Extended Data Fig. 2: Gremlin1 expressing FRCs are localized outside the B-cell follicle in Peyer’s patches.
From: Gremlin 1+ fibroblastic niche maintains dendritic cell homeostasis in lymphoid tissues
a, Fraction of SLN Grem1+ cells in FRCs from Fig. 1a for each replicate separately. b, Left: Gating strategy for identification of FDC (follicular dendritic), MRC (marginal reticular) and FRC (fibroblastic reticular) cells within the CD45−Ter119−CD31−PDPN+ gate; Middle: relative proportion; Right: absolute numbers of EYFP+ (Grem1+) in FRC, MRC and FDC subsets from Grem1 Cre.YFP mice (n = 4) post-tamoxifen induction. c, Top Left: UMAP dimensionality reduction of stromal cells isolated from mouse spleen, colored by cluster membership. Right/bottom left: UMAP as on top left, colored by indicated marker gene expression. Bottom right: Fraction of Grem1+ fibroblasts shown on the top left. d, EYFP in CD45− stromal cells in bone marrow and bones of Grem1 Cre.YFP mice (n = 3) post-tamoxifen induction. e, Plots showing in-vitro EYFP expression by lymph node FRCs in control and 4-hydroxytamoxifen treated cultures (4-OHT) from Grem1 Cre.YFP mice. (f, g) Imaging of lymph node sections from Grem1 Cre.YFP mice post-tamoxifen induction. f, Anti-YFP (Grem1+ FRCs), anti-PDPN (stromal cells) staining in SLN. Scale bars, 150μm. g, Anti-YFP (Grem1+ FRCs), anti-PDPN (stromal cells), anti-PNAd (HEV), anti-LYVE-1 (lymphatic, LEC) staining in SLN. Scale bars, 150μm. h, Imaging of spleen sections from Grem1 Cre.YFP mice post-tamoxifen induction; stained for anti-B220 and anti-YFP (left). Scale bars, 150μm; (right) enlargement of sections on the left. Scale bars, 75μm. i, Imaging of Peyer’s patches from Grem1 Cre.YFP mice post-tamoxifen induction, stained for anti-YFP (Grem1+ FRCs), anti-PDPN (stromal cells), anti-B220 (B cells). Scale bars, 150μm; zoomed image on right, scale bar, 75μm. Data representative of two independent experiments (b, d); data pooled from three independent experiments (e) [control n = 3; OHT treated n = 6]; data representative of images from 13 SLN, three independent experiments (f, g); representative image from 5 spleens, two independent experiments (h); representative images from 4 Peyer’s patches, two independent experiments (i). Data shown as mean ± SEM.
