Infection by Epstein-Barr virus in Hodgkin's disease is not restricted to the Reed-Sternberg cells.

The presence of Epstein-Barr virus (EBV) DNA was analysed by a non-radioisotopic in situ hybridization procedure within eight Hodgkin's disease tissues. Seven specimens contained EBV DNA, that was found not only within the Reed-Sternberg tumour cells, but also, to a varying degree, within the surrounding lymphocytes. The staining was more diffuse in the nodular sclerosis and interfollicular types, whereas it involved only a minority of lymphocytes in cases with mixed cellularity. Appropriate controls established the specificity of these findings. The widespread expression of EBV DNA within Hodgkin's disease tissue heavily underscores the involvement of EBV in the pathogenesis of this illness.