Research Article
Abstract
Acute megakaryoblastic leukemia of Down syndrome (DS-AMKL) is a model of clonal evolution from a preleukemic transient myeloproliferative disorder requiring both a trisomy 21 (T21) and a GATA1s mutation to a leukemia driven by additional driver mutations. We modeled the megakaryocyte differentiation defect through stepwise gene editing of GATA1s, SMC3+/–, and MPLW515K, providing 20 different T21 or disomy 21 (D21) induced pluripotent stem cell (iPSC) clones. GATA1s profoundly reshaped iPSC-derived hematopoietic architecture with gradual myeloid-to-megakaryocyte shift and megakaryocyte differentiation alteration upon addition of SMC3 and MPL mutations. Transcriptional, chromatin accessibility, and GATA1-binding data showed alteration of essential megakaryocyte differentiation genes, including NFE2 downregulation that was associated with loss of GATA1s binding and functionally involved in megakaryocyte differentiation blockage. T21 enhanced the proliferative phenotype, reproducing the cellular and molecular abnormalities of DS-AMKL. Our study provides an array of human cell–based models revealing individual contributions of different mutations to DS-AMKL differentiation blockage, a major determinant of leukemic progression.
Authors
Brahim Arkoun, Elie Robert, Fabien Boudia, Stefania Mazzi, Virginie Dufour, Aurélie Siret, Yasmine Mammasse, Zakia Aid, Matthieu Vieira, Imanci Aygun, Marine Aglave, Marie Cambot, Rachel Petermann, Sylvie Souquere, Philippe Rameau, Cyril Catelain, Romain Diot, Gérard Tachdjian, Olivier Hermine, Nathalie Droin, Najet Debili, Isabelle Plo, Sébastien Malinge, Eric Soler, Hana Raslova, Thomas Mercher, William Vainchenker
Abstract
Human pluripotent stem cell–based (hPSC-based) replacement therapy holds great promise for the treatment of Parkinson’s disease (PD). However, the heterogeneity of hPSC-derived donor cells and the low yield of midbrain dopaminergic (mDA) neurons after transplantation hinder its broad clinical application. Here, we have characterized the single-cell molecular landscape during mDA neuron differentiation. We found that this process recapitulated the development of multiple but adjacent fetal brain regions including the ventral midbrain, the isthmus, and the ventral hindbrain, resulting in a heterogenous donor cell population. We reconstructed the differentiation trajectory of the mDA lineage and identified calsyntenin 2 (CLSTN2) and protein tyrosine phosphatase receptor type O (PTPRO) as specific surface markers of mDA progenitors, which were predictive of mDA neuron differentiation and could facilitate high enrichment of mDA neurons (up to 80%) following progenitor cell sorting and transplantation. Marker-sorted progenitors exhibited higher therapeutic potency in correcting motor deficits of PD mice. Different marker-sorted grafts had a strikingly consistent cellular composition, in which mDA neurons were enriched, while off-target neuron types were mostly depleted, suggesting stable graft outcomes. Our study provides a better understanding of cellular heterogeneity during mDA neuron differentiation and establishes a strategy to generate highly purified donor cells to achieve stable and predictable therapeutic outcomes, raising the prospect of hPSC-based PD cell replacement therapies.
Authors
Peibo Xu, Hui He, Qinqin Gao, Yingying Zhou, Ziyan Wu, Xiao Zhang, Linyu Sun, Gang Hu, Qian Guan, Zhiwen You, Xinyue Zhang, Wenping Zheng, Man Xiong, Yuejun Chen
Abstract
Primary graft dysfunction (PGD) is the leading cause of postoperative mortality in lung transplant recipients and the most important risk factor for development of chronic lung allograft dysfunction. The mechanistic basis for the variability in the incidence and severity of PGD between lung transplant recipients is not known. Using a murine orthotopic vascularized lung transplant model, we found that redundant activation of Toll-like receptors 2 and 4 (TLR2 and -4) on nonclassical monocytes activates MyD88, inducing the release of the neutrophil attractant chemokine CXCL2. Deletion of Itgam (encodes CD11b) in nonclassical monocytes enhanced their production of CXCL2 and worsened PGD, while a CD11b agonist, leukadherin-1, administered only to the donor lung prior to lung transplantation, abrogated CXCL2 production and PGD. The damage-associated molecular pattern molecule HMGB1 was increased in peripheral blood samples from patients undergoing lung transplantation after reperfusion and induced CXCL2 production in nonclassical monocytes via TLR4/MyD88. An inhibitor of HMGB1 administered to the donor and recipient prior to lung transplantation attenuated PGD. Our findings suggest that CD11b acts as a molecular brake to prevent neutrophil recruitment by nonclassical monocytes following lung transplantation, revealing an attractive therapeutic target in the donor lung to prevent PGD in lung transplant recipients.
