Macrophage Responses to SEA and S. mansoni Eggs
(A) Zebrafish larvae at 30 h post fertilization (hpf) with hindbrain ventricle (HBV) outlined. Scale bar, 300 μm.
(B) Mean macrophage recruitment to HBV 3 h post-injection with phosphate-buffered saline (PBS), SEA, or Mycobacterium marinum (Mm); ANOVA with Dunnett’s post-test.
(C) S. mansoni egg in HBV immediately after implantation. Scale bar, 75 μm.
(D) Representative images of macrophage responses to S. mansoni eggs observed 5 dpi; minimal recruitment, few if any macrophages recruited with ≤6 in contact with the egg (arrowheads); macrophages recruited, several macrophages recruited with >6 in contact with the egg (arrowheads) but without aggregation; granuloma; macrophage aggregation in which individual macrophages cannot be distinguished as separate, either partially (arrowhead) or completely encasing the egg. Scale bar, 75 μm.
(E) Prevalence of macrophage responses to implanted eggs as defined in (D), representing 8 experiments, each constituting a separate batch of eggs and a separate clutch of zebrafish larvae, as detailed in Table S1. Dotted line divides the proportion of partial (23%) and complete (5%) granulomas. Also see Figure S1; Table S1; Video S1.