Stem cells
Abstract
Defining mechanism(s) that maintain tissue stem quiescence is important for improving tissue regeneration, cell therapies, aging, and cancer. We report here that genetic ablation of Id2 in adult hematopoietic stem cells (HSCs) promotes increased HSC activation and differentiation, which results in HSC exhaustion and bone marrow failure over time. Id2Δ/Δ HSCs showed increased cycling, ROS production, mitochondrial activation, ATP production, and DNA damage compared with Id2+/+ HSCs, supporting the conclusion that Id2Δ/Δ HSCs are less quiescent. Mechanistically, HIF-1α expression was decreased in Id2Δ/Δ HSCs, and stabilization of HIF-1α in Id2Δ/Δ HSCs restored HSC quiescence and rescued HSC exhaustion. Inhibitor of DNA binding 2 (ID2) promoted HIF-1α expression by binding to the von Hippel-Lindau (VHL) protein and interfering with proteasomal degradation of HIF-1α. HIF-1α promoted Id2 expression and enforced a positive feedback loop between ID2 and HIF-1α to maintain HSC quiescence. Thus, sustained ID2 expression could protect HSCs during stress and improve HSC expansion for gene editing and cell therapies.
Authors
Brad L. Jakubison, Tanmoy Sarkar, Kristbjorn O. Gudmundsson, Shweta Singh, Lei Sun, Holly M. Morris, Kimberly D. Klarmann, Jonathan R. Keller
Abstract
Human pluripotent stem cell (hPSC)-based replacement therapy holds great promise in treating 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 depicted 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 ventral midbrain, isthmus, and ventral hindbrain, resulting in heterogenous donor cell population. We reconstructed the differentiation trajectory of mDA lineage and identified CLSTN2 and PTPRO as specific surface markers of mDA progenitors, which were predictive of mDA neuron differentiation and could facilitate highly enriched mDA neurons (up to 80%) following progenitor 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
Fanconi Anemia (FA) is the most prevalent inherited bone marrow failure (BMF) syndrome. Nevertheless, the pathophysiological mechanisms of BMF in FA have not been fully elucidated. Since FA cells are defective in DNA repair, we hypothesized that FA hematopoietic stem and progenitor cells (HSPCs) might express DNA damage-associated stress molecules such as Natural Killer group 2 member D ligands (NKG2D-Ls). These ligands could then interact with the activating NKG2D receptor expressed in cytotoxic NK or CD8+ T cells which may result in progressive HSPCs depletion. Our results indeed demonstrated upregulated levels of NKG2D-Ls in cultured FA fibroblasts and T cells, which were further exacerbated by mitomycin C or formaldehyde. Notably, a high proportion of BM CD34+ HSPCs from FA patients also expressed increased levels of NKG2D-Ls, which correlated inversely with the percentage of CD34+ cells in BM. Remarkably, the reduced clonogenic potential characteristic of FA HSPCs was improved by blocking NKG2D/NKG2D-L interactions. Moreover, the in vivo blockage of these interactions in a BMF FA mouse model ameliorated the anemia in these animals. Our study demonstrates the involvement of NKG2D/NKG2D-L interactions in FA HSPC functionality, suggesting an unexpected role of the immune system in the progressive BMF characteristic of FA.
Authors
Jose A. Casado, Antonio Valeri, Rebeca Sanchez-Domínguez, Paula Vela, Andrea Lopez, Susana Navarro, Omaira Alberquilla, Helmut Hanenberg, Roser Pujol, Jose C. Segovia, Jordi Minguillón, Jordi Surrallés, Cristina Diaz-de-Heredia, Julián Sevilla, Paula Rio, Juan A. Bueren
Abstract
Fibrodysplasia ossificans progressiva (FOP) is a rare genetic disease characterized by progressive and catastrophic heterotopic ossification (HO) of skeletal muscle and associated soft tissues. FOP is caused by dominantly acting mutations in the gene encoding the bone morphogenetic protein (BMP) type I receptor, ACVR1 (ALK2), the most prevalent of which results in an arginine to histidine substitution at position 206[ACVR1(R206H)]. The fundamental pathological consequence of FOP-causing ACVR1 receptor mutations is to enable activin A to initiate canonical BMP signaling in fibro-adipogenic progenitors (FAPs), which drives HO. We developed a monoclonal blocking antibody (JAB0505) to the extracellular domain of ACVR1 and tested its effect on HO in two independent FOP mouse models. Although JAB0505 inhibited BMP-dependent gene expression in wild-type and ACVR1(R206H)-overexpressing cell lines, JAB0505 treatment profoundly exacerbated injury-induced HO. JAB0505-treated mice exhibited multiple, distinct foci of heterotopic lesions, suggesting an atypically broad anatomical domain of FAP recruitment to endochondral ossification. This was accompanied by dysregulated FAP population growth and an abnormally sustained immunological reaction following muscle injury. JAB0505 drove injury-induced HO in the absence of activin A, indicating that JAB0505 has receptor agonist activity. These data raise serious safety and efficacy concerns for the use of bivalent anti-ACVR1 antibodies to treat patients with FOP.