Authors
Melissa Querrey, Stephen Chiu, Emilia Lecuona, Qiang Wu, Haiying Sun, Megan Anderson, Megan Kelly, Sowmya Ravi, Alexander V. Misharin, Daniel Kreisel, Ankit Bharat, G.R. Scott Budinger
Abstract
The metabolic dependencies of cancer cells have substantial potential to be exploited to improve the diagnosis and treatment of cancer. Creatine riboside (CR) is identified as a urinary metabolite associated with risk and prognosis in lung and liver cancer. However, the source of high CR levels in patients with cancer as well as their implications for the treatment of these aggressive cancers remain unclear. By integrating multiomics data on lung and liver cancer, we have shown that CR is a cancer cell–derived metabolite. Global metabolomics and gene expression analysis of human tumors and matched liquid biopsies, together with functional studies, revealed that dysregulation of the mitochondrial urea cycle and a nucleotide imbalance were associated with high CR levels and indicators of a poor prognosis. This metabolic phenotype was associated with reduced immune infiltration and supported rapid cancer cell proliferation that drove aggressive tumor growth. CRhi cancer cells were auxotrophic for arginine, revealing a metabolic vulnerability that may be exploited therapeutically. This highlights the potential of CR not only as a poor-prognosis biomarker but also as a companion biomarker to inform the administration of arginine-targeted therapies in precision medicine strategies to improve survival for patients with cancer.
Authors
Amelia L. Parker, Leila Toulabi, Takahiro Oike, Yasuyuki Kanke, Daxeshkumar Patel, Takeshi Tada, Sheryse Taylor, Jessica A. Beck, Elise Bowman, Michelle L. Reyzer, Donna Butcher, Skyler Kuhn, Gary T. Pauly, Kristopher W. Krausz, Frank J. Gonzalez, S. Perwez Hussain, Stefan Ambs, Bríd M. Ryan, Xin Wei Wang, Curtis C. Harris
Abstract
Intrahepatic neutrophil infiltration has been implicated in severe alcoholic hepatitis (SAH) pathogenesis; however, the mechanism underlying neutrophil-induced injury in SAH remains obscure. This translational study aims to describe the patterns of intrahepatic neutrophil infiltration and its involvement in SAH pathogenesis. Immunohistochemistry analyses of explanted livers identified two SAH phenotypes despite a similar clinical presentation, one with high intrahepatic neutrophils (Neuhi), but low levels of CD8+ T cells, and vice versa. RNA-Seq analyses demonstrated that neutrophil cytosolic factor 1 (NCF1), a key factor in controlling neutrophilic ROS production, was upregulated and correlated with hepatic inflammation and disease progression. To study specifically the mechanisms related to Neuhi in AH patients and liver injury, we used the mouse model of chronic-plus-binge ethanol feeding and found that myeloid-specific deletion of the Ncf1 gene abolished ethanol-induced hepatic inflammation and steatosis. RNA-Seq analysis and the data from experimental models revealed that neutrophilic NCF1-dependent ROS promoted alcoholic hepatitis (AH) by inhibiting AMP-activated protein kinase (a key regulator of lipid metabolism) and microRNA-223 (a key antiinflammatory and antifibrotic microRNA). In conclusion, two distinct histopathological phenotypes based on liver immune phenotyping are observed in SAH patients, suggesting a separate mechanism driving liver injury and/or failure in these patients.
