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Biology subjects

Barry, F.

Publications and source records attributed to Barry, F..

3 recordsLinked to original sources

Spatial transcriptomics defines the mechanisms of hiPSC derived stem cell mediated repair in human articular cartilage

We here determined therapeutic efficacy and mode-of-action of human induced pluripotent-derived therapeutic stem cells (hiMSCs) across in vivo mouse and ex vivo human osteoarthritis models. hiMSC treatment in DMM-mice significantly reduced OARSI damage scores, which was affirmed by a decrease in the catabolic marker Mmp13 and an increase in the anabolic marker Col2. These treatment effects appeared, irrespective of modifying factors such as xeno-free media or thermosensitive hydrogel carrier. Subsequently treatment of hiMSC+gel in human osteoarthritic cartilage explants showed a transcriptome-wide significant activation of the cholesterol and sterol synthesis pathways marked by genes such as MVD, DHCR7, MSMO1, FABP3. Additionally, we showed that these changes alleviated OA-associated imbalances of the cellular Zinc-ion homeostasis pathways, represented by genes such as MT1F, MT1G, MT1H and SLC30A1. Spatial transcriptomics then sensitively captured that hiMSC+gel treatment evoked, specifically at the superficial cartilage layer, a consistent upregulation of healthy chondrocyte markers such as CHAD, ACAN, FRZB, and SOX9, alongside a suppression of catabolic and inflammatory mediators such as SERPINE1, SPP1, MMP13, ADAMTS5. Our findings link therapeutic outcomes of hiMSC treatment to precise spatially resolved molecular changes in human tissue, that would otherwise be obscured by heterogeneous cell populations. Collectively our study highlighted that hiPSC-derived stem cell therapy (hiMSCs) could provide a scalable off-the-shelf solution to treat osteoarthritis, with strong prospects for clinical applications in the near future.

developmental biology↗

Abnormal pro-inflammatory immune cell responses precede clinical onset of hypertensive disorders of pregnancy

BackgroundHypertensive disorders of pregnancy (HDP) are significant contributors to maternal morbidity and mortality as well as to long-term cardiovascular health, with an inequitable burden among Black individuals. While there is growing interest in the possibility that inflammatory responses are involved with HDP, work to date has primarily been cross-sectional, and immune cell profiling has focused on cell phenotyping that may not capture relevant functional properties of the immune cells. ObjectiveTo examine whether an inflammatory cellular response is found in the blood of pregnant women preceding the clinical onset of HDP. Study designThis nested case-control study included 27 pregnant women who later developed HDP and 73 who had a healthy pregnancy delivered at term, all of whom provided blood samples during the second trimester. ResultsWe observed a greater abundance of peripheral blood T cells in individuals later diagnosed with HDP. Among these were CD161+ CD4 T cells that showed increased expression of pro-inflammatory cytokines, including GM-CSF and TNF. Similarly, monocytes from these individuals exhibited increased expression of pro-inflammatory cytokines. Anti-inflammatory T cells and monocytes were not altered in those with versus without a future diagnosis of HDP. ConclusionWe identify a pro-inflammatory cellular immune signature in pregnant individuals destined to have HDP. Immune signatures may serve as a new biomarker to identify subsets of individuals at particular risk for HDP and/or point to new therapeutic targets to prevent HDP.

immunology↗

Transcriptional profiling of early differentiation of primary human mesenchymal stem cells into chondrocytes

Articular cartilage has only very limited regenerative capacities in humans. Tissue engineering techniques for cartilage damage repair are limited in the production of hyaline cartilage. Mesenchymal stem/stromal cells (MSCs) are multipotent stem cells and can be differentiated into mature cartilage cells, chondrocytes, which could be used for repairing damaged cartilage. Chondrogenesis is a highly complex, relatively inefficient process lasting over 3 weeks in vitro. In order to better understand chondrogenic differentiation, especially the commitment phase, we have performed transcriptional profiling of MSC differentiation into chondrocytes from early timepoints starting 15 minutes after induction to 16 hours and fully differentiated chondrocytes at 21 days. Transcriptional gene regulatory networks (GRN) were identified using time-course clustering and upstream-regulator predictions which revealed that cells start epigenetic reprogramming as early as 2 hours after induction and commit to differentiation within 4-6 hours. After that they adapt their gene expression to cater for differentiation specific protein production. These results suggest that interventions to improve the frequency and efficiency of differentiation should target early processes.

molecular biology↗