Fig 2: CD74+ ASC-enrichment improves fat graft quality. A, Average volume retention, expressed as a percentage with respect to baseline volume, measured over 8 weeks. B, Representative reconstructed microcomputed tomography images of enriched fat and fat only at 8-weeks postgrafting. There was a trend toward greater fat retention in mice receiving grafts of fat enriched with CD74+ ASCs, compared to fat grafts enriched with CD74- or US ASCs and fat alone. C, Representative H&E-staining of explanted fat grafts 8 weeks after implantation at ×10 magnification. D, Scoring of graft architectural characteristics based on H&E-stained sections. Explanted fat grafts enriched with CD74+ ASCs had greater integrity (****P < .001), less inflammation (****P < .0001), and were less fibrotic (****P < .001) compared to the fat grafts enriched with CD74- or US ASCs and fat alone. Scale bar = 100 µm. *P < .05; **P < .01; ****P < .0001. ASC, adipose-derived stromal cell; US, unsorted

Fig 3: Dermal fibroblast subpopulation composition in irradiated skin overlying fat grafts. There were significantly fewer papillary (top left) (****P < .0001) and reticular (top right) (****P < .0001) fibroblasts, and significantly greater lipofibroblasts (bottom left) (**P < .01) and zigzag (bottom right) (****P < .0001) fibroblasts in skin overlying CD74+ ASC-enriched fat compared to skin overlying fat enriched with CD74- and US ASCs or fat alone. ASC, adipose-derived stromal cell; US, unsorted

Fig 4: Distribution of CD74+ ID3+ ILCFR in human tonsillar B cell follicles.a Histocytometry analysis showing the frequency of CD19− CD8− CD4− CD74+ ID3+ ILCFR in a tonsillar tissue section (tonsil #1) and b Overlay showing the distribution of CD74+ ID3+ ILCFR (red dots) with respect to CD19+ B cells (dark blue dots) and CD4+ T cells (yellow dots) in the same tonsil. c Bar graph summarizing the frequencies of intra- and extra- follicular ILCFR (CD19− CD8− CD4−CD74+ ID3+) as a frequency of total ILCFR in five tonsils. d Confocal images showing the tonsil area imaged, distribution of B cell follicles as denoted by CD19 (dark blue) and Ki67 (cyan) as well as ID3 positive cells (red). e Close up of a B cell follicle. Dotted lines demarcate the area of the follicle (LZ) as well as the dark zone (DZ) as defined by the density of Ki67 staining (cyan). B cells are shown in blue (CD19+), proliferating cells in cyan (Ki67+), ID3 in red, CD4 in yellow and CD8 in magenta. f Zoomed in details of the red rectangular enclosures shown in (e). The location of a CD74+ (green) ID3+ (red) cell is shown with respect to the positioning of CD19+ (blue) Ki67 (cyan) cells or CD8+ (magenta) and CD4+ (yellow) lymphoid cells. g Zoomed in close-ups confirming the positioning and phenotype of ILCFR (CD19-CD4− CD8− CD74+ ID3+). Images were acquired at ×40 (NA 1.3) with no zoom. Images shown are sequential digital magnifications of 150 um (d), 30 um (e), 10 um (f), and 2 um (g). A total of five biologically independent human tonsils were imaged.

Fig 5: ILCFR are expanded in chronic HIV viral infection in human lymph nodes.In a plots shows frequency of ILCFR in human HIV− or chronic infection HIV+ lymph nodes. Gated on live cells, CD45+lin−CD3−CD19−CD161−CD127lo/−. In b the graph shows frequency of ILCFR among CD45+ lymph node cells in both HIV− and HIV+ individuals (unpaired, two-tailed nonparametric t-test; ***p = 0.0008; df = 5, 95% CI: (−0.02406 to −0.01140), t = 7.198; Mean ± SD). c shows frequency of total live CD45+ cells in both groups from b. In d the plots show Bcl6 expression in ILCFR in human HIV− or HIV+ lymph nodes, gated on CD45+lin−CD3−CD19−CD161−CD127lo/−CXCR5+CD74+ from the gates in a, and e shows the graph of frequency of Bcl6+ among CD45+ lymph node cells in HIV− and HIV+ individuals (unpaired, two-tailed nonparametric t-test; **p = 0.0061; df = 5, 95% CI: (−0.01809 to −0.00504), t = 4.559; Mean ± SD) (2 independent experiments) (n = 3 or 4 biologically independent tonsils per group).