HUMAN ACUTE MYELOID LEUKEMIAS MAY BE ETIOLOGICALLY ASSOCIATED WITH NEW HUMAN RETROVIRAL INFECTION

The etiology of human acute myeloid leukemias (AML) remains uncertain. In order to examine the possibility of retroviral etiology in AML, we determined retroviral antigens related to HTLV-I in leukemic cell sam ples from 32 AML cases and peripheral blood mononuclear cells (PBMNCs) from 20 healthy donors by D-IGSS with high sensitivity and specificit y, reverse transcriptase (RT) activity by a simple and sensitive non-r adioisotopic RT assay, and retroviral particles by electron microscopy . The HTLV-I-related antigens were detected in 50.0% (16/32) of fresh leukemic cell samples and 87.5% (28/32) of cultured leukemic cell samp les. The HTLV-I-related antigen-positive cells in fresh and cultured l eukemic samples were 10.2% and 52.8%, respectively. Both frequency and level of HTLV-I-related antigens in cultured samples were much higher than in fresh samples. In contrast, no HTLV-I-related antigens were f ound in normal hematopoietic cells from 20 healthy donors. Further stu dy results show that RT activity was detected not only in HTLV-I-relat ed antigen-positive samples, but was also well correlated with the lev el of HTLV-I-related antigens in these samples, and preferred Mn++ to Mg++ as a cation. Moreover, typical retroviral particles were localize d in most cultured HTLV-I-related antigen-positive samples by immunoel ectron microscope, These data suggest that hu man acute myeloid leukem ias may be etiologically associated with new hu man retroviral infecti on. Copyright (C) 1996 Elsevier Science Ltd.