High Genotypic Diversity, Putative New Types and Intra-Genotype Variants of Bovine Papillomavirus in Northeast Brazil

Genetic Evaluation of Bovine Papillomavirus Types Associated with Teat Papillomatosis in Polish Dairy Cattle with the Report of a New Putative Type

Teat papillomatosis is reported to be one of the factors causing mastitis and milk losses in dairy cattle. Little is known about bovine papillomavirus (BPV) circulation in the European cattle population, and no reports can yet be found about its prevalence in Polish herds. In this study, 177 BPV-like lesions were collected from teats of 109 slaughtered cows. BPV was identified in 39 of the examined animals, using PCR amplification and Sanger dideoxy sequencing. In total, 10 BPV types were isolated, among which the most common were infections caused by types 8 and 7. Macroscopically, "rice-grain" type lesions dominated (76%) and were mainly found on one teat (57.4%). The diversity of BPV types causing teat papillomatosis in Polish cows seems to be large, with nine already known types isolated and a new putative type found. The spread of new types among the worldwide cattle population can be seen for the first time, as type 25 and so called isolates BPV42 and BPV43 were found in the European cattle population.

Diagnosis and phylogenetic analysis of bovine papillomaviruses in cattle papillomatosis cases by different methods

Papillomaviruses, known as epitheliotropic, cause proliferation in the skin, mucosa, and different visceral organs. In this study, it was aimed to diagnose bovine papillomavirus (BPV) by using different methods in the lesion taken from twenty cattle with papillomas in different areas of the body and to reveal its molecular characterization. In our study, molecular, immunohistochemistry, and transmission electron microscopy (TEM) methods were used for virus identification. Additionally, sequencing analysis was used to ascertain the phylogenetic relationship between the obtained field strains and other isolates submitted to GenBank. Histopathological analyses of the collected samples were done in addition to diagnostic procedures. Intranuclear virus particles were detected when the papillomas were investigated with TEM. In PCR analyses using degenerate and type-specific primer sets, the presence of BPV nucleic acid was determined in 70% (14/20) and 90% (18/20) of the samples, respectively. No virus could be detected in PCR applications using MY 09/11 degenerate primer sets. Twenty animals of different ages, races, and genders included in the study by random sampling method from different herds were divided into 4 groups according to the body regions where the lesions were located. Sequence analysis was performed on a sample from each group that showed strong positivity in the PCR technique using FAP 59/64 degenerate primer set and type-specific primer set. Sequence analyses were performed using FAP 59/64 degenerate primers of amplicons for phylogenetic research. In these analyses, three of the isolated strains were identified as BPV-1, which is in the Deltapapillomavirus 4 genus, and one as BPV-2. As a result of the study, it was concluded that molecular and phylogenetic studies using type-specific primers are more beneficial in order to fully reveal the etiology of papillomatosis in cattle and it would be correct to determine BPV types before prophylactic (vaccine, etc.) applications.

Molecular typing of bovine papillomaviruses in Costa Rica

Bovine papillomaviruses are related to cause fibroepithelial proliferations in the skin and mucosae and are associated with economic loss mainly related to poor body condition and reduced milk production. This study aimed to investigate the presence and types of bovine papillomaviruses (BPVs) in cattle sampled in different areas of Costa Rica using molecular techniques. A descriptive study with a non-probability convenience sampling was carried out. A total of 99 papillomatous lesions were collected from 63 animals in 32 farms, and analyzed by polymerase chain reaction, rolling circle amplification (RCA), sequencing, and restriction enzymes digestion. Seven bovine papillomavirus types (BPV1, BPV2, BPV4, BPV6, BPV7, BPV10, BPV11) and two putative novel viral variants (BPV-CR1 and BPV-CR2) were identified for the first time in Costa Rica. BPV6 was the most frequently detected virus in lesions (31.2%), followed by BPV2 (25%) and BPV1 (25%). BPV1 and BPV2 were the most widely distributed in the Country. Coinfections were recorded in two animals (BPV1 / BPV2 and BPV4 / BPV6). Restriction analyses allowed differentiating BPV1 from BPV2, BPV4, and BPV7, but failed to identify BPV6, BPV10, and BPV11. Results suggest that a great PVs diversity is harbored by bovines in Costa Rica and indicate the need for further investigations aimed to uncover PV diversity at the full genomic level.

Metatranscriptomics Analysis Reveals Diverse Viral RNA in Cutaneous Papillomatous Lesions of Cattle

Bovine papillomavirus (BPV) is associated with bovine papillomatosis, a disease that forms benign warts in epithelial tissues, as well as malignant lesions. Previous studies have detected a co-infection between BPV and other viruses, making it likely that these co-infections could influence disease progression. Therefore, this study aimed to identify and annotate viral genes in cutaneous papillomatous lesions of cattle. Sequences were obtained from the GEO database, and an RNA-seq computational pipeline was used to analyze 3 libraries from bovine papillomatous lesions. In total, 25 viral families were identified, including Poxviridae, Retroviridae, and Herpesviridae. All libraries shared similarities in the viruses and genes found. The viral genes shared similarities with BPV genes, especially for functions as virion entry pathway, malignant progression by apoptosis suppression and immune system control. Therefore, this study presents relevant data extending the current knowledge regarding the viral microbiome in BPV lesions and how other viruses could affect this disease.

The Development of Novel Primer Sets to Specifically Amplify Each of the Five Different Deltapapillomaviruses That Cause Neoplasia after Cross-Species Infection

Bovine papillomavirus (BPV) types 1 and 2 are recognized as the main cause of equine sarcoids. However, some studies report that up to a quarter of these tumors do not contain detectible BPV1 or BPV2 DNA. The absence of detectible BPV1 or BPV2 in these sarcoids suggests the possible involvement of other papillomavirus types. Currently, five deltapapillomaviruses are recognized to cause mesenchymal neoplasia after cross-species infection. In addition to BPV1 and BPV2, BPV13 has been associated with equine sarcoids in Brazil, BPV14 has been associated with feline sarcoids, and Ovis aries papillomavirus 2 caused a sarcoid-like lesion in a pig. To investigate the cause of equine sarcoids, PCR primers were developed to specifically amplify each of the five different deltapapillomaviruses that have been associated with mesenchymal neoplasia. The specificity of these primers was confirmed using samples of formalin-fixed tissue known to contain each PV type. These primers allow rapid and sensitive detection of deltapapillomavirus DNA in equine sarcoids. As studies have revealed marked regional variability in the cause of equine sarcoids, these primers will be useful to determine the predominant PV type causing sarcoids in a region. Additionally, there is a single report describing mixed infections by BPV1 and BPV2 in equine sarcoids. The specific primer sets are expected to enable more sensitive detection of mixed infections in equine sarcoids. Determining the cause of equine sarcoids is important as vaccines are developed to prevent these common malignant neoplasms.