Authors
Jing Ma, Adrien Guillot, Zhihong Yang, Bryan Mackowiak, Seonghwan Hwang, Ogyi Park, Brandon J. Peiffer, Ali Reza Ahmadi, Luma Melo, Praveen Kusumanchi, Nazmul Huda, Romil Saxena, Yong He, Yukun Guan, Dechun Feng, Pau Sancho-Bru, Mengwei Zang, Andrew MacGregor Cameron, Ramon Bataller, Frank Tacke, Zhaoli Sun, Suthat Liangpunsakul, Bin Gao
Abstract
Charcot-Marie-Tooth disease type 1A (CMT1A), the most common inherited demyelinating peripheral neuropathy, is caused by PMP22 gene duplication. Overexpression of WT PMP22 in Schwann cells destabilizes the myelin sheath, leading to demyelination and ultimately to secondary axonal loss and disability. No treatments currently exist that modify the disease course. The most direct route to CMT1A therapy will involve reducing PMP22 to normal levels. To accomplish this, we developed a gene therapy strategy to reduce PMP22 using artificial miRNAs targeting human PMP22 and mouse Pmp22 mRNAs. Our lead therapeutic miRNA, miR871, was packaged into an adeno-associated virus 9 (AAV9) vector and delivered by lumbar intrathecal injection into C61-het mice, a model of CMT1A. AAV9-miR871 efficiently transduced Schwann cells in C61-het peripheral nerves and reduced human and mouse PMP22 mRNA and protein levels. Treatment at early and late stages of the disease significantly improved multiple functional outcome measures and nerve conduction velocities. Furthermore, myelin pathology in lumbar roots and femoral motor nerves was ameliorated. The treated mice also showed reductions in circulating biomarkers of CMT1A. Taken together, our data demonstrate that AAV9-miR871–driven silencing of PMP22 rescues a CMT1A model and provides proof of principle for treating CMT1A using a translatable gene therapy approach.
Authors
Marina Stavrou, Alexia Kagiava, Sarah G. Choudury, Matthew J. Jennings, Lindsay M. Wallace, Allison M. Fowler, Amanda Heslegrave, Jan Richter, Christina Tryfonos, Christina Christodoulou, Henrik Zetterberg, Rita Horvath, Scott Q. Harper, Kleopas A. Kleopa
Abstract
In lymphopenic environments, secondary lymphoid organs regulate the size of B and T cell compartments by supporting the homeostatic proliferation of mature lymphocytes. The molecular mechanisms underlying these responses and their functional consequences remain incompletely understood. To evaluate homeostasis of the mature B cell pool during lymphopenia, we turned to an adoptive transfer model of purified follicular B cells into Rag2–/– mouse recipients. Highly purified follicular B cells transdifferentiated into marginal zone–like B cells when transferred into Rag2–/– lymphopenic hosts but not into wild-type hosts. In lymphopenic spleens, transferred B cells gradually lost their follicular phenotype and acquired characteristics of marginal zone B cells, as judged by cell surface phenotype, expression of integrins and chemokine receptors, positioning close to the marginal sinus, and an ability to rapidly generate functional plasma cells. Initiation of follicular to marginal zone B cell transdifferentiation preceded proliferation. Furthermore, the transdifferentiation process was dependent on Notch2 receptors in B cells and expression of Delta-like 1 Notch ligands by splenic Ccl19-Cre+ fibroblastic stromal cells. Gene expression analysis showed rapid induction of Notch-regulated transcripts followed by upregulated Myc expression and acquisition of broad transcriptional features of marginal zone B cells. Thus, naive mature B cells are endowed with plastic transdifferentiation potential in response to increased stromal Notch ligand availability during lymphopenia.
Authors
Daniela Gómez Atria, Brian T. Gaudette, Jennifer Londregan, Samantha Kelly, Eric Perkey, Anneka Allman, Bhaskar Srivastava, Ute Koch, Freddy Radtke, Burkhard Ludewig, Christian W. Siebel, Russell J.H. Ryan, Tanner F. Robertson, Janis K. Burkhardt, Warren S. Pear, David Allman, Ivan Maillard
Abstract
Mitochondrial proteostasis, regulated by the mitochondrial unfolded protein response (UPRmt), is crucial for maintenance of cellular functions and survival. Elevated oxidative and proteotoxic stress in mitochondria must be attenuated by the activation of a ubiquitous UPRmt to promote prostate cancer (PCa) growth. Here we show that the 2 key components of the UPRmt, heat shock protein 60 (HSP60, a mitochondrial chaperonin) and caseinolytic protease P (ClpP, a mitochondrial protease), were required for the development of advanced PCa. HSP60 regulated ClpP expression via c-Myc and physically interacted with ClpP to restore mitochondrial functions that promote cancer cell survival. HSP60 maintained the ATP-producing functions of mitochondria, which activated the β-catenin pathway and led to the upregulation of c-Myc. We identified a UPRmt inhibitor that blocked HSP60’s interaction with ClpP and abrogated survival signaling without altering HSP60’s chaperonin function. Disruption of HSP60-ClpP interaction with the UPRmt inhibitor triggered metabolic stress and impeded PCa-promoting signaling. Treatment with the UPRmt inhibitor or genetic ablation of Hsp60 inhibited PCa growth and progression. Together, our findings demonstrate that the HSP60-ClpP–mediated UPRmt is essential for prostate tumorigenesis and the HSP60-ClpP interaction represents a therapeutic vulnerability in PCa.
