Immunotherapy of Equine Sarcoids-From Early Approaches to Innovative Vaccines.

Horses and other equid species are frequently affected by bovine papillomavirus type 1 and/or 2 (BPV1, BPV2)-induced skin tumors termed sarcoids. Although sarcoids do not metastasize, they constitute a serious health problem due to their BPV1/2-mediated resistance to treatment and propensity to recrudesce in a more severe, multiple form following accidental or iatrogenic trauma. This review provides an overview on BPV1/2 infection and associated immune escape in the equid host and presents early and recent immunotherapeutic approaches in sarcoid management.

Papillomavirus-like Particles in Equine Medicine.

Papillomaviruses (PVs) are a family of small DNA tumor viruses that can induce benign lesions or cancer in vertebrates. The observation that animal PV capsid-proteins spontaneously self-assemble to empty, highly immunogenic virus-like particles (VLPs) has led to the establishment of vaccines that efficiently protect humans from specific PV infections and associated diseases. We provide an overview of PV-induced tumors in horses and other equids, discuss possible routes of PV transmission in equid species, and present recent developments aiming at introducing the PV VLP-based vaccine technology into equine medicine.

Bovine Papillomavirus Type 1 or 2 Virion-Infected Primary Fibroblasts Constitute a Near-Natural Equine Sarcoid Model.

Equine sarcoids are common, locally aggressive skin tumors induced by bovine papillomavirus types 1, 2, and possibly 13 (BPV1, BPV2, BPV13). Current in vitro models do not mimic de novo infection. We established primary fibroblasts from horse skin and succeeded in infecting these cells with native BPV1 and BPV2 virions.

Influenza virus vector iNS1 expressing bovine papillomavirus 1 (BPV1) antigens efficiently induces tumour regression in equine sarcoid patients.

Bovine papillomaviruses types 1 and 2 (BPV1, BPV2) commonly induce skin tumours termed sarcoids in horses and other equids. Sarcoids seriously compromise the health and welfare of affected individuals due to their propensity to resist treatment and reoccur in a more severe form. We have developed influenza (Flu) A and B virus vectors that harbour a truncated NS1 gene (iNS) assuring interferon induction and co-express shuffled BPV1 E6 and E7 antigens for sarcoid immunotherapy.

Type-specific L1 virus-like particle-mediated protection of horses from experimental bovine papillomavirus 1-induced pseudo-sarcoid formation is long-lasting.

Equine sarcoids are common therapy-resistant skin tumours induced by bovine papillomavirus type 1 or 2 (BPV1, BPV2) infection. We have previously shown that prophylactic vaccination with BPV1 L1 virus-like particles (VLPs) efficiently protects horses from experimental BPV1-induced pseudo-sarcoid development. Here, we assessed BPV1 L1 VLP vaccine-mediated long-term protection from experimental tumour formation in seven horses 5 years after immunization with three different doses of BPV1 L1 VLPs, and three unvaccinated control animals.

Potential of a BPV1 L1 VLP vaccine to prevent BPV1- or BPV2-induced pseudo-sarcoid formation and safety and immunogenicity of EcPV2 L1 VLPs in horse.

We have previously shown that immunization of horses with bovine papillomavirus type 1 (BPV1) L1 virus-like particles (VLPs) is safe and highly immunogenic and that BPV1 and bovine papillomavirus type 2 (BPV2) are closely related serotypes. Here we evaluated the protective potential of a BPV1 L1 VLP vaccine against experimental BPV1 and BPV2 challenge and studied the safety and immunogenicity of a bivalent equine papillomavirus type 2 (EcPV2)/BPV1 L1 VLP vaccine. Fourteen healthy horses were immunized with BPV1 L1 VLPs (100 µg per injection) plus adjuvant on days 0 and 28, while seven remained unvaccinated.

Epidemiologic analysis of a sarcoid outbreak involving 12 of 111 donkeys in Northern Italy.

Equine sarcoids develop upon bovine papillomavirus type 1 or 2 (BPV1, BPV2) infection in conjunction with trauma and represent the most common tumour disease in horses and other equids, including donkeys. In face of a sarcoid outbreak involving 12 of 111 donkeys and mules at the 'Rifugio degli Asinelli', a subsidiary charity organization of The Donkey Sanctuary, non-invasively collected sample material including crusts, dandruff, swabs and hair roots was collected from sarcoid-affected and 26 healthy donkeys, as well as dandruff from a grooming kit and tabanids caught from or in the vicinity of sarcoid patients. In addition five previously collected sarcoids stored in formalin were provided.

Bacterial meningitis after sinus surgery in five adult horses.

Objective: To report meningoencephalitis as a complication after paranasal sinus surgery in 5 horses.

Study Design: Case series.

Animals: Adult horses (n = 5).

Inoculation of young horses with bovine papillomavirus type 1 virions leads to early infection of PBMCs prior to pseudo-sarcoid formation.

Bovine papillomavirus types 1 and 2 (BPV-1 and BPV-2) are known to induce common equine skin tumours, termed sarcoids. Recently, it was demonstrated that vaccination with BPV-1 virus-like particles (VLPs) is safe and highly immunogenic in horses. To establish a BPV-1 challenge model for evaluation of the protective potential of BPV-1 VLPs, four foals were injected intradermally with infectious BPV-1 virions and with viral genome-based and control inocula, and monitored daily for tumour development.

Radiation therapy communication: equine hemangioma.

A 13-month-old Standardbred Colt had a recurrent hemangioma at the level of the coronary band. Multiple excisions had led to a nonhealing skin and hoof defect. Using 14 MV electrons, a total dose of 36 Gy was administered, given as six fractions of 6 Gy twice a week.

Evaluation of a canine cranial cruciate ligament repair system for use in equine laryngoplasty.

Objective: To report the use of a nylon suture system (Canine Cranial Cruciate Ligament Repair System; Securos Inc Veterinary Orthopedics) as a prosthesis for equine laryngoplasty.

Study Design: Experimental and prospective clinical study.

Animals: Cadaver specimens (n = 5) and 7 horses with left laryngeal hemiplegia.