Downregulation of major histocompatibility complex class I in bovine papillomas

Araibi, E.H., Marchetti, B., Ashrafi, G.H. and Campo, M.S. (2004) Downregulation of major histocompatibility complex class I in bovine papillomas. Journal of General Virology, 85(10), pp. 2809-2814. (doi: 10.1099/vir.0.80128-0)

Abstract

Bovine papillomavirus (BPV) induces papillomas in cattle; in the great majority of cases, these regress due to the host immune response, but they can persist and progress to malignancy. Even in the absence of malignant transformation, BPV infection persists for a significant period of time before activation of the host immune system, suggesting that the host immune system is unaware of, or disabled by, BPV. E5 is the major oncoprotein of BPV, which, in addition to its transforming properties, downregulates the expression and transport to the cell surface of major histocompatibility complex class I (MHC I). Here, it is shown that co-expression of MHC I and E5 in papillomas caused by BPV-4 infection is mutually exclusive, in agreement with the inhibition of surface MHC I expression by E5 that is observed in vitro. The inhibition of MHC expression in E5-expressing papilloma cells could explain the long period that is required for activation of the immune response and has implications for the progression of papillomas to the malignant stage; absence of peptide presentation by MHC I to cytotoxic T lymphocytes would allow the infected cells to evade the host cellular immune response and allow the lesions to persist.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Ashrafi, Dr Gholam Hossein and Campo, Professor Saveria and Marchetti, Dr Barbara
• Authors: Araibi, E.H., Marchetti, B., Ashrafi, G.H., and Campo, M.S.
• Subjects: S Agriculture > SF Animal culture > SF600 Veterinary Medicine; Q Science > QR Microbiology > QR355 Virology
• College/School: College of Medical Veterinary and Life Sciences
• Journal Name: Journal of General Virology
• Publisher: Society for General Microbiology
• ISSN: 0022-1317
• ISSN (Online): 1465-2099
• Copyright Holders: Copyright © 2004 Society for General Microbiology
• First Published: First published in Journal of General Virology 85(10):2809-2814
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher