The cellular composition and functionality of adipose tissue are key determinants of metabolic diseases associated with adipose tissue dysregulation, such as obesity. We hypothesized that distinct subpopulations with unique gene expression profiles and functional characteristics exist within human adipocytes.
Dedifferentiated adipocytes (DFAT), obtained by ceiling culture of human adipocytes, were analyzed using single-cell RNA sequencing (10x Genomics). Clustering analysis identified one subpopulation with a particular gene signature containing muscle cell genes which was further characterized by bulk-sequencing and analyzed alongside different cohorts of human adipose tissue.
This subpopulation, named cluster 7 (C7), was isolated by FACS using two specific surface markers: cluster of differentiation 36 (CD36) and melanoma cell adhesion molecule (MCAM/CD146). Upon differentiation into adipocytes, the FACS-isolated CD36+/CD146+ cells (C7∗) showed an increased oxygen consumption rate compared to CD36-/CD146-cells (control cells) and non-sorted cells. Bulk RNA-sequencing revealed important pathways regulated in the differentiated C7∗ subpopulation that may contribute to its increased metabolic activity. Furthermore, the relative abundance of this specific cluster varied across eleven different human donors, demonstrating an inverse correlation between the proportion of C7∗ cells and the body mass index (BMI) of the respective donor. Importantly, a subset of genes regulated within this subpopulation also correlates with clinically relevant metabolic parameters, including weight, BMI, glycated hemoglobin, and plasma insulin, when analyzed alongside the gene expression of a large cohort of human subcutaneous adipose tissue (1759 donors).
Our results not only characterize DFAT cells derived from human adipose tissue, but also identify a specific subpopulation with increased energy expenditure that may play a role in body weight control. Future efforts to identify possible therapeutic targets or to promote the enrichment or activation of these energy-burning cells in adipose tissue might be useful in the field of cardiometabolic diseases.
Copyright © 2025 The Authors. Published by Elsevier GmbH.. All rights reserved.

In systemic lupus erythematosus (SLE), neutrophil dysregulation and neutrophil extracellular traps (NETs) formation contribute to disease pathogenesis, potentially worsening the autoimmune response. Although research indicates NETs' involvement in various autoimmune conditions, their relationship with regulatory T cells (Tregs) in SLE remains elusive. In this study, in vivo experiments were involved in administering NET injections to C57BL/6 and MRL/Ipr mice. In vitro, a co-culture system facilitated interaction between Tregs and NETs. Proteomic analysis elucidated NET composition, while RNA sequencing delineated their impact on Treg differentiation. We demonstrated that increased NET levels correlate inversely with Treg abundance in SLE patients, influencing both their proportion and functionality. NET administration reduced Treg levels and induced lupus-like symptoms in C57BL/6 mice, exacerbating symptoms in MRL/Ipr mice. DNase I treatment mitigated NET effects, restoring Treg levels and alleviating symptoms. RNA sequencing revealed altered gene expression in naïve CD4+ T cells exposed to NETs. Additionally, proteomic analysis showed S100A10 protein changes between SLE patients and healthy controls, hindering Treg differentiation. NETs influence TLR-4 of naïve CD4+ T cells via S100A10, thereby modulating Treg proportion and functionality. These findings highlight the critical role of NETs in Treg differentiation in SLE, suggesting that targeting NETs may provide a novel therapeutic approach.
© 2024 Wiley‐VCH GmbH.

Variant histone H3.3 is thought to be critical for survival of many cells, since it is deposited in expressed genes, a feature different from core histones. For example, H3.3 deletion leads to embryonic lethality in mice. However, requirement of H3.3 in later stage of development has remained unclear. The aim of this work was to elucidate the role of H3.3 for development of myeloid lineage, important for innate immunity. We conditionally knocked out (cKO) the H3.3 genes in myeloid progenitor cells differentiating into bone marrow derived macrophages (BMDMs). Progenitor cells lacking H3.3 were defective in replication, suffered from extensive DNA damage, and underwent apoptosis. Surviving H3.3 cKO cells expressed many interferon stimulated genes (ISGs) throughout differentiation. Further, H3.3 cKO BMDMs possessed chromatin accessible sites, and histone posttranslational modifications consistent with the gene expression profiles, Accordingly, H3.3 cKO BMDMs retained general nucleosomal structure genome wide. In summary, H3.3 is required for proliferation of myeloid progenitor cells, but is in large part dispensable for differentiation of BMDMs.

High levels of the polyunsaturated fatty acid arachidonic acid (AA) within the ovarian carcinoma (OC) microenvironment correlate with reduced relapse-free survival. Furthermore, OC progression is tied to compromised immunosurveillance, partially attributed to the impairment of natural killer (NK) cells. However, potential connections between AA and NK cell dysfunction in OC have not been studied.
We employed a combination of phosphoproteomics, transcriptional profiling and biological assays to investigate AA's impact on NK cell functions.
AA (i) disrupts interleukin-2/15-mediated expression of pro-inflammatory genes by inhibiting STAT1-dependent signaling, (ii) hampers signaling by cytotoxicity receptors through disruption of their surface expression, (iii) diminishes phosphorylation of NKG2D-induced protein kinases, including ERK1/2, LYN, MSK1/2 and STAT1, and (iv) alters reactive oxygen species production by transcriptionally upregulating detoxification. These modifications lead to a cessation of NK cell proliferation and a reduction in cytotoxicity.
Our findings highlight significant AA-induced alterations in the signaling network that regulates NK cell activity. As low expression of several NK cell receptors correlates with shorter OC patient survival, these findings suggest a functional linkage between AA, NK cell dysfunction and OC progression.
© 2024. The Author(s).

Human pluripotent stem cells (hPSCs) represent a powerful model system to study early developmental processes. However, lineage specification into trophectoderm (TE) and trophoblast (TB) differentiation remains poorly understood, and access to well-characterized placental cells for biomedical research is limited, largely depending on fetal tissues or cancer cell lines. Here, we developed novel strategies enabling highly efficient TE specification that generates cytotrophoblast (CTB) and multinucleated syncytiotrophoblast (STB), followed by the establishment of trophoblast stem cells (TSCs) capable of differentiating into extravillous trophoblast (EVT) and STB after long-term expansion. We confirmed stepwise and controlled induction of lineage- and cell-type-specific genes consistent with developmental biology principles and benchmarked typical features of placental cells using morphological, biochemical, genomics, epigenomics, and single-cell analyses. Charting a well-defined roadmap from hPSCs to distinct placental phenotypes provides invaluable opportunities for studying early human development, infertility, and pregnancy-associated diseases.
© 2024 The Author(s).