First case of nasal transitional carcinoma in a goat infected with Enzootic Nasal Tumor Virus in Belgium

An eleven-year-old, female goat was presented for evaluation of breathing difficulties and epistaxis. Radiographs and computed tomographic (CT) examination of the head revealed the presence of a space-occupying lesion involving the right nasal passage and invading the cranial vault and retrobulbar space. Histologic examination and detection of viral genome from the nasal mass led to the diagnosis of nasal transitional carcinoma with concomitant infection with Enzootic Nasal Tumor Virus (ENTV-2). In this case report, the presence of a nasal transitional carcinoma is described in a goat; a very rare tumor which, to the authors’ knowledge, has not been previously reported in goats. Reverse transcription polymerase chain reaction (RT-PCR) detected the genome of ENTV-2 within the neoplastic tissue, suggesting an infectious etiology.

First case of nasal transitional carcinoma in a goat infected with Enzootic Nasal Tumor Virus in Belgium

An eleven-year-old, female goat was presented for evaluation of breathing difficulties and epistaxis. Radiographs and computed tomographic (CT) examination of the head revealed the presence of a space-occupying lesion involving the right nasal passage and invading the cranial vault and retrobulbar space. Histologic examination and detection of viral genome from the nasal mass led to the diagnosis of nasal transitional carcinoma with concomitant infection with Enzootic Nasal Tumor Virus (ENTV-2). In this case report, the presence of a nasal transitional carcinoma is described in a goat; a very rare tumor which, to the authors’ knowledge, has not been previously reported in goats. Reverse transcription polymerase chain reaction (RT-PCR) detected the genome of ENTV-2 within the neoplastic tissue, suggesting an infectious etiology.

Nasal adenocarcinoma associated with jaagsiekte sheep retrovirus infection in a sheep

Betaretrovirus-induced transmissible respiratory tumors in sheep arise at 2 distinct anatomic locations, either deep in the lung tissue caused by jaagsiekte sheep retrovirus (JSRV) or in the nasal cavity induced by ovine enzootic nasal tumor virus (ENTV-1). JSRV and ENTV-1 are found in many countries worldwide and have a significant economic and animal health impact. Although JSRV is endemic in sheep in the British Isles, ENTV-1 has not been reported. We report herein a nasal adenocarcinoma in a cull 8-y-old Belclare ewe from Ireland. The gross and microscopic features and immunohistochemistry results were consistent with an ENTV-1–associated tumor. However, differential PCR, using primers specific to regions of divergent sequence between the viruses, was performed on different parts of the adenocarcinoma and produced consistent results: positive for JSRV and negative for ENTV-1. An association of JSRV with nasal adenocarcinoma in sheep has not been reported previously, to our knowledge. Our case shows the necessity of using PCR in combination with immunohistochemistry to reach an accurate etiologic diagnosis, which is of importance in countries currently free of ENTV-1.

The U3 and Env Proteins of Jaagsiekte Sheep Retrovirus and Enzootic Nasal Tumor Virus Both Contribute to Tissue Tropism

Jaagsiekte sheep retrovirus (JSRV) and enzootic nasal tumor virus (ENTV) are small-ruminant betaretroviruses that share high nucleotide and amino acid identity, utilize the same cellular receptor, hyaluronoglucosaminidase 2 (Hyal2) for entry, and transform tissues with their envelope (Env) glycoprotein; yet, they target discrete regions of the respiratory tract—the lung and nose, respectively. This distinct tissue selectivity makes them ideal tools with which to study the pathogenesis of betaretroviruses. To uncover the genetic determinants of tropism, we constructed JSRV–ENTV chimeric viruses and produced lentivectors pseudotyped with the Env proteins from JSRV (Jenv) and ENTV (Eenv). Through the transduction and infection of lung and nasal turbinate tissue slices, we observed that Hyal2 expression levels strongly influence ENTV entry, but that the long terminal repeat (LTR) promoters of these viruses are likely responsible for tissue-specificity. Furthermore, we show evidence of ENTV Env expression in chondrocytes within ENTV-infected nasal turbinate tissue, where Hyal2 is highly expressed. Our work suggests that the unique tissue tropism of JSRV and ENTV stems from the combined effort of the envelope glycoprotein-receptor interactions and the LTR and provides new insight into the pathogenesis of ENTV.

A Novel Enzootic Nasal Tumor Virus Circulating in Goats from Southern China

Enzootic nasal tumor virus (ENTV) has two types, ENTV-1 in sheep and ENTV-2 in goats, respectively. In China, the incidence of ENTV-2 related diseases has increased year by year. In this study, we reported an outbreak of ENTV-2 in a commercial goat farm in Qingyuan city, Guangdong province, southern China. A full-length genome of ENTV-2 (designated GDQY2017), with 7479 base pairs, was sequenced. Although GDQY2017 shared the highest nucleotide identity with a Chinese ENTV-2 isolate (ENTV-2CHN4, GenBank accession number KU258873), it possesses distinct genome characteristics undescribed, including a non-continuous 21-nucleotide insertion in the gag gene and a non-continuous 12-nucleotide deletion in the env gene. Notably, most of these indel nucleotide sequences were originated from a Chinese jaagsiekte sheep retrovirus (JSRV) isolate (GenBank accession number DQ838494). In the gag and env genes, GDQY2017 was phylogenetically related to those Chinese ENTV-2 isolates and a Chinese JSRV isolate (DQ838494). For GDQY2017-like viruses, more surveillance work should be made to explain their pathogenicity in goat herds. To our knowledge, this study represents the first to demonstrate the circulating pattern of ENTV-2 in Guangdong province, China, which will help to better understand the epidemiology and genetic diversity of ENTV-2.