Bovine papillomavirus type 4 L1 gene transfection in a Drosophila S2 cell expression system: absence of L1 protein expression

The development of a bovine papillomavirus (BPV) vaccine is an outstanding challenge. BPV protein L1 gene transfection in the Drosophila melanogaster S2 cell expression system failed to produce L1 protein notwithstanding correct L1 gene insertion. Severe genetic inbalance in the host cell line, including cytogenetic alterations, may account for the lack of protein expression.

O desenvolvimento de uma vacina para papilomavirus bovino (BPV) consiste em grande desafio. A transfecção do gene codificante da proteína L1 de BPV em sistema de células S2 de Drosophila melanogaster não logrou sucesso, apesar da correta inserção da seqüência gênica em vetor apropriado.Graves alterações genéticas na linhagem celular S2, que incluem aberrações cromossômicas, provavelmente estão relacionadas à ausência da expressão da proteína desejada.

Simultaneous presence of bovine papillomavirus and bovine leukemia virus in different bovine tissues: in situ hybridization and cytogenetic analysis

Bovine papillomavirus (BPV) DNA sequences were detected in different tissues, in addition to epithelium. Cytogenetic abnormalities were observed in blood lymphocytes. The presence of more than one virus in a single tissue is a difficult aspect to evaluate, especially when the DNA sequences are detected in tissues that are not specifically targeted by the virus. BPV and bovine leukemia virus (BLV) are clastogenic, causing chromosome aberrations in peripheral blood lymphocytes. In the present study, we investigated the simultaneous presence of DNA sequences of both viruses and the possibility of vertical transmission and compared the types of chromosome aberrations related to viral action. BPV 1, 2, and 4 DNA sequences were found in three females of the herd and in their offspring. BLV DNA sequences were not detected in their progeny. A newborn calf that was negative for BLV infection showed specific chromosome rearrangements possibly related to the effect of infection with BPV.

Análise filogenética de papilomavírus bovino associado com lesões cutâneas em rebanhos do Estado do Paraná / Phylogenetic analysis of bovine papillomavirus associated with skin warts in cattle herds from the state of 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 por cento 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.

Bovine papillomavirus (BPV) infection causes hyperplastic lesions in the cutaneous epithelium of cattle. Six types of BPV were classified in two sub-groups, being correlated to the anatomical regions of the infection and morphologic characteristics of the lesions. The present study was carried out to identify the types of BPV present in skin warts of cattle from the state of Paraná, Brazil. The generic primers FAP59 and FAP64 were used for amplification of a 478 bp fragment of BPV L1 gene in nine cutaneous papilloma samples obtained from six animals in four herds. In all papillomas examined, a product with the expected molecular size was amplified. Phylogenetic analysis of the PCR products identified BPV-2 in three samples, BPV-1 in one, and BPV-6 in five papillomas. BPV-6 was detected in cutaneous papillomas of the teat and in other body parts as well. In one animal, from which more than one sample was collected, a concomitant infection by BPV-1 and BPV-2 was identified. The five positive BPV-6 samples showed a nucleotide identity of 100 percent with the sequence of the reference strain available in GenBank. However, differences among BPV-2 and BPV-1 Brazilian samples and the respective reference sequences deposited in GenBank were observed. Molecular comparison of the two BPV-2 strains identified showed the involvement of two viral variants. This study revealed the diversity of BPV types circulating in the state of Paraná.

Análise filogenética de papilomavírus bovino associado com lesões cutâneas em rebanhos do Estado do Paraná / Phylogenetic analysis of bovine papillomavirus associated with skin warts in cattle herds from the state of 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 por cento 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.

Bovine papillomavirus (BPV) infection causes hyperplastic lesions in the cutaneous epithelium of cattle. Six types of BPV were classified in two sub-groups, being correlated to the anatomical regions of the infection and morphologic characteristics of the lesions. The present study was carried out to identify the types of BPV present in skin warts of cattle from the state of Paraná, Brazil. The generic primers FAP59 and FAP64 were used for amplification of a 478 bp fragment of BPV L1 gene in nine cutaneous papilloma samples obtained from six animals in four herds. In all papillomas examined, a product with the expected molecular size was amplified. Phylogenetic analysis of the PCR products identified BPV-2 in three samples, BPV-1 in one, and BPV-6 in five papillomas. BPV-6 was detected in cutaneous papillomas of the teat and in other body parts as well. In one animal, from which more than one sample was collected, a concomitant infection by BPV-1 and BPV-2 was identified. The five positive BPV-6 samples showed a nucleotide identity of 100 percent with the sequence of the reference strain available in GenBank. However, differences among BPV-2 and BPV-1 Brazilian samples and the respective reference sequences deposited in GenBank were observed. Molecular comparison of the two BPV-2 strains identified showed the involvement of two viral variants. This study revealed the diversity of BPV types circulating in the state of Paraná.

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 percent) urinary bladder. The rate of BPV-2 positive urinary bladders was 50 percent (11/22) for group A, 80 percent (24/30) for group B, and 10 percent (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 percent (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...