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Figure 6
The expression of cxcl11aa is upregulated in macrophages upon infection and requires an active Myd88-immune signaling. (A) Expression of cxcl11aa in FACS-sorted macrophages (MΦ, mpeg1:mCherrypositive) and its infection-dependent induction (relative to negative/Mock fraction). (B) Mm- (or Mock-) injected larvae (>100 per replicate per condition) were dissociated at 5 dpi. Induction of cxcl11aa does not require the RD1 pathogenicity locus and mutants of the cognate receptor of cxcl11aa (cxcr3.2−/−) are still able to upregulate cxcl11aa at comparable levels to wt. (C–E) RNA was isolated from pools of >10 whole larvae collected at 4 dpi. Eight hundred CFU of RD1 mutant bacteria vs. 100 CFU of wildtype Mm were injected to reach a comparable infection level at 4 dpi. Dependency of cxcl11aa induction from myd88. Expression levels (C), representative burden analysis (D) and representative burden pictures (E) derive from larvae collected at 4 dpi. RNA was isolated from pools of >10 whole larvae. Each point in (D) represents 1 infected larva from a representative pool. Two hundred CFU of wildtype Mm were injected in myd88+/+ larvae vs. 100 and 200 CFU injected in myd88−/− larvae to reach a comparable infection level at 4 dpi. Quantification of total bacterial pixels was obtained using dedicated bacterial pixel count program (64). Scale bar in (E) 200 μm. Statistical significance was analyzed by one-way ANOVA with Sidak post-hoccorrection on ln(n)-transformed relative induction folds (real time PCRs) or untransformed data (infection burden). Significance (P-value) is indicated with: ns, non-significant; *P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001. Error bars: mean ± s.e.m.