Phylogenetic position of an uncharacterized Brazilian strain of bovine papillomavirus in the genus Xipapillomavirus based on sequencing of the L1 open reading frame

The use of PCR assays with degenerate primers has suggested the existence of numerous as yet uncharacterized bovine papillomaviruses (BPV). Despite the endemic nature of BPV infections, the identification of BPV types in Brazilian cattle is still only sporadic. However, in a recent analysis of a partial segment of the L1 gene, we observed notable diversity among the BPV types detected. The aim of this study was to determine the phylogenetic position of the previously identified wild strain BPV/BR-UEL2 detected in the state of Paraná in Brazil. Since previous analysis of the partial L1 sequence had shown that this strain was most closely related to BPV type 4, genus-specific primers were designed. Phylogenetic analysis using complete L1 ORF sequences revealed that BPV/BR-UEL2 was related to BPV types classified in the genus Xipapillomavirus and shared the highest L1 nucleotide sequence similarity with BPV type 4 (78%). This finding suggests that BPV/BR-UEL2 should be classified as a potential new type of BPV in the genus Xipapillomavirus

Análise filogenética de papilomavírus bovino associado com lesões cutâneas em rebanhos do Estado do Paraná

A infecção pelo papilomavírus bovino (BPV) causa lesões hiperplásicas no epitélio cutâneo dos animais. De acordo com a localização e as características morfológicas das lesões, os seis tipos de BPV são classificados em dois sub-grupos. O objetivo desse trabalho foi identificar os tipos de BPV presentes em lesões cutâneas em bovinos de rebanhos do Estado do Paraná. Os primers degenerados FAP59 e FAP64 foram utilizados para a amplificação de um fragmento com 478 pb do gene L1 do BPV bovino em nove amostras de papilomas cutâneos obtidos de seis animais provenientes de quatro rebanhos bovinos do Estado. Em todas as amostras foi possível a amplificação de um produto com a massa molecular esperada. Por meio da análise filogenética das seqüências dos amplicons foi possível identificar o BPV-2 em três amostras, o BPV-1 em uma e o BPV-6 em cinco amostras de papilomas. O BPV-6 foi encontrado tanto em papilomas localizados no teto quanto em outras partes do corpo. Em um dos animais, do qual foram colhidas mais de uma amostra, foi detectada infecção concomitante do BPV-1 com o BPV-2. As cinco amostras positivas para o BPV-6 apresentaram 100% de identidade de nucleotídeos com a amostra padrão disponível no GenBank. No entanto, foram identificadas diferenças entre as amostras do BPV-2 e BPV-1 e aquelas depositadas neste banco de dados. Esse estudo demonstrou a diversidade de tipos do BPV circulantes em rebanhos do Estado do Paraná

Multiple bovine papillomavirus infections associated with cutaneous papillomatosis in brazilian cattle herds

