LATENT MEMBRANE-PROTEIN ANTIBODY REACTS WITH NORMAL HEMATOPOIETIC PRECURSOR CELLS AND LEUKEMIC BLASTS IN TISSUES LACKING EPSTEIN-BARR-VIRUSGENOME BY POLYMERASE CHAIN-REACTION

Epstein-Barr virus (EBV)-encoded latent membrane protein (LMP) has bee n detected in various reactive and neoplastic lymphoproliferations and in some epithelial malignancies. However, data are lacking on LIMP im munoreactivity in normal and neoplastic hematopoietic cells. Therefore , the authors studied LMP staining in 29 paraffin-embedded tissues con taining these cells and correlated the findings with polymerase chain reaction (PCR) analysis for a EBV-BAM HI W genome sequence in 15 of th ese cases. Latent membrane protein immunostains showed strong uniform marking of normal early myeloid and erythroid precursors, whereas neut rophils, bands and late normoblasts were negative. Leukemic myeloblast s and lymphoblasts were also strongly positive for LMP. Polymerase cha in reaction analysis show ed no evidence of EBV-BAM HI W genome in 13 cases with amplifiable DNA. This study indicates normal hematopoietic precursor cells and leukemic blasts mark strongly with monoclonal LMP antibody. Furthermore, the absence of EBV genome in these tissues sugg ests a lack of specificity of monoclonal LMP for EBV-infected cells in the marrow.