Análise molecular de papilomavírus canino identificado em cães naturalmente infectados no estado de Sergipe - Brasil

Abstract

The papillomatosis is an infectious disease caused by papillomaviruses which belongs to the Papillomaviridae family. In dogs, Canis familiaris papillomavirus (CPV) species is the causative agent of the disease and it has so far twenty identified types. These viruses can lead to benign neoplastic lesions of the skin and mucosal epithelium that are exophytic and endophytic papilloma and pigmented plaques which may occur progression to carcinoma squamous cell (SCCs) cancer. The pathogenicity of the virus related to the types, subtypes and variants can influence deafferents lesions on the animal. Thus, there is a need to identify and characterize the existing virus to a better understanding of the disease and adoptions of both preventive measures as treatment. In this study, the general objective is to analyze the genetic diversity of canine papillomavirus present in infected dogs in the state of Sergipe - Brazil. We used diagnostic strategies for the identification of canine papillomavirus; wherein the histopathology was used to the characterization of the lesion as papilloma and the PCR with electrophoresis for confirm the viral DNA, then sequencing performed for subsequent genotyping of samples and bioinformatics tools was used for analysis of the nucleotide and amino acid sequences of the L1 gene. As a result, eighteen samples of possible papillomatous lesions were collected and nine samples had the presence of CPV DNA with oral and cutaneous exophytic lesions confirmed by histopathology. It was possible observe in one sample the presence of oral SCCs. The Canine papillomavirus type 1 (CPV1) was identified in nine samples of this study. Eight samples were CPV1 variants with 100% identity with the already described variants and one sample was identified as a new CPV1 variant having a difference of 0.8% when compared with the reference sequence of the CPV1 L1 gene and a difference of 0.2% with the existing CPV1 variant. The mutations of the variants and the change in stability of the protein structure were analyzed and it was observed that the V204A mutation of the new variant of isolate eight is highly destabilizing with alteration of protein function. This study corroborates the characterization of CPV1 as the main cause of oral papillomatosis in dogs, observing the genetic variability of CPV1 with variants of different pathogenic potentials, with a putative new variant associated with cancer with a mutation that can destabilize the L1 protein structure of CPV1 altering its function.