Fig. 5

Nanoparticle-mediated SEC deletion. (a) Whole-embryo and tissue level views at 48 hpi of the blood vasculature in kdrl:GFP transgenic control embryos, embryos injected with 1 mg/mL clodronic acid, or embryos injected with liposomes containing 1 mg/mL clodronic acid (DSPC or DOPC liposomes). Complete deletion of the caudal vein is observed in embryos injected with DSPC liposomes containing clodronic acid (brackets and asterisks). (b) Schematic representation of blood flow in control embryos or embryos injected with DSPC liposomes containing 1 mg/mL clodronic acid. Blue indicates venous or capillary blood vessels, and red indicates arterial blood vessels. Arrowheads indicate direction of blood flow (based on observations from Movie S1). The removal of the CV (dashed lines) leads to a rerouting of blood flow through the DLAV. (c) Quantification of PCV length in injected embryos. Bar height represents median values, dots represent individual data points, and brackets indicate significant values (**: p < 0.01, ***: p < 0.001) based on Kruskal–Wallis and Dunn’s tests with Bonferroni correction for multiple testing. n = 6 individually injected embryos per group (in two experiments). (d) Progression of SEC deletion. Individual frames from Movie S2 at indicated time points after injection of DSPC liposomes containing 1 mg/mL clodronic acid, injected into kdrl:GFP transgenic embryos. SEC fragmentation in this case is observed mostly between 12 hpi and 16 hpi, followed by a gradual loss of fluorescence or removal of cellular debris. (e) Tissue level view of distribution of DSPC liposomes containing 1 mg/mL clodronic acid at 1 hpi in stab2^ibl2 and sibling control embryos. (f) Whole-embryo and tissue level views at 48 hpi of the blood vasculature in kdrl:GFP transgenic stab2^ibl2 and sibling embryos. Embryos were injected with DSPC liposomes containing 1 mg/mL clodronic acid. Complete deletion of the caudal vein is observed in sibling control (brackets and asterisks), but not stab2^ibl2 mutant embryos. (g) Schematic representation of blood flow in sibling control embryos or stab2^ibl2 homozygous mutants, both injected with DSPC liposomes containing approximately 1 mg/mL clodronic acid. Blue indicates venous or capillary blood vessels, and red indicates arterial blood vessels. Arrowheads indicate direction of blood flow (based on observations from Movie S3). The removal of the CV (dashed lines) leads to a rerouting of blood flow through the DLAV in control embryos but not in stab2^ibl2 homozygous mutants. (h) Quantification of PCV length in injected embryos. Bar height represents median values, dots represent individual data points, and brackets indicate significant values (***: p < 0.001) based on Mann–Whitney test.