The mechanisms regulating hematopoietic stem and progenitor cell (HSPC) fate choices remain ill-defined. Here, we show that a signalling network of p190-B RhoGAP-ROS-TGF-β-p38 balances HSPC self-renewal and differentiation. Upon transplantation, HSPCs express high amounts of bioactive TGF-β1 protein, which is associated with high levels of p38 activity and loss of HSC self-renewal in vivo. Elevated levels of bioactive TGF-β1 are associated with asymmetric fate choice in vitro in single HSPCs via p38MAPK activity and this is correlated with the asymmetric distribution of activated p38MAPK. In contrast, loss of p190-B, a RhoGTPase inhibitor, normalizes TGF-β levels and p38MAPK activity in HSPCs and is correlated with increased HSC self-renewal in vivo. Loss of p190-B also promotes symmetric retention of multi-lineage capacity in single HSPC myeloid cell cultures, further suggesting a link between p190-B-RhoGAP and non-canonical TGF-β signalling in HSPC differentiation. Thus, intracellular cytokine signalling may serve as 'fate determinants' used by HSPCs to modulate their activity.
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http://dx.doi.org/10.1038/ncomms14382 | DOI Listing |
Adv Sci (Weinh)
January 2025
Department for Functional Materials in Medicine and Dentistry, University Hospital Würzburg, Würzburg, Germany.
Studying the molecular basis of intestinal infections caused by enteric pathogens at the tissue level is challenging, because most human intestinal infection models have limitations, and results obtained from animals may not reflect the human situation. Infections with Salmonella enterica serovar Typhimurium (STm) have different outcomes between organisms. 3D tissue modeling of primary human material provides alternatives to animal experimentation, but epithelial co-culture with immune cells remains difficult.
View Article and Find Full Text PDFActa Pharm Sin B
December 2024
Department of Molecular and Life Science, Hanyang University, Ansan 15588, Republic of Korea.
The pathophysiology of sepsis is characterized by a systemic inflammatory response to infection; however, the cytokine blockade that targets a specific early inflammatory mediator, such as tumor necrosis factor, has shown disappointing results in clinical trials. During sepsis, excessive endotoxins are internalized into the cytoplasm of immune cells, resulting in dysregulated pyroptotic cell death, which induces the leakage of late mediator alarmins such as HMGB1 and PTX3. As late mediators of lethal sepsis, overwhelming amounts of alarmins bind to high-affinity TLR4/MD2 and low-affinity RAGE receptors, thereby amplifying inflammation during early-stage sepsis.
View Article and Find Full Text PDFCurr Mol Pharmacol
January 2025
Área Académica de Medicina del Instituto de Ciencias de la Salud, Universidad Autónoma del Estado de Hidalgo, Pachuca, Hidalgo, México.
Introduction: This work aimed to evaluate the anti-inflammatory and myorelaxant effect of thymol (TM) and carvacrol (CAR) in the pregnant rat uterus. Both compounds exhibit considerable antimicrobial, antispasmodic, and anti-inflammatory effects and due to these properties, they were studied in this in vitro model of premature birth induced by infection.
Method: All uterine tissues were studied in uterine contraction tests to determine the inhibitory effect of TM, CAR (10, 56, 100, 150, and 230 μM), and nifedipine (a calcium channel antagonist) on phasic and tonic contraction induced by electro- and pharmacomechanical stimuli.
Microb Pathog
January 2025
Institute of Pathogenic Biology, Hengyang Medical College, University of South China, Hengyang 421001, Hunan, China. Electronic address:
Mycoplasma pneumoniae (M. pneumoniae) is one of the major pathogens causing community-acquired pneumonia (CAP), and its pathogenic mechanism is not fully understood. Inflammatory response is the most basic and common pathological phenomenon of CAP, but the specific mechanism needs further investigation.
View Article and Find Full Text PDFTransplant Direct
February 2025
Department of Surgery, Comprehensive Transplant Center, and the College of Medicine, The Ohio State University, Columbus, OH.
Background: Alloprimed antibody-suppressor CXCR5CD8 T cells (CD8 T cells) downregulate alloantibody production, mediate cytotoxicity of IgG B cells, and prolong allograft survival. The purpose of this investigation was to determine which immune-cell subsets are susceptible to CD8 T cell-mediated cytotoxicity or noncytotoxic suppression.
Methods: Alloprimed immune-cell subsets were evaluated for susceptibility to CD8 T cell-mediated in vitro cytotoxicity and/or suppression of intracellular cytokine expression.
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