Epstein-Barr virus and Hodgkin's disease: a comparative immunological, in situ hybridization, and polymerase chain...

During recent years numerous studies have demonstrated the presence of Epstein-Barr virus (EBV) in tissues affected by Hodgkin's disease (HD). The percentage of cases with evidence of EBV infection has varied among the different studies, a positive result being highly dependent on the sensitivity of the method employed. In this study three different methods of detecting EBV in 48 cases of 'classical' HD (33 cases of nodular sclerosis and 15 cases of mixed cellularity) were compared: Immunohistochemistry (IH) for detection of latent membrane protein-1 (LMP-1), in situ hybridization (ISH) for detection of Epstein-Barr virus early RNAs (EBER 1 and 2), and polymerase chain reaction (PCR) for detection of a reiterated 110 base-pair EBV genomic sequence of the BamHI region. In 14 cases (29%) Hodgkin's (H) and Reed-Sternberg (RS) cells were positive for LMP-1 using IH, and in 21 cases (44%) positive signals were seen in H-RS cells with EBER 1 and 2 probes using ISH. A few EBER-positive non-malignant lymphocytes were seen in 17 cases. Thirty-two cases (71%) were EBV-positive by PCR. It is concluded that the PCR technique is the most sensitive method for detecting EBV in HD. However, this method cannot provide information about the cellular localization of EBV. ISH with EBER 1 and 2 probes is superior to immunohistochemical detection of LMP-1 with regard to sensitivity. The advantage that the latter two methods have over the PCR techniques is that it is possible to analyse whether the EBV infection occurs in the H-RS cells or in the admixed non-malignant cell population. Furthermore, this study supports the observation that EBV is associated with a considerable number of HD cases.