Immunohistochemical Assessment of MDA and 8-OHdG Expression in the Skin, Lungs and Kidneys of Lambs Naturally Infected with Sheeppox Virus Confirmed with PCR

This study aimed to assess the role of free radicals in the pathogenesis and progression of sheeppox with the immunohistochemical investigation of MDA and 8-OhdG expressions. The study material comprised of 24 lamb carcasses (suspected of being infected with sheeppox), which were referred to the Pathology Department for routine diagnosis, and 6 healthy lambs used for control purposes. Commercial MDA and 8-OHdG were used for labeling with the avidin-biotin-Peroxidase complex technique by the manufacturer"s instructions. By using PCR the correct-sized amplicon was obtained from eight of the samples. Characteristic pock nodules were detected in the skin, lung, and liver tissues. In histopathological examinations, sheeppox cells and Guarneri bodies, which are quite typical for the diagnosis of the disease, were found in the internal organs. All of the sheeppox-infected cases yielded positive results for MDA and 8-OHdG immunostainings. When compared to the control group, the sheeppoxinfected group displayed statistically higher levels of MDA and 8-OHdG expressions. In conclusion, increased MDA and 8-OHdG expressions in the visceral organs of lambs naturally infected with the sheeppox virus demonstrated that sheeppox is associated with the disruption of the antioxidant/oxidant balance and the occurrence of significant oxidative stress-induced damage to macromolecules such as lipids and the DNA. The positive correlation detected between the severity of the disease and the expression of these biomarkers showed that free radicals are actively involved in the development of pox lesions.