Fig. 2

Fig. 2

Mycobacteria Mediate CCR2-Dependent Monocyte Recruitment by Actively Inducing CCL2 in Resident Macrophages

(A) ccl2 messenger RNA levels (mean ± SEM of three biological replicates) induced at 3 hr after caudal vein infection of 2 dpf wild-type or myeloid cell-deficient fish with 250–300 wild-type Mm.

(B–D) In situ hybridizations against zebrafish ccl2 mRNA following hindbrain ventricle infections with vehicle (bacterial media) (B), 80 wild-type Mm (C), 80 Mm - PGL− (D). Black arrows, ccl2 mRNA-positive phagocytes; white arrows ccl2 mRNA-negative phagocytes. Scale bar, 50μm. Results representative of three independent experiments.

(E) Mean brain resident macrophage numbers of csfr1^+/− and csfr1^−/− zebrafish at 2dpf. Results representative of two independent experiments.

(F) Mean resident macrophage and monocyte recruitment from 5 to 150 mpi in the HBV of csfr1^+/− or csfr1^−/− fish after infection with 80 wild-type Mm.

(G) ccl2 messenger RNA levels (mean ± SEM of three biological replicates) induced at 3 hr after caudal vein infection of 2 dpf wild-type fish with 250–300 live or heat-killed wild-type Mm.

(H) Mean resident macrophage and monocyte recruitment from 5 to 120 mpi in the HBV of wild-type fish after infection with 80 live or heat-killed (HK) wild-type Mm.

(I) Mean resident macrophage and monocyte recruitment from 5 to 150 mpi in the HBV of csfr1^+/− or csfr1^−/− fish after infection with 80 Mm - PDIM⁻.

(J) Mean resident macrophage and monocyte recruitment from 5 to 150 mpi in the HBV of wild-type fish after infection with 80 live or heat-killed (HK) Mm - PDIM⁻.

(K) Mean resident macrophage and monocyte recruitment from 5 to 120 mpi in the HBV of wild-type fish after infection with 80 wild-type or PDIM⁻ Mm.

Results in (F) and (H) through (K) representative of at least three independent experiments.