Lsm700 inverted laser confocal microscope

HRP cells and vascular organoids (VO) were cultured as described above. At the experiments’ endpoints, the cells and VO samples were cryo-sectioned or flat-mounted, fixed in 4% paraformaldehyde (VVR Life Science), permeabilized by incubation in 0.05% Triton X-100, and blocked with 10% normal goat serum (NGS). The fixed samples were then incubated with the primary antibodies (Table 1). After washing with PBST buffer, the staining signals were visualized by goat anti-rabbit IgG (H + L) Cyanine5, goat anti-mouse IgG (H+L) Alexa Fluor 488, and goat anti-rat IgG (H+L) pacific blue. The non-specific staining and background tissue autofluorescence were established by incubating the sections of vascular organoids with secondary antibodies alone (Fig. S1). The cell nuclei were stained with DAPI (1:5,000). The slides were mounted with a ProLong Diamond antifade reagent (Thermo-Fisher) and imaged with an LSM 700 inverted laser confocal microscope (Carl Zeiss, Oberkochen, Germany).