not significantly influence inflammatory cytokine production or apoptosis in footpad and liver tissues, but it markedly enhances oxidative stress in both.