Cutaneous papillomatosis is a pathological condition commonly found in cattle and is characterized by the presence of benign proliferative tumors caused by bovine papillomavirus (BPV) infection. While multiple infections with human papillomavirus (HPV) are common in healthy and immunodeficient humans, studies with the aim of identifying mixed infections are still sporadic in veterinary medicine. The aim of this study is to describe the occurrence of multiple BPV infections in cattle affected by cutaneous papillomatosis. Fifteen skin warts were collected from at least two diverse anatomical regions of six bovines with papillomatosis belonging to three cattle herds from the Paraná state in Brazil. The BPV types present in the skin wart samples were determined by a PCR assay performed with the FAP primer pair for partial L1 gene amplification followed by direct sequencing or by cloning and sequencing of the inserts. Sequence analysis of the obtained amplicons allowed the identification of four characterized BPV types (BPV-1, -2, -6, and -8) and three previously described putative new BPV types (BPV/BR-UEL3, BPV/BR-UEL4, and BPV/BR-UEL5). Double infections were identified in four (A, B, D, and E) of the six animals included in this study. In this work, the strategy adopted to evaluate skin warts from diverse anatomical sites of the same animal allowed the identification of multiple infections with two or three different BPV types. The analysis of four animals belonging to a single cattle herd also showed the presence of six different viral types. These results clearly suggest that both multiple papillomaviral infection and a high viral diversity can be as frequent in cattle as in human beings.<br>A papilomatose cutânea é comumente observada nos rebanhos bovinos e caracterizada pela presença de tumores proliferativos benignos causados pela infecção pelo papilomavírus bovino (BPV). Enquanto a infecção múltipla pelo papilomavírus humano (HPV) é um achado comum tanto em seres humanos saudáveis quanto em pacientes com imunodeficiência, na medicina veterinária esses relatos ainda são escassos. O objetivo desse estudo foi descrever a ocorrência de infecções múltiplas pelo BPV em rebanhos afetados pela papilomatose cutânea. Quinze papilomas foram obtidos, de pelo menos duas regiões anatômicas diferentes, de seis bovinos com papilomatose e provenientes de três rebanhos de corte localizados no estado do Paraná, Brasil. Os tipos virais presentes nas lesões foram identificados por PCR, utilizando o par de oligonucleotídeos iniciadores FAP, seguidos de sequenciamento direto ou clonagem e novo sequenciamento dos insertos. A análise das sequências obtidas permitiu a identificação do BPV-1, -2, -6 e -8, além de supostos novos tipos (BPV/BR-UEL3, BPV/BR-UEL4, e BPV/BR-UEL5), descritos anteriormente. Infecções por dois tipos diferentes de BPV foram identificadas em quatro animais (A, B, D e E) dos seis incluídos nesse estudo. A estratégia adotada neste estudo permitiu a identificação de infecção múltipla por dois ou três diferentes tipos virais do BPV no mesmo animal. Além disso, a avaliação de quatro animais de um mesmo rebanho demonstrou a presença de seis tipos virais circulantes. Esses resultados sugerem que tanto as infecções múltiplas quanto a grande diversidade viral podem ser frequentes nos bovinos, assim como o observado nos humanos. O reconhecimento da multiplicidade e complexidade das infecções pelo BPV pode colaborar para o entendimento dos aspectos epidemiológicos, clínicos e imunológicos da papilomatose cutânea nos rebanhos bovinos

Bovine papillomavirus type 2 detection in the urinary bladder of cattle with chronic enzootic haematuria

The bovine papillomavirus type 2 (BPV-2) involvement in the aetiology of chronic enzootic haematuria associated to bracken fern ingestion has been suggested for a long time. However, a few reports have shown the presence of the BPV-2 in urinary bladder tumors of cattle. The aim of this study was to investigate the presence of the BPV-2 infection in the urinary bladder of cattle with chronic enzootic haematuria in Brazilian cattle herds. Sixty-two urinary bladders were collected from adult cattle in beef herds from the north region of the state of Paraná, Brazil. According to clinical and pathological finds the specimens were distributed in three groups: the group A was constituted by 22 urinary bladders with macroscopic lesions collected at necropsy of cattle with clinical signs of chronic enzootic haematuria; the group B by 30 urinary bladders with macroscopic lesions collected in a slaughterhouse of cows coming from bracken fern-endemic geographical region; and the group C (control) by 10 urinary bladders without macroscopic lesions collected from asymptomatic cattle in a bracken fern-free geographical region. By a semi-nested polymerase chain reaction (PCR) assay, with an internal control, a fragment of the BPV-2 L1 gene with 386 bp length was amplified in 36 (58%) urinary bladder. The rate of BPV-2 positive urinary bladders was 50% (11/22) for group A, 80% (24/30) for group B, and 10% (1/10) for group C (control). The rate of the positive results found in groups A and B that included urinary bladder samples with macroscopic lesions was 67% (35/52) and the detection of the BPV-2 in both groups was significantly higher (P < 0.05) than in the control group. RFLP with Rsa I and Hae III enzymes evaluated the specificity of the BPV-2 amplicons. The PCR internal control that amplified a 626 bp fragment of the ND5 gene of the bovine mitochondrial genome was amplified in all analyzed samples and excluded false-negatives or invalid results in the semi-nested PCR. These results suggest the BPV-2 involvement in the chronic enzootic haematuria aetiology and open the perspective of the development of new strategies for the control of this disease that is the major cause of economical losses in beef herds from many Brazilian geographical regions