Establishment of a Three-Dimensional In Vitro Model of Equine Papillomavirus Type 2 Infection

Area of Science:

• Veterinary Oncology
• Equine Virology
• Carcinogenesis Research

Background:

• Equine papillomavirus type 2 (EcPV2) is linked to equine genital squamous cell carcinoma (SCC).
• Mechanisms of EcPV2-driven neoplastic progression are not fully understood.
• A research model is needed to study EcPV2 carcinogenesis.

Purpose of the Study:

• To establish a primary equine cell culture model for EcPV2 infection.
• To investigate EcPV2-induced neoplastic progression in vitro.
• To provide a tool for studying equine genital SCC.

Main Methods:

• Generated 3D raft cultures from equine penile tissues (skin, plaques, SCCs).
• Utilized histological, molecular, and immunohistochemical analyses.
• Compared raft cultures with natural tissue sections for morphology and marker expression.

Main Results:

• Raft cultures recapitulated normal skin differentiation, hyperplasia, and dysplasia mirroring natural tissues.
• EcPV2 oncogene (E6/E7) transcription correlated with neoplastic progression.
• Tumor/proliferation markers (p53, Ki67, MCM7) expression increased with disease severity in rafts.

Conclusions:

• 3D equine raft cultures accurately reflect ex vivo EcPV2-associated lesions.
• This model is valuable for studying EcPV2-induced carcinogenesis in equids.
• The model aids research into the mechanisms of equine genital SCC development.