Chemical inhibition of both Cxcr3 receptors affects only macrophages expressing Cxcr3.2 and renders a similar bacterial burden and macrophage recruitment efficiency as cxcr3.2 mutants. After bath exposure of 3‐day‐old larvae to either the CXCR3‐specific inhibitor NBI 74330 (50 µM) or vehicle (DMSO 0.01%), before and after tail‐amputation showed that cell recruitment to the site of injury was reduced in macrophages expressing Cxcr3.2, namely, WT and cxcr3.3–/– (A and C), whereas no further decline in cell recruitment was observed in cxcr3.2 mutants (B and D). Chemical inhibition of both Cxcr3 receptors with NBI 74330 (25 µM) before and after systemic infection with Mm resulted in a lower bacterial burden at 4 dpi than in the vehicle‐treated control and resembles the cxcr3.2 mutant phenotype (E and F). The data of 3 independent replicates were pooled and are presented as mean ± sem. A Kruskal‐Wallis test was conducted to assess significance (ns P > 0.05, ****P ≤ 0.0001) in the macrophage recruitment assay. Only the P‐values among each condition (vehicle/NBI 74330) within each group are shown (D). Bacterial burden data were analyzed using a two‐tailed t‐test and data are shown as mean ± sem (****P ≤ 0.0001)
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