Date of Award
Doctor of Philosophy
To investigate the effect of heat-shock (HS) on the gene expression of mammalian blood cells, human, mouse and rabbit blood cells were cultured and incubated at elevated temperatures or in the presence of ethanol or sodium arsenite, and the patterns of polypeptides synthesized by these cells analyzed by one- and two-dimensional polyacrylamide gel electrophoresis (PAGE). The in vitro exposure of human lymphocytes or human myeloma cells to short term increases in incubation temperature (41(DEGREES) - 43(DEGREES)C) results in the enhanced synthesis of heat-shock proteins (HSPs) of 110, 100, 90, 70 and 65 kilodaltons, and the depressed synthesis of many polypeptides normally synthesized at a control (37(DEGREES)C) temperature. This response is dependent on the duration and severity of the HS. Heat-shocked mouse spleen cells, and mouse and rabbit peripheral blood lymphocytes, synthesize HSPs with molecular masses and isoelectric points similar to those synthesized by human lymphocytes. HSP synthesis by mouse spleen cells is transcription dependent, and is a transient event, since a gradual recovery of normal patterns of protein synthesis is observed following HS. Spleen cells from mice exposed to whole-body thermal stress also synthesize HSPs comparable to those synthesized by similar cells heat-shocked in vitro.;Cultured mouse spleen cells treated with arsenite or ethanol exhibit new and/or enhanced synthesis of most of the HSPs, but do not exhibit enhanced synthesis of the 100 kDa HSP. Short-term concurrent exposure of mouse lymphocytes to HS and a level of ethanol, which individually do not induce detectable HSP synthesis, results in the pronounced synthesis of HSPs similar to those seen following exposure to higher levels of either stress applied separately. Thus, hyperthermia and ethanol stress can act synergistically to dramatically change the gene expression of mouse spleen cells. Quantification of the IgG constitutively synthesized and secreted in vitro by control and heat-shocked mouse spleen cells and splenic B lymphocytes revealed no differences between control and heat-shocked cells. These results demonstrate that synthesis and secretion of IgGs is not affected by thermal stresses sufficient to induce HSP synthesis and depress the synthesis of other polypeptides normally synthesized at a control temperature.
Rodenhiser, David Ivan, "Characterization Of Heat-shock And Chemical-stress Induced Changes In The Gene Expression Of Mammalian Lymphocytes" (1986). Digitized Theses. 1558.