Etsuko Kumagai

Chromosomal abnormalities in a patient with smoldering adult T-cell leukemia: evidence for a multistep pathogenesis

A cytogenetic study was performed on peripheral blood cells from a patient with smoldering adult T-cell leukemia (ATL). Four types of primary abnormal clones were found upon examination of a large number of karyotypically analysed cells cultured with and without phytohemagglutinin (PHA). However, human T-cell leukemia virus (HTLV) proviral DNA was confirmed to be monoclonal. This discrepancy can be explained by the hypothesis that these four primary abnormal clones were all derived from a leukemic clone with a normal karyotype and the same integration site of HTLV proviral DNA.

Clinical study on the serum levels of immunosuppressive acidic protein in patients with adult T-cell leukemia.

Serum levels of immunosuppressive acidic protein (IAP) were measured in patients with adult T-cell leukemia (ATL) in order to clarify its significance in this disease. The mean levels in patients with both acute (854 +/- 404 micrograms/ml) and chronic ATL (439 +/- 103 micrograms/ml) were significantly higher than in sera of healthy controls (367 +/- 104 micrograms/ml). However, mean levels in patients with smoldering ATL, healthy T-cell lymphotropic virus type 1 (HTLV-1) carriers and healthy controls showed no differences. Levels in crisis in chronic and smoldering ATL were similar to those in patients with acute ATL. Serial measurements of serum IAP in a number of patients revealed that the levels reflected each patients clinical course, suggesting a potential for use in evaluating the effects of chemotherapy.

Sensitivity to electrical stimulation of human immunodeficiency virus type 1 and MAGIC-5 cells

To determine the sensitivities to low electrical potential of human immunodeficiency virus type 1 (HIV-1) and its target cells, HIV-1 and MAGIC-5 cells were directly stimulated with a constant direct current potential of 1.0 V (vs. Ag/AgCl). HIV-1 was incubated for 3 h at 37°C on a poly-L-lysine-coated indium-tin oxide electrode, and then stimulated by an electrical potential. MAGIC-5 cells were seeded onto the electrically stimulated HIV-1 and cultured for 3 days at 37°C. HIV-1-infected cells were measured by multinuclear activation via a galactosidase indicator assay. MAGIC-5 cells were also stimulated by an electrical potential of 1.0 V; cell damage, proliferation and apoptosis were evaluated by trypan blue staining, cell counting and in situ apoptosis detection, respectively. HIV-1 was found to be damaged to a greater extent by electrical stimulation than the cells. In particular, after application of a 1.0-V potential for 3 min, HIV-1LAI and HIV-1KMT infection were inhibited by about 90%, but changes in cell damage, proliferation and apoptosis were virtually undetectable. These results suggested that HIV-1 is significantly more susceptible to low electrical potential than cells. This finding could form the basis of a novel therapeutic strategy against HIV-1 infection.