Gene expression profiles of mouse monocytes deficient in the CCL2/CCR2 chemokine signaling

Gene-level transcriptome analysis of monocyte mRNA derived from mice that are genetically deficient of the Ccl2 gene or Ccr2 gene The CCL2/CCR2 chemokine axis is critical in monocytes mobilization and innate immunity. Although mice deficient in either gene manifest similar phenotype, such as reduced atherosclerosis, some biologic processes are disrupted in starkly different ways in these mice. We found in a Her2/neu driven mammary carcinoma model, the absence of Ccl2 inhibits tumor growth and prolongs survival, while genetic deletion of Ccr2 has the opposite effect. One of the postulated mechanisms is that Ccl2 and Ccr2 affect monocyte development in different manners. This experiment was designed to compare the whole transcriptome of monocytes that are deficient in either Ccl2 or Ccr2, with the hypothesis that differential development of these monocytes will manifest as differential gene expression profiles. We purified monocytes from peripheral blood of mice by MACS (magnetic activated cell sorting) technique. Given the relative scarcity of mouse monocytes in the peripheral blood, we pooled the white blood cells from 5 mice in each sample, and compared 3 replicate samples from wild type Balb/cJ mice, and Ccl2-/- and Ccr2-/- mice on the same genetic background. We analyze each sample using the Affymetrix GeneChip Mouse Gene 1.0 ST Array. Array data was processed using the dChip software.