Fig. 1: Maternal–fetal activation of ChP 5-HT2C evokes apocrine secretion of proteins into the CSF.
From: Choroid plexus apocrine secretion shapes CSF proteome during mouse brain development
a, Placenta-attached ex vivo imaging setup. b, Overview image of exposed E16.5 4V ChP and time points showing tissue Ca2+ response to WAY-161503. c, Heat map of E16.5 ChP cellular Ca2+ responses to direct WAY-161503 (WAY) exposure. d, Timeline of readouts of apocrine secretion. e, Representative confocal images of E12.5 mouse brain 30 min after maternal saline (control) or WAY-161503 delivery; scale bars 100 µm. f, RT–qPCR analysis of ChP Fos expression at E14.5 (left; N = 11 embryos, three litters) and E16.5 (right; N = 10 embryos, three litters). F, fluorescence. g, Quantification of the data in h; N = 20 embryos, four litters per condition. h, SEM of E14.5 (top) and E16.5 (bottom) LV ChP; scale bars, 20 µm. i, Representative confocal images of E16.5 LV ChP 30 min after maternal WAY-161503 delivery; scale bars, 20 µm; Ac-Tubulin, acetylated tubulin. j, Top: protein-retention expansion microscopy of E16.5 LV ChP 30 min after maternal WAY-161503 delivery. Bottom: fetal GW21 LV control ChP (left) or after a 30-min incubation with WAY-161503 (right). White arrows indicate TTR-containing aposomes. Scale bars, 10 µm. k, E12.5, E14.5 and E16.5 CSF protein concentration (conc.) 30 min after maternal saline (E12.5 N = 4, E14.5 N = 7, E16.5 N = 8) or WAY-161503 (E12.5 N = 3, E14.5 N = 6, E16.5 n = 7) delivery. Each point represents pooled CSF from one litter. l, Western blot for TTR and SOD3 in E16.5 mouse CSF. A cropped Ponceau stain of each membrane is displayed as a loading control. m, Western blot for TTR from human ChP-conditioned artificial CSF (aCSF) following exposure to WAY-161503 or vehicle control. A cropped Coomassie blue stain is displayed as a loading control. Full blots and stains are shown in Supplementary Fig. 2. All data are presented as mean ± s.e.m. P values were calculated by two-way analysis of variance (ANOVA) with a Sidak correction for f, g and k. Images in b represent experiments repeated three times with similar results, in i represent experiments repeated ten times with similar results and in l represent experiments repeated five times with similar results. The experiment in m was only performed once. Panel d created with BioRender.com.
