Figure 5: Expression of CCL8 mRNA by CD169⁺ macrophages under inflammatory condition.

(a) CD169⁺ and CD169⁻ myeloid cells were purified from the LP of WT naive and DSS-induced colitis mice (top) by a cell sorter. Total RNA extracted from fractionated myeloid cells was hybridized to the Affimetrix Mouse Genome 430 2.0 Array chip. Heat map of mRNA upregulated (bottom left) or downregulated (bottom right) in CD169⁺ macrophages (R1) of colitis mice relative to their expression in CD169⁺ macrophages of naive mice. Expression levels are displayed as fold induction over naive controls (log₂). (b) Upregulated expression of CCL8 mRNA in CD169⁺ macrophages (R1) 5 days after DSS administration was validated by qRT–PCR. (c) CCL8 mRNA expression 5 days after DSS administration was selectively upregulated in CD169⁺ cells. Values are presented as fold induction compared with the expression levels in naive CD169⁺ macrophages (b) or cells in R4 (c). Average values and s.d. of triplicate experiment are shown. *P<0.05, Student’s t-test, **P<0.01, one-way analysis of variance (ANOVA). (d) CCL8 mRNA expression is upregulated in response to DSS administration in LP CD11b⁺ cells. LP CD11b⁺ cells in the colon were enriched by magnetic sorting from mice administered with DSS. CCL8 mRNA expression at the indicated time point was quantified by qRT–PCR and expressed as fold induction compared with naive CD11b⁺ cells. Data are representative of two independent experiments. *P<0.05, one-way ANOVA.