Fig. 1

PSCs appear postnatally and increase in abundance and distance from meninges between P0 and adulthood. A, B Sagittal sections of P7 and P21 brain depicting Collagen-1a1 (Col1a1, green) PSCs (arrows) in the midbrain and in the meninges (carets). A′, B′ Higher magnification insets of large diameter, IB4+ vessels (caret indicates DAPI+ nuclei in the inner endothelium of the vessel) with Col1a1+ PSCs surrounding them (arrows). Open-arrow in B′ indicates small diameter IB4+ vessel, likely a capillary. C Graph depicting analysis of density of blood vessels with Col1a1+ PSCs for each brain area (cortex, hippocampus, striatum, hypothalamus, thalamus, midbrain and hindbrain/cerebellum) in P0, P7, P14, P21 and adult brain. Asterisks (*) mark significant differences between P0 and adult and # symbols mark significant differences between P7 and adult. D Graph depicting scoring for the average distance from the pial surface of Col1a1+ PSC associated vessels per brain region (cortex, hippocampus, striatum, hypothalamus, thalamus, midbrain and hindbrain/cerebellum). Significant differences between P0 and adult are marked (*). E Table of significant Pearson Correlation Coefficients (r) and associated p values (p) for PSC cell count and distance measurements shown in C and D. In C and D, 3 animals were scored at each time point with standard error bars. Scale bars 2 mm (A, B) and 50 µm (A′, B′)