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1.
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2.
Although the cause of bovine ocular squamous cell carcinoma (BOSCC) is attributed to viruses in addition to cofactors (eg, UV light), to our knowledge, the final causative agent has not been described. Bovine papilloma virus (BPV)-like particles were detected in approximately 33% of various putative precursor lesions of BOSCC. In contrast, it was reported that, using BPV-specific antibodies, it was not possible to detect viral antigens in BOSCC. Fourteen established BOSCC and 9 BOSCC-derived cell lines were examined for BPV DNA. Probes of all 6 known BPV types were used in various hybridization assays. Neither Southern blot analysis, under high and low stringency conditions, nor in situ hybridization resulted in detection of BPV DNA. Papilloma viruses were not observed in electron microscopic studies. Results exclude direct association between BOSCC and BPV types 1 to 6, or as yet unknown closely related BPV types. However, BPV may contribute to induction of precursor lesions or events leading to carcinogenic transformation, without being relevant for maintenance of the tumor.  相似文献   

3.
Bovine papillomavirus (BPV) is perhaps the most extensively studied animal papillomavirus. In cattle BPVs induce benign tumours of cutaneous or mucosal epithelia, called papillomas or warts. Cattle papillomas are benign tumours and generally regress without eliciting any serious clinical problems in the host, but occasionally persist and provide the focus for malignant transformation to squamous cell carcinoma, as in the case of cancer of the urinary bladder and cancer of the upper alimentary canal. BPV is the only papillomavirus that jumps species: the virus also infects equids, and gives rise to fibroblastic tumours called sarcoids. Sarcoids very rarely regress, more often they persist and can be locally aggressive. These tumours are the most common dermatological tumour of equids worldwide. The purpose of this review is to discuss the biology of BPV, the biology of bovine tumours and equine sarcoids, and present the current understanding of BPV in tumour pathogenesis in its natural host, cattle, and in its heterologous host, equids. Finally, the use of anti-BPV vaccines as a therapy for equine sarcoids will be discussed. Only limited information on the clinical or pathological aspects of either bovine or equine tumours will be provided as this subject has been extensively addressed previously.  相似文献   

4.
Nineteen cutaneous and mucocutaneous papillomas, as well as 29 oral and 25 non-oral squamous cell carcinomas of dogs were analyzed immunohistologically for the presence of papillomavirus (PV)-antigens. Canine oral papillomavirus (COPV)-DNA was detected in formalin-fixed, paraffin-embedded tissues by polymerase chain reaction (PCR) and non-radioactive in situ hybridization (ISH). Furthermore, the expression of the tumor suppressor protein p53 was investigated. PV-antigens were detectable in more than 50% of the oral and cutaneous papillomas, while no PV-antigens could be demonstrated in venereal papillomas. One squamous cell carcinoma was PV-antigen positive. Only two cutaneous papillomas of the head showed a strong p53-specific immunostaining, while overexpressed p53 was detectable in approximately 35% of all squamous cell carcinomas. It was possible to amplify fragments of the E6, E7 and L1 gene by polymerase chain reaction (PCR) from five of eight oral and from five of eight cutaneous papillomas as well as from three oral squamous cell carcinomas. Nine of 10 papillomas showed a strong nucleus-associated hybridization signal typical for COPV-DNA. In three squamous cell carcinomas COPV-DNA was located in nests of the epithelial tumor cells surrounding ‘horn pearls' or disseminated in the carcinoma tissue. These observations support the view that COPV may also induce non-oral papillomas in the dog and confirm the opinion that a progression of viral papillomas into carcinomas in dogs may occur.  相似文献   

