Use of polymerase chain reaction in detection of Marek's disease and reticuloendotheliosis viruses in formalin-fixed, paraffin-embedded tumorous tissues.

A simple PCR method was developed for the detection of Marek's disease (MD) and reticuloendotheliosis (RE) in formalin-fixed paraffin-embedded (FFPE) tissues, and for the detection of MD in tissues only preserved in 10% neutral buffered formalin. MD virus (MDV) and RE virus proviral DNA were detected in FFPE tissues stored for over 20 yr. MDV was also detected in tissues only preserved in formalin for up to 6 mo. The data indicate that PCR of formalin-fixed and FFPE tissues is a simple and valuable tool that can be used to identify MD and RE infection. The method described in this paper is a good alternative to any biologic or immunohistochemical assay to confirm the detection of MD and RE, as it does not require shipping frozen tissues to the diagnostic laboratory.