From the Institute of Biophysics and Biochemistry, University of Tehran
Abstract: (3619 Views)
Treatment of human promonocytic leukemic cell line U937 with mild
hyperthermia in the temperature range of 40-43°C resulted in differentiation of
these cells into monocyte/macrophage-like cells in a heat dose and time dependent
manner. This process was accompanied by marked morphological, functional and
proliferational changes. U937 cells which normally grow in supension in the
logarithmic phase of growth showed marked inhibition in proliferation after
treatment with heat in comparison with controls, without significant decrease in
cell viability. The clonogenicity of these cells in semisolid agar cultures was also
reduced upon heat treatment. Heat treatment increased the fraction of cells which
could reduce nitro blue tetrazolium (NBT) and phagocytize latex particles. These
data demonstrate that heat treatment can induce differentiation ofU937 cells into
monocytes/macrophages and thus have possible applications in treatment of
leukemia. Temperatures higher than 43°C or exposures of longer than 30 minutes
at such high temperatures resulted in cytotoxic effects.