Biomedical subjects

Davina M Anderson

Publications and source records attributed to Davina M Anderson.

3 recordsLinked to original sources

PubMed2003

Therapeutic immunisation with COPV early genes by epithelial DNA delivery.

Following challenge with COPV (canine oral papillomavirus), DNA plasmids encoding COPV L1, E1 or E2 protein were delivered into oral mucosal and cutaneous sites in beagles using particle-mediated immunotherapeutic delivery (PMID). Two weeks post-challenge, a priming dose of 8 microg DNA was delivered followed by a booster dose after a further two weeks. A group of control dogs were vaccinated using plasmid DNA encoding Hepatitis B virus surface (HBVs) gene. All of the control animals developed warts at the vast majority of sites (94%). All of the animals given wild type L1, E1, or E2 developed warts at most sites (88%, 75%, and 88%, respectively). The animals given codon optimised E2 however, were protected from wart growth with only one tiny lesion seen on a single animal that persisted for only a few days. The E1 codon optimised group was also significantly protected with a far lower number of smaller warts (48%) that persisted for a shorter duration. These data suggest that therapeutic immunisation by PMID with papillomavirus early genes is effective and emphasizes the importance of antigen load in the generation of protective responses to papillomavirus proteins.

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PubMed2002

Intraepithelial DNA immunisation with a plasmid encoding a codon optimised COPV E1 gene sequence, but not the wild-type gene sequence completely protects against mucosal challenge with infectious COPV in beagles.

DNA plasmids encoding the open reading frames of canine oral papillomavirus (COPV) nonstructural early genes E1, E2, or E7 protein were delivered into both oral mucosal and cutaneous epithelial sites in beagle dogs using particle-mediated immunotherapeutic delivery (PMID) technology. Control dogs were vaccinated with plasmid encoding either hepatitis B virus surface antigen (HBVs) or COPV L1. Using a prophylactic immunisation protocol, a priming dose of plasmid DNA was followed by a booster dose 6 weeks later. Four weeks after boost, all dogs were challenged with infectious COPV particles. Following viral challenge, as shown previously (M. A. Stanley et al., 2001, Vaccine 19, 2783-2792), mucosal papillomas developed in the negative-control HBVs vaccinated dogs, but all animals in the COPV L1 group were fully protected from disease development. In the early gene-vaccinated groups five of six in the E1-vaccinated dogs, two of six in E2-vaccinated dogs, and three of six in the E7-vaccinated beagles developed oral papillomas. Compared to the HBVs negative-control group the oral papillomas that did develop in the early-gene vaccinated beagles were significantly smaller, shorter in duration, and fewer in number. Taken together the disease burden was markedly reduced and this was statistically significant. In a second experiment one group of animals was vaccinated with plasmid encoding the wild-type COPV E1 gene, and a separate group was vaccinated with plasmid encoding a synthetic codon-optimised COPV E1 gene sequence. None of the codon-optimised E1-vaccinated animals developed papillomas at any challenge site. However, all animals vaccinated with wild-type E1 had papillomas. These data suggest that immunisation by PMID with papillomavirus early genes can significantly impact upon subsequent disease development and that full protection can be achieved using improved vectors encoding codon-optimised gene sequences perhaps emphasizing the importance of antigen load in the generation of protective responses to papillomavirus proteins.

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PubMedDate not supplied

Nasal dermoid sinus cysts in the dog.

OBJECTIVE: To describe the clinical and morphologic characteristics of nasal dermoid sinus cysts in the dog. STUDY DESIGN: Retrospective clinical study. ANIMALS: Six client-owned dogs. METHODS: Medical records (1995 to 1999) of 6 dogs that had a discharging sinus in the midline of the nose removed surgically were reviewed for signalment, physical examination, surgical and histopathologic findings, and outcome. RESULTS: Three golden retrievers, 1 springer spaniel, 1 cocker spaniel, and 1 Brittany spaniel with a history of intermittent discharge from a small opening in the midline on the bridge of the nose at the junction between the nasal planum and the skin were identified. The condition was unresponsive to antibiotic therapy, and previous surgical excision had been unsuccessful in 3 dogs. None of the dogs had any other congenital defects, and all dogs responded to complete surgical excision of the tract and cyst. On histopathologic examination of excised tissue, there were adnexal structures along a tract lined with stratified squamous epithelium, consistent with a developmental abnormality of ectodermal tissue. CONCLUSIONS: The lesions were diagnosed as nasal dermoid sinus cysts, similar to the congenital condition described in humans. Nasal dermoid sinus cysts are rare developmental defects related to abnormal development of the pre-nasal space and may extend into the cranial vault causing cerebral abscesses or recurrent meningitis. Complete surgical excision has a good prognosis. CLINICAL RELEVANCE: This is a new condition that should be added to the surgical differential diagnosis for a discharging sinus over the external nares in dogs.

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