5.
Reasons for performing study: Sarcoids are nonmetastasising, yet locally aggressive skin tumours that constitute the most frequent neoplasm in equids. Infection by bovine papillomaviruses types 1 and 2 (BPV‐1, BPV‐2) has been recognised as major causative factor in sarcoid pathogenesis, but a possible correlation of intralesional virus load with disease severity has not been established thus far. Hypothesis: Given the pathogenic role of BPV‐1 and BPV‐2 in sarcoid disease, we suggest that intralesional viral DNA concentration may reflect the degree of affection. Methods: Severity of disease was addressed by recording the tumour growth kinetics, lesion number and tumour type for 37 sarcoid‐bearing horses and one donkey. Viral load was estimated via quantitative real‐time PCR (qPCR) of the E2, E5, L1 and L2 genes from the BPV‐1/‐2 genome for one randomly selected lesion per horse and correlated with disease severity. Results: Quantitative PCR against E2 identified viral DNA concentrations ranging from 0–556 copies/tumour cell. Of 16 horses affected by quiescent, slowly growing single tumours or multiple mild‐type lesions, 15 showed a viral load up to 1.4 copies per cell. In stark contrast, all equids (22/22) bearing rapidly growing and/or multiple aggressive sarcoids had a viral load between 3 and 569 copies per cell. Consistent results were obtained with qPCR against E5, L1 and L2. Conclusions: While tumours of the same clinical type carried variable virus load, confirming that viral titre does not determine clinical appearance, we identified a highly significant correlation between intralesional viral load and disease severity. Potential relevance: The rapid determination of BPV viral load will give a reliable marker for disease severity and may also be considered when establishing a therapeutic strategy.  相似文献   

6.
Bovine papilloma virus (BPV) was extracted from five cattle each affected with only one of five morphologically distinct lesion types. When inoculated into experimental calves either by scarification or intradermal injection, the BPV extracts produced lesions macroscopically and microscopically similar to those from which individual extracts were made. Fetal bovine cells, transformed in vitro with BPV, failed to produce fibromas, fibropapillomas or papillomas when inoculated into experimental calves. When calves inoculated with virus or BPV transformed cells were challenged with the five original BPV extracts, a differential immunity was demonstrated, while control calves were susceptible to all extracts. Post mortem examination revealed the presence of upper alimentary tract papillomas in three of eight calves forming one group. These results suggest that different strains of BVP, causing morphologically separable lesion types, exist. There may be additional BPV variants causing fibropapillomas of the teat and anogenital regions of cattle. The inoculation of BPV transformed fetal bovine cells conferred a relative immunity to later challenge with some but not all BPV extracts.  相似文献   

7.
Squamous cell carcinoma (SCC) is the most common malignant cutaneous and oral neoplasm of cats. Papillomavirus (PV) DNA has been identified in a proportion of feline Bowenoid in situ carcinomas (BISCs), cutaneous SCCs and a single oral SCC, but its exact role in the pathogenesis remains unknown. In humans, it has been suggested that ultraviolet (UV) light and human PV (HPV) may act as cofactors in cutaneous SCC carcinogenesis. Little is known about the influence of UV light on PV prevalence in feline cutaneous lesions, including actinic keratosis (AK). Additionally, PV prevalence in noncutaneous feline lesions, including oral SCC, is largely not known. This study aimed to determine the presence of PV in 84 cats with premalignant and invasive SCC from cutaneous and noncutaneous sites using polymerase chain reaction and to investigate an association with UV light. Papillomaviral DNA was amplified from two of 12 cases of AK, seven of 22 BISCs, nine of 39 cutaneous SCCs and two of 35 non‐cutaneous SCCs. Of the PV DNA sequenced, 50% was most similar to HPV of the genus Betapapillomavirus, while the other 50% was most similar to Felis domesticus PV type 2. Exposure to UV was not associated with an increase in PV for cutaneous SCC. The results of this study suggest that in the cat, HPV DNA may be detectible within a higher percentage of squamous lesions than previously demonstrated, UV exposure may not be a confounder for PV presence, and noncutaneous lesions may have a low prevalence of PV.  相似文献   

8.
Bovine papillomaviruses (BPV) are DNA oncogenic viruses inducing hyperplastic benign lesions of both cutaneous and mucosal epithelia in cattle. Ten (BPV 1-10) different viral genotypes have been characterised so far. BPV 1-10 are all strictly species-specific but BPV 1/2 may also infect equids inducing fibroblastic tumours. These benign lesions generally regress but may also occasionally persist, leading to a high risk of evolving into cancer, particularly in the presence of environmental carcinogenic co-factors. Among these, bracken fern is the most extensively studied. The synergism between immunosuppressants and carcinogenic principles from bracken fern and the virus has been experimentally demonstrated for both urinary bladder and alimentary canal cancer in cows whose diets were based on this plant. BPV associated tumours have veterinary and agricultural relevance in their own right, although they have also been studied as a relevant model of Human papillomavirus (HPV). Recent insights into BPV biology have paved the way to new fields of speculation on the role of these viruses in neoplastic transformation of cells other than epithelial ones. This review will briefly summarise BPV genome organization, will describe in greater detail the functions of viral oncoproteins, the interaction between the virus and co-carcinogens in tumour development; relevant aspects of immunity and vaccines will also be discussed.  相似文献   

