Fig. 6

Vegf Pathway Blockade Inhibits In Vivo Growth of Wild-Type but Not pcaA Mutants

(A) Bacterial burden of larvae with or without the Tg(hsp70l:dn-vegfaa) transgene at 5 dpi, infected with either wild-type or pcaA mutant M. marinum. Expression of the transgene induces a reduction in wild-type M. marinum burden compared with larvae without the transgene. Expression of the transgene had no effect on the bacterial burdens of larvae infected with the PcaA mutant strain. ^∗p < 0.05; ^∗∗p < 0.01; one-way ANOVA with Tukey's multiple comparison post-test. n = 31 and n = 55 for wild-type infections in larvae without or with the Tg(hsp70l:dn-vegfaa) transgene, respectively; n = 33 and n = 39 for pcaA mutant infections in larvae without or with the Tg(hsp70l:dn-vegfaa) transgene, respectively.

(B) Quantification of abnormal vasculature during wild-type infections for Tg(kdrl:EGFP)⁺ larvae with or without the Tg(hsp70l:dn-vegfaa) transgene. The double transgenic larvae were present as a subset of the cross between the Tg(kdrl:EGFP) and Tg(hsp70l:dn-vegfaa) transgenic lines. Induction of the Tg(hsp70l:dn-vegfaa) transgene results in a reduction in infection-induced angiogenesis. ^∗p < 0.05, Student's t test. n = 16 and n = 25 for larvae without or with the Tg(hsp70l:dn-vegfaa) transgene, respectively.

(C) Representative images of vascularization in larvae with the Tg(hsp70l:dn-vegfaa) transgene (right panels) and without (left panels). Upper panels: bright field, with the dotted line depicting regions shown in the lower panels. Scale bars, 500 μm. Middle panels: merge of vasculature and infection. Lower panels: vasculature alone. Scale bars, 100 μm. All quantitation performed blind to genotype.