Detection of Antibodies against Epidermodysplasia Verruciformis-Associated Canine Papillomavirus 3 in Sera of Dogs from Europe and Africa by Enzyme-Linked Immunosorbent Assay

Abstract

The role of papillomaviruses (PVs) in the development of canine cancers is controversial. However, recently a novel canine PV (CPV3) was detected in a dog affected with a condition reminiscent of epidermodysplasia verruciformis (EV). The aim of the present study was to investigate the seroprevalence of CPV3 by using generic enzyme-linked immunosorbent assays (ELISAs) for the detection of antibodies against either canine oral PV (COPV) or CPV3. Therefore, the capsid proteins of both PV types were expressed as glutathione S-transferase fusion protein antigens and adsorbed to glutathione-casein-coated ELISA plates. After showing that PV type-specific antibodies could be detected in the sera from dogs with confirmed COPV or CPV3 infection, CPV3-and COPV-seropositive samples were detected in two sets of canine sera collected in Switzerland and South Africa, respectively. We found specific antibodies against COPV and CPV3 among the tested sera and also a large number that were positive for both antigens. The seroprevalences of PV antibodies of 21.9% (COPV) and 26.9% (CPV3) among the tested dogs from South Africa were higher than those among the dogs from Switzerland at 10.5% (COPV) and 1.3% (CPV3). Our data suggest a need for further CPV-related seroepidemiological surveys in different countries, especially in the context of clinical manifestations and possible breed predispositions. For this purpose, the newly developed ELISAs can be a useful tool.Papillomaviruses (PVs) are small, icosahedral, nonenveloped DNA viruses with mucosal and skin tropism which are associated with various hyperplastic, dysplastic, and neoplastic conditions in humans and animals (21). More than 100 types of human PVs (HPVs) have been described, and more are continuously being discovered (8). The role of HPVs in the development of human diseases, i.e., cervical carcinomas or epidermodysplasia verruciformis (EV)-associated skin carcinomas, is well established, and pathomechanisms have been the focus of many studies (14,23,30,35,48). Indeed, both PCR-and enzyme-linked immunosorbent assay (ELISA)-based techniques are commonly used to carry out HPV-related epidemiologic studies (2, 25).In contrast, the role of PVs in the development of canine cancers remains uncertain, although a clinical counterpart to human EV has been described in dogs with PV infections (28). Until now, only four canine PVs (CPVs) have been unambiguously identified and sequenced (7,42,43,46). The first and best-known CPV, canine oral PV (COPV), affects mostly juvenile dogs and causes warts with a typical cauliflower-like appearance located in the oral cavity and other mucous membranes (32). Since COPV-affected dogs recover spontaneously and specific antibodies protect them from reinfection, COPV infection is not considered a life-threatening condition (32). Although COPV infection is endemic in most dog populations, there never was a great demand for serological surveys, and systematic serological data concerning the prevalence of COPV infection are thus far unavailable. A dis...

Serum antibodies and DNA indicate a high prevalence of equine papillomavirus 2 (EcPV2) among horses in Switzerland

“…The primers EcPV2_L1 ELISA forward (5′‐GGA ATT CCT GTA CCT ACC CCC CAA‐3′) and EcPV2_L1 ELISA reverse (5′‐GGA ATT CTT ATG CCT TCC TTT TCT TGG TG‐3′) were designed to introduce an Eco RI restriction site at both ends of the PCR product. The amplified L1 open reading frame was then cloned into the Eco RI site of pGEX‐6P‐1 (Pharmacia, Uppsala, Sweden), expressed in Escherichia coli strain BL21 and prepared as described before …”

“…The optical density was measured with a sunrise ® ELISA‐reader (Tecan, Männedorf, Switzerland) after 45 min at 405 nm wavelength. All sera were tested in parallel against CPV1 (canine papillomavirus 1)_L1 antigen, which served as a control for unspecific or cross‐reactive antibody binding . The amount of antigen was equalized based on serial dilutions tested with anti‐glutathione S ‐transferase antibody (GE Healthcare, Piscataway, NJ, USA).…”

Antibody titres against canine papillomavirus 1 peak around clinical regression in naturally occurring oral papillomatosis

“…To screen for serum antibodies, the L1 protein of CPV1 was expressed in Escherichia coli and coated onto ELISA plates as described previously . All dog sera were tested in triplicate diluted 1:500, avoiding more than one peripheral well per triplicate.…”

“…All dog sera were tested in triplicate diluted 1:500, avoiding more than one peripheral well per triplicate. Sera previously tested positive or negative served as controls . For the analysis, the mean of the two optical densities (ODs) closest to each other was taken, while the third OD of the triplicate was disregarded.…”

“…Serum antibody titres can also help detect past infections using specific enzyme‐linked immunosorbant assays (ELISAs). Prevalence rates of 10.5 and 21.9% have been reported for CPV1 antibodies in asymptomatic dogs . Despite data showing antibody induction in controlled laboratory conditions, antibody responses to natural CPV infections, induced by supposedly lower viral loads, have not been studied in dogs .…”