9.
Evidence for papillomaviruses in ocular lesions in cattle   总被引：3，自引：0，他引：3  
Negatively stained preparations of various ocular lesions, generally considered to be precursors to bovine ocular squamous cell carcinoma, were subjected to electron microscopic examination for viruses. Lesions examined included five conjunctival plaques, an acanthotic lesion from an eyelid, 15 conjunctival papillomas, two papillomas of the eyelid and two keratinised elongated proliferative lesions of the eyelid (cutaneous horns). Eight lesions contained particles that resembled papillomaviruses. These consisted of a conjunctival plaque, five conjunctival papillomas, a papilloma of the eyelid and one of the samples of cutaneous horn. The particles were present in small numbers and were found only after prolonged search. The finding of these particles suggests that papillomavirus may be involved in the aetiology of bovine ocular squamous cell carcinoma.  相似文献   

10.
Over a period of two years four ornamental koi carp (Cyprinus carpio) of one variety in a mixed population of 16 were affected with papillomas of the head and body. In one fish there was a transition of these tumours into a squamous cell carcinoma in the region of the head and posterior gill space, with deep invasion of the underlying bone. One of the fish recovered completely after the sloughing of the papillomas. In view of the progressive nature of the lesions, the condition was presumed to be due to an infectious agent, but transmission electron microscopy failed to reveal any virus particles.  相似文献   

11.
A spectrum of proliferative cutaneous lesions occurred in 12 dogs at the injection site of live canine oral papillomavirus (COP) vaccine, suggesting a viral etiology for the masses. Lesions included epidermal hyperplasia, epidermal cysts, squamous papilloma, basal cell epithelioma, and squamous cell carcinoma. Peroxidase-antiperoxidase staining of tumor sections revealed nuclei which stained for group-specific papillomavirus antigen in five of 12 masses. Electron microscopic examination of tumor sections did not reveal virions. In transmission studies, macerated tumor tissue did not produce oral papillomas on the scarified mucosa of puppies; this procedure did protect the puppies from development of lesions when challenged with infectious papilloma material. These findings are evidence that COP can induce hyperplastic and neoplastic lesions in sites other than oral, pharyngeal, and ocular mucosa.  相似文献   

12.
Background – Canine squamous cell carcinomas (SCCs) most frequently develop on the ventral abdomen and are thought to be caused by ultraviolet (UV) light. Papillomaviruses (PVs) have been associated with cutaneous SCCs in multiple species, including dogs. Hypothesis – That PVs act as cofactors in canine UV‐induced SCCs. Animals – The study was performed on skin from the ventrum of 60 dogs. These samples included 20 SCCs, 20 haemangiosarcomas and 20 samples of clinically normal skin. Two canine viral plaques were included as positive controls for PV. Methods – PCR was used to amplify PV DNA from all samples. Primers used included two sets of consensus primers and two sets of primers that were designed specifically to amplify PV DNA sequences detected in the viral plaques. Results – The MY09/11 consensus primers amplified PV DNA from both viral plaques. One plaque contained a DNA sequence (CfPV‐JM) that had been previously reported from a dog with multiple cutaneous SCCs. The other plaque contained a previously unreported PV DNA sequence. No PV DNA was amplified by either consensus primer from any of the ventrum skin samples. Primers designed specifically to amplify the CfPV‐JM sequence amplified DNA from one SCC, but no other sample. No PV DNA was amplified using the other specific PCR primer set. Conclusions and clinical importance – These results do not support a significant role for PVs in SCC development from the ventrum of dogs. However, they contribute another PV sequence to the list of PVs that have been associated with viral plaque development in dogs.  相似文献   

13.
Out of a sample of 200 rumens from sheep slaughtered in Edinburgh, papillomas were found in 25. They occurred as fibro-papillomas, mostly along the pillar of muscle between the dorsal and ventral rumen, and were often multiple. No inclusion bodies were seen in the lesions or papilloma virus particles on electron microscopy. Homogenisation of papillomatous tissue followed by various methods of purification did not yield identifiable virus particles, and viral DNA was not detected. Immunoperoxidase staining showed a very small number of positive cells at or on the surface of 6 out of 10 lesions examined. Thus, it seems probable that virus particles are not found in large numbers in the rumen papillomas of sheep, unlike the situation in ovine skin warts, but are present in a few epithelial cells which are rapidly shed from the surface of the mucous membrane.  相似文献   

