Viral Factors Involved in Marek’s Disease Virus (MDV) Pathogenesis

Purpose of Review: Marek’s disease virus (MDV) is a highly oncogenic alphaherpesvirus that causes various clinical symptoms including fatal lymphomas in chickens. The virus encodes several MDV-specific genes that play a major role in viral pathogenesis. This review will focus on the recent advances in our understanding of how these viral factors contribute to pathogenesis and tumor formation. Recent Findings: Several viral factors involved in MDV pathogenesis have been identified including the major oncoprotein Meq, the viral chemokine vIL-8, MDV-encoded microRNAs, RLORF4, RLORF5a, pp14, pp38, a virus-encoded telomerase RNA (vTR), and viral telomeric repeats (TMRs). Our current knowledge of the role of these viral factors in MDV pathogenesis has immensely increased over the last few years; however, more work needs to be done to completely understand the mechanisms for most of them. Summary: MDV pathogenesis and tumor formation is a complex process. Deciphering the mechanisms of viral factors involved in MDV pathogenesis and lymphomagenesis will not only improve our understanding of this neoplastic disease but will also provide new strategies for vaccine development against this deadly pathogen. © 2018, Springer Nature Switzerland AG.