Single cell transcriptomics suggest that human adipocyte progenitor cells constitute a homogeneous cell population

Area of Science:

• Cell Biology
• Stem Cell Biology
• Metabolic Research

Background:

• Adipose stem cells (ASCs) regulate adipogenesis and are implicated in metabolic complications.
• Distinct ASC subtypes have been suggested in animal models, but human ASCs require further characterization for therapeutic applications.
• Understanding ASC heterogeneity is crucial for their use in regenerative medicine.

Purpose of the Study:

• To characterize adipose stem cell (ASC) populations in human subcutaneous white adipose tissue (scWAT) using unbiased single-cell transcriptomics.
• To investigate potential distinct subtypes of ASCs within human scWAT.
• To provide a deeper characterization of ASCs for their increasing use in cell-based therapies.

Main Methods:

• Single-cell RNA sequencing (transcriptomics) was performed on 574 cells from the stroma vascular fraction (SVF) of human scWAT from four healthy women.
• Clustering and t-distributed stochastic neighbor embedding (t-SNE) were used to analyze transcriptomic data.
• Identified cell populations were mapped to known WAT cell types using gene expression data from flow cytometry-sorted SVF.

Main Results:

• Four distinct cell populations were identified: three subtypes of adipose tissue-resident macrophages and one large, homogeneous population of ASCs.
• Pseudotemporal ordering suggested minor differences in ASC differentiation stages, but gene expression variations were too small to define distinct subtypes.
• Single-cell transcriptomics did not reveal evidence for distinct ASC subtypes in healthy human scWAT.

Conclusions:

• In healthy individuals, adipose stem cells (ASCs) in subcutaneous white adipose tissue (scWAT) appear to constitute a single, homogeneous population.
• Current single-cell transcriptomic analysis cannot subdivide human ASCs into distinct subtypes.
• These findings suggest a common origin for human adipocytes derived from ASCs in scWAT, with implications for understanding fat tissue development and therapeutic applications.