14.
In equids, bovine papillomaviruses of type 1 (BPV-1) and less frequently type 2 induce common, locally aggressive skin tumours termed sarcoids. Whereas BPV infection in cattle usually involves the epidermis and is productive in this skin layer, infection in equids is currently thought to be abortive, with virus solely residing as multiple episomes in dermal fibroblasts. Based on recent observations that do not agree with this assumption, we hypothesised that BPV also infects equid epidermis and is active in this skin layer. To test this hypothesis, we conducted a proof-of-principle study on eight distinct sarcoids. Presence of viral DNA was addressed by qualitative and quantitative BPV-1 PCR from microdissected sarcoid epidermis, and by subsequent amplicon sequencing. Viral activity was assessed by screening sarcoid epidermis for BPV-1 protein expression using immunohistochemistry (IHC) or immunofluorescence (IF). Virus-free equine skin served as negative control throughout the assays. BPV-1 DNA was demonstrated in all sarcoid epidermis samples, with viral DNA loads ranging between 2 and 195 copies/cell. Identical BPV-1 E5 genes were identified in epidermis and dermis of each of two sarcoids, yet different E5 variants were found in individual lesions. IHC/IF revealed the presence of E5 and E7 protein in sarcoid epidermis, and L1 capsomers in the squamous layer of one lesion. These findings indicate that BPV infection also involves the epidermis, where it may occasionally be productive.  相似文献   

15.
增生性病变与癌前病变的研究对于肿瘤的早期诊断、早期防治以及认识肿瘤在形态学上的发生发展过程均有重要意义。国内外医学对这一方面的研究日益重视,但在兽医科学领域中,尚未引起注意。本文作者应用病理组织学方法,对家畜和一部分野生动物的食管、胃和大小肠等消化系统组织共1,037例进行了研究,检出了一批增生性病变和癌前病变,它们是:上皮的单纯性增生、上皮的乳头状增生、粘膜白斑、慢性溃疡、上皮的不典型增生、乳头状瘤和腺瘤性息肉。研究中并发现上皮的异型性增生、乳头状瘤癌变为原位癌与浸润癌,以及腺瘤性息肉恶变为腺癌等移行现象。 本文重点描述检出的各种增生性病变与癌前病变的形态学特征,并对某些病变向癌转变的移行现象进行了分析讨论。  相似文献   

16.
Feline viral plaques (FVP) induced by papillomavirus (PV) are often hyperpigmented and flat warts. The fact that up to 47% of bowenoid in situ carcinomas (BISC), which also usually occur in the form of hyperpigmented plaques, are positive for PV antigen in immunochemistry suggests that BISC could evolve from FVP. The relationship between the presence of PV antigens and the clinical and histological features of 26 cases of feline dermatoses (clinically described as pigmented plaques and with histological diagnosis of FVP and/or BISC) was therefore determined. The cases were classified into one of the three following groups: FVP, FVP + BISC or BISC. Immunohistological detection of papillomavirus group-specific antigen was performed using a polyclonal rabbit antibovine papillomavirus antiserum. Of the seven cases in the FVP group, six were deemed positive by immunohistology as were all 10 cats in the FVP + BISC group. On the other hand, only one of the nine BISC cats was positive. The presence of both FVP and BISC lesions in some cats and the high detection rate of PV antigens in the FVP and FVP + BISC groups suggest that both conditions might have the same viral cause and that some BISC may evolve from FVP. The low rate of viral antigen detection in the BISC group indicates another cause or a loss of viral replication during the cancerogenesis.  相似文献   

17.
Inverted papillomas are uncommon papillomavirus (PV)‐induced canine skin lesions. They consist of cup‐ to dome‐shaped dermal nodules with a central pore filled with keratin. Histologically they are characterized by endophytic projections of the epidermis extending into dermis. Cytopathic effects of PVs infection include the presence of clumped keratohyalin granules, koilocytes and intranuclear inclusion bodies. Different DNA hybridization studies carried out with a canine oral papillomavirus (COPV) probe suggested that a different PV than COPV might cause these lesions. Canine papillomavirus 2 (CPV2) was discovered a few years ago in inverted papillomas of immunosuppressed beagles. Two other cases, presenting with distinct clinical and histological features have also been described. This study was carried out on four dogs with clinical and histological signs of inverted papillomas. Molecular biological analyses confirmed that PV DNA was present in all four lesions but demonstrated that the sequences in each case were different. One corresponded to COPV, the second to CPV2, and the third and fourth to unknown PVs. These findings suggest that inverted papillomas are not caused by one single PV type. Similar observations have also been made in human medicine.  相似文献   

