Transcriptomic analysis of monocyte to macrophage differentiation in the colon

Intestinal macrophages rely on the constant replenishment by bone marrow derived Ly6Chigh monocytes in the adult organism. The developmental path from monocytes towards intestinal macrophages locally in the tissue is defined by the loss of Ly6C and acquisition of MHCII and CX3CR1 expression. We used microarray analysis to further characterise this local differentiation process. We FACS purified the distinct stages defining monocyte to macrophage differentiation (P1-P4), identified by their differential expression of Ly6C, MHCII and CX3CR1, from colonic cell isolates from CX3CR1GFP/+ mice. The analysis was done using GeneChip® Mouse Gene 1.0 ST arrays from Affymetrix. Each population was analysed in triplicates. CX3CR1GFP/+ mice were used between 6-12 weeks of age.