Identification of a New Transcriptional Signature of Pre‐Adipocytes in Human Subcutaneous White Adipose Tissue

OBJECTIVE: White adipose tissue (WAT) expansion occurs through generation of new adipocytes from adipose progenitor cells (APC). The objective of this study was to characterize and validate a new transcriptional profile of APC. METHODS: Single-cell (sc)/nuclei (sn) RNA-Seq was performed on nuclei from whole WAT (n = 20), cells from WAT stromal vascular fraction (n = 5), and cultured APC in vitro (n = 8) using ICELL8 smart-Seq technology. Additional snRNA-Seq was performed on WAT using 10x genomic platform. Pseudotime analyses and differentiation of hiPSCs was used to track the temporal patterns of novel gene signatures. Immunohistochemistry was performed to validate a new marker. RESULTS: A pre-adipocyte population was found across the four independent datasets that expressed known pre-adipocyte markers (ZNF423 and DLK1) in addition to genes typically associated with neurogenes (DPP10, PTRPT, CTNNA2, NRXN3, CTNNA2, PTPRD, CNTNAP2 and RBFOX1). The expression of these genes were temporally regulated with adipocyte differentiation. Immunohistochemistry analyses confirmed these pre-adipocytes are located in the neurovascular niche of WAT but are not neurons or endothelial cells. CONCLUSIONS: This work has defined a new transcriptional signature of pre-adipocytes in human subcutaneuous WAT that are distinct from mesencyhmal stem cell populations and represent novel targets for WAT expansion.