Fig 2: Quantification of Dpp4+ lineage traced mature adipocytes in the omental and retroperitoneal depots. GFP+/PLIN1+ mature adipocytes were quantified and normalized the total number of PLIN1+ adipocytes per section. Gonadal WAT quantification was included for reference. Open shapes = female mice, solid shapes = male mice.

Fig 3: The Dpp4CreERmouse enables robust and specific labeling of DPP4+ cells in the intestine and liver. (A) Histological examination of the intestine and liver were conducted as a positive control for Dpp4CreER; mGFP labeling of cells known to express high levels of Dpp4. The pulse timepoint is depicted in the left panels and a 3-week chow diet chase timepoint on the right panels. DPP4+ intestinal epithelial cells are sloughed off and replaced by unlabeled cells at the chase timepoint. [mGFP: lineage traced cells (green), DPP4: cells currently expressing DPP4 (magenta), DAPI: nuclei (blue); scale bar = 380 μM]. Individual antibody staining is represented in grayscale on the right-side inset panels (inset scale bar = 100 μm). (B) Quantification of DPP4 enzymatic activity from serum (left panel) or dissected RI tissue (right panel) of wild type (WT) and Dpp4CreER mice.

Fig 4: Dpp4+ progenitor cells contribute to basal adipogenesis in subcutaneous depots. (A) Flow cytometric analysis of SVF cells (CD45(−)/DAPI(−)) from subcutaneous WAT of Dpp4CreER; mGFP mice at the pulse timepoint. mGFP+ lineage traced cells are shown as a green overlay on top of mGFP(−) cells, which are depicted in gray. (B) IHC staining of subcutaneous inguinal WAT (iWAT) at the pulse timepoint. [mGFP: lineage traced cells (green), cells currently expressing DPP4 (magenta), PLIN1: mature adipocytes (red), DAPI: nuclei (blue); scale bar = 380 μM]. Individual antibody staining is represented in grayscale on the right-side inset panels (inset scale bar = 100 μM). (C) IHC staining of Dpp4CreER iWAT (top panels) and axillary WAT (axWAT, bottom panels) following 18 weeks of feeding chow (left) or HFD.

Fig 5: Dpp4+ progenitors contribute extensively to adipogenesis in the murine omentum. (A) Gross histology showing the anatomic location of the mouse omentum. The murine greater omentum is a translucent sheet of collagen-filled connective tissue (reticular interstitium) that extends from the greater curve of the stomach and is draped over the pancreas and intestine. The inferior edge of the omentum is filled with adipose tissue (omental adipose). (B) IHC staining of omental adipose tissue from Dpp4CreER; mGFP mice at the pulse timepoint [mGFP: lineage-traced cells (green), DPP4: cells currently expressing DPP4 (magenta), PLIN1: mature adipocytes (red), DAPI: nuclei (blue); scale bar = 380 μM]. Individual antibody staining is represented in grayscale on the right-side inset panels (inset scale bar = 100 μM). (C) H&E and IHC staining of omental WAT from Dpp4CreER; mGFP mice under chow (left panels) or HFD (right panels) feeding conditions.