Heat Shock Proteins in Normal and Leukemic Blood Cells

Abstract

Heat shock proteins (HSPs) are though to represent a ubiquitous cellular response to heat or stress. We tested whether HSPs can be induced in hairy cells, other human leukemic cells, and normal lymphocytes, and whether there are additive or synergistic effects between heat shock and interferon-α_2b (IFN-α_2b) on these cells. We analyzed lysates of cells from 22 patients (6 with hairy cell leukemia, 12 with other acute and chronic leukemias and lymphocytes of 4 normals) after exposure to a heat shock and/or IFN-α_2b by one-dimensional polyacrylamide gel electrophoresis. In all cells a pattern of HSPs was readily induced with prominent bands identified at approximately 115, 90, and 65 kD. None of these major proteins appeared to represent the previously described IFN-α_2b induced band at 80 kD. IFN-α_2b by itself was not found to induce HSPs. We conclude that a pattern of HSPs can readily be induced in a variety of normal and leukemic human blood cells. IFN-α_2b is not a HSP inducer in these cells. The previously described IFN-induced p80 is apparently not a HSP.