18.
Immunohistochemical (IHC) testing and electron microscopy have implicated Papillomavirus (PV) as the etiologic agent for equine papillomas and aural plaques, but Equine papillomavirus (EPV) DNA has yet to be demonstrated in these lesions by polymerase chain reaction (PCR). The purpose of this study was to evaluate formalin-fixed, paraffin-embedded tissues from naturally occurring cases of equine papillomas, aural plaques, and sarcoids for the presence of EPV DNA by means of PCR and for the presence of PV antigen by means of IHC testing. We used EPV-specific primers that amplified a region of 384 base pairs (bp) spanning the E4 and L2 genes of the EPV genome and consensus PV primers that amplified a 102-bp region of the L1 gene. Group-specific PV structural antigens were detected with the use of a streptavidin-biotin-alkaline phosphatase IHC stain. With IHC testing, 23 of 38 papillomas, 4 of 9 aural plaques, and 0 of 10 sarcoids were positive for PV antigen; EPV DNA was found in 20 of the 38 papillomas and 1 of the 10 sarcoids but 0 of the 9 aural plaques. The consensus primers did not amplify novel PV DNA in any of the tissues. Nucleotide sequencing of viral DNA from 7 papillomas amplified with EPV-specific primers revealed DNA fragments that were 96% to 99% identical to known EPV sequences. Some samples had nucleotide substitutions in common, which suggests infection with related strains. Together, EPV DNA or PV antigen (or both) was demonstrated in 26 (68%) of the 38 equine papillomas. Although aural plaques contained PV antigen, they were negative for EPV DNA; therefore, we hypothesize that aural plaques contain a PV distinct from EPV.  相似文献   

19.
Ten types of bovine papillomavirus (BPV) have been described and there are reports of viral transmission via blood. The presence of viral DNA in lymphocytes was described to be associated with chromosome instability in these cells. This study presents an evaluation of chromosome instability in short-term peripheral lymphocyte cultures from cows presenting skin papillomatosis, compared with asymptomatic infected animals and non-infected healthy bovines. In a total of 2203 cells, 918 (42%) showed at least one chromosome aberration: 42.7 (± 7.8) in animals with papillomatosis (BPV + W), 40.2 (± 11) in asymptomatic animals (BPV-W) and 4 (± 2) in control animals. Significant differences were found between the infected group (with or without symptoms) and the control group (P < 0.0001). The increased frequencies of chromosome aberrations suggest an interaction between the virus and host cell chromatin.  相似文献   

20.
A 3‐year‐old cat from New Zealand developed three small raised non‐ulcerated plaques on the face. Serology detected antibodies against feline immunodeficiency virus (FIV). Histology of the plaque revealed epidermal hyperplasia with keratinocytes either distended with large blue‐grey cytoplasmic bodies or with shrunken nuclei surrounded by a clear halo. Papillomavirus (PV) antigen was detected immunohistochemically and feline viral plaque was diagnosed. Swabs were taken of both lesional and non‐lesional skin, and polymerase chain reactions were used to detect PV DNA. Three different PV DNA sequences were amplified, one from a Felis domesticus PV type 1 (FdPV‐1) previously amplified from a feline viral plaque, a second (FdPV‐JM) previously amplified from feline cutaneous squamous cell carcinomas, and a third FdPV‐MY that was not reported previously. All three sequences were amplified from swabs of both lesional and non‐lesional skin. These results extend the geographical range of FdPV‐1 outside North America and also demonstrate the ability of FdPV‐1 to asymptomatically infect feline skin. However, the detection of multiple PV sequences within both lesional and non‐lesional samples makes it difficult to determine whether or not any of the PVs caused feline viral plaque development in this cat. This is the first time PV DNA has been detected in a feline skin swab sample. Additionally, it is the first report of multiple PVs being detected in a single sample from a cat. This may suggest that FIV infection predisposes cats to cutaneous PV infection.  相似文献   

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