To compare up-regulation of genes following CpG activation, we performed microarray analysis of activated macrophages from B6 and F1(B6xMOLF) mouse strains. Cells were activated for 0, 2 and 4 hrs with 200nM of type B CpG. Levels of mRNA for many genes differened dramatically between the strains Overall design: Peritoneal macrophages were elicited from pertoneal cavity of mice 3 days after thioglycollate injection. The cells were plated overnight at a density of 5 million cells per 100 mm dish and activated the next day with 200 nM CpG. Total RNA was isolated with TRIZOL followed by reverse transcrition, fragmentation and labeling accroding the manufacture's (Affymetrix) recommendations