Authors
Rahul Kumar, Ajay K. Chaudhary, Jordan Woytash, Joseph R. Inigo, Abhiram A. Gokhale, Wiam Bshara, Kristopher Attwood, Jianmin Wang, Joseph A. Spernyak, Eva Rath, Neelu Yadav, Dirk Haller, David W. Goodrich, Dean G. Tang, Dhyan Chandra
Abstract
Constant exposure of the airways to inhaled pathogens requires efficient early immune responses protecting against infections. How bacteria on the epithelial surface are detected and first-line protective mechanisms are initiated are not well understood. We have recently shown that tracheal brush cells (BCs) express functional taste receptors. Here we report that bitter taste signaling in murine BCs induces neurogenic inflammation. We demonstrate that BC signaling stimulates adjacent sensory nerve endings in the trachea to release the neuropeptides CGRP and substance P that mediate plasma extravasation, neutrophil recruitment, and diapedesis. Moreover, we show that bitter tasting quorum-sensing molecules from Pseudomonas aeruginosa activate tracheal BCs. BC signaling depends on the key taste transduction gene Trpm5, triggers secretion of immune mediators, among them the most abundant member of the complement system, and is needed to combat P. aeruginosa infections. Our data provide functional insight into first-line defense mechanisms against bacterial infections of the lung.
Authors
Monika I. Hollenhorst, Rajender Nandigama, Saskia B. Evers, Igor Gamayun, Noran Abdel Wadood, Alaa Salah, Mario Pieper, Amanda Wyatt, Alexey Stukalov, Anna Gebhardt, Wiebke Nadolni, Wera Burow, Christian Herr, Christoph Beisswenger, Soumya Kusumakshi, Fabien Ectors, Tatjana I. Kichko, Lisa Hübner, Peter Reeh, Antje Munder, Sandra-Maria Wienhold, Martin Witzenrath, Robert Bals, Veit Flockerzi, Thomas Gudermann, Markus Bischoff, Peter Lipp, Susanna Zierler, Vladimir Chubanov, Andreas Pichlmair, Peter König, Ulrich Boehm, Gabriela Krasteva-Christ
Abstract
DNA methyltransferase 3a (DNMT3a) is an important part of the epigenetic machinery that stabilizes patterns of activated T cell responses. We hypothesized that donor T cell DNMT3a regulates alloreactivity after allogeneic blood and marrow transplantation (allo-BMT). T cell conditional Dnmt3a KO mice were used as donors in allo-BMT models. Mice receiving allo-BMT from KO donors developed severe acute graft-versus-host disease (aGVHD), with increases in inflammatory cytokine levels and organ histopathology scores. KO T cells migrated and proliferated in secondary lymphoid organs earlier and demonstrated an advantage in trafficking to the small intestine. Donor T cell subsets were purified after BMT for whole-genome bisulfite sequencing (WGBS) and RNA-Seq. KO T cells had global methylation similar to that of WT cells, with distinct, localized areas of hypomethylation. Using a highly sensitive computational method, we produced a comprehensive profile of the altered epigenome landscape. Hypomethylation corresponded with changes in gene expression in several pathways of T cell signaling and differentiation. Additionally, Dnmt3a-KO T cells resulted in superior graft-versus-tumor activity. Our findings demonstrate a critical role for DNMT3a in regulating T cell alloreactivity and reveal pathways that control T cell tolerance. These results also provide a platform for deciphering clinical data that associate donor DNMT3a mutations with increased GVHD, decreased relapse, and improved survival.
Authors
Yiouli P. Ktena, Michael A. Koldobskiy, Michael I. Barbato, Han-Hsuan Fu, Leo Luznik, Nicolas J. Llosa, Azeb Haile, Orly R. Klein, Chen Liu, Christopher J. Gamper, Kenneth R. Cooke
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ISSN: 0021-9738 (print), 1558-8238 (online)