Identification of inflammatory genes suppressed by heat shock. Mus musculus

To clarify inflammatory genes whose expression is suppressed at high temperatures, we performed comprehensive analysis of gene expression by using a DNA microarray. Two independent primary cultures of mouse embryo fibroblasts (MEF1 and MEF2) were treated with LPS for 4 hours, or treated with LPS for 4 hours after the pretreatment with heat shock at 42˚C for 1 hour, and we identified 100 genes that undergo more than a 3-fold increase with LPS treatment. Remarkably, 86 genes (86%) underwent less than a 2-fold increase after combined treatments with heat shock and LPS in MEF1 and MEF2 cells. Overall design: Total RNAs were prepared from two primary cultures of mouse embryo fibroblasts (MEF) derived from two independent embryos at embryonic day 15.5 (ICR mice). Cells were maintained at 37˚C (Control), treated with lipopolysaccharide (LPS, E. coli 0127:B8, Sigma, 1 μg/ml) for 4 hours, or treated with LPS for 4 hours after the pretreatment of heat shock at 42˚C for 1 hour. Gene expression was analyzed by using GeneChip Mouse Genome 430 2.0 Array (Affymetrix, Santa Clara, CA).