Figure 3. Blockade of fluid absorption alters HEV structure in PPs.
(a) Representative images taken by confocal microscopy of an HEV from the PP of an untreated control mouse or a mouse treated for 3 days with PEG in drinking water. left and middle panels: HEV ECs and FRCs were marked by staining with anti-MAdCAM1 and anti-PDPN respectively. right panel: Contact points between HEV perimeter and surrounding perivascular FRCs. Scale bars = 20um. Bar graph: Total quantification of FRC:HEV contact points from confocal imaging. Data represented as mean ± SEM of three independent experiments (n=10 mice per treatment). Unpaired two tailed Student’s t test was used to compare groups (** P ≤ 0.01). (b) Transmission electron micrograph of PP HEVs. top panel: control. bottom panel: treated for 3 days with PEG in drinking water. ECs false colored in red. Separations between endothelial cell and basement membrane marked by yellow arrows. Lymphocytes marked by “L”. Scale bar = 2um. Representative of two independent experiments. (c) Schematic representation of HEV structure in PPs from untreated (upper) and PEG-treated (lower) mice.