Authors
John B. Lees-Shepard, Sean J. Stoessel, Julian T. Chandler, Keith Bouchard, Patricia Bento, Lorraine N. Apuzzo, Parvathi Madhavi Devarakonda, Jeffrey W. Hunter, David J. Goldhamer
Abstract
Once human photoreceptors die, they do not regenerate, thus photoreceptor transplantation has emerged as a potential treatment approach for blinding diseases. Improvements in transplant organization, donor cell maturation and synaptic connectivity to the host will be critical in advancing this technology to clinical practice. Unlike the unstructured grafts of prior cell suspension transplantations into end-stage degeneration models, we describe extensive incorporation of iPSC retinal organoid-derived human photoreceptors into mice with cone dysfunction. This incorporative phenotype was validated in both cone-only as well as pan-photoreceptor transplantations. Rather than forming a glial barrier, Müller cells extended throughout the graft, even forming a series of adherens junctions between mouse and human cells, reminiscent of an outer limiting membrane. Donor-host interaction appeared to promote polarisation as well as development of morphological features critical for light detection, namely formation of inner and well stacked outer segments oriented towards the retinal pigment epithelium. Putative synapse formation and graft function was evident both at a structural and electrophysiological level. Overall, these results show that human photoreceptors interact readily with a partially degenerated retina. Moreover, incorporation into the host retina appears to be beneficial to graft maturation, polarisation and function.
Authors
Sylvia J. Gasparini, Karen Tessmer, Miriam Reh, Stephanie Wieneke, Madalena Carido, Manuela Völkner, Oliver Borsch, Anka Swiersy, Marta Zuzic, Olivier Goureau, Thomas Kurth, Volker Busskamp, Günther Zeck, Mike O. Karl, Marius Ader
Abstract
AbstractType 2 alveolar epithelial cells (AEC2s) function as progenitor cells in the lung. We have shown previously that failure of AEC2 regeneration results in progressive lung fibrosis in mice and is a cardinal feature of idiopathic pulmonary fibrosis (IPF). In this study, we identified a deficiency of a specific zinc transporter SLC39A8 (ZIP8) in AEC2s from both IPF lungs and lungs of old mice. Loss of ZIP8 expression was associated with impaired renewal capacity of AEC2s and enhanced lung fibrosis. ZIP8 regulation of AEC2 progenitor function was dependent on SIRT1. Replenishment with exogenous zinc and SIRT1 activation promoted self-renewal and differentiation of AEC2s from lung tissues of IPF patients and old mice. Deletion of Zip8 in AEC2s in mice impaired AEC2 renewal, increased susceptibility of the mice to bleomycin injury, and the mice developed spontaneous lung fibrosis. Therapeutic strategies to restore zinc metabolism and appropriate SIRT1 signaling could improve AEC2 progenitor function and mitigate ongoing fibrogenesis.
Authors
Jiurong Liang, Guanling Huang, Xue Liu, Forough Taghavifar, Ningshan Liu, Yizhou Wang, Nan Deng, Changfu Yao, Ting Xie, Vrishika Kulur, Kristy Dai, Ankita Burman, Simon C. Rowan, S. Samuel Weigt, John Belperio, Barry Stripp, William C. Parks, Dianhua Jiang, Paul W. Noble
Abstract
BACKGROUND. Responses to conventional donor lymphocyte infusion (DLI) for post-allogeneic hematopoietic cell transplantation (HCT) relapse are typically poor. Natural killer (NK) cell-based therapy is a promising modality to treat post-HCT relapse. METHODS. We initiated this ongoing phase I trial of adoptively transferred cytokine induced memory-like (CIML) NK cells in patients with myeloid malignancies relapsed after haploidentical HCT. All patients received a donor-derived NK cell dose of 5–10 million cells/kg after lymphodepleting chemotherapy, followed by systemic IL-2 for 7 doses. High resolution profiling with mass cytometry and single cell RNA sequencing characterized the expanding and persistent NK cell subpopulations in a longitudinal manner after infusion. RESULTS. In the first 6 enrolled patients on the trial, infusion of CIML NK cells led to a rapid 10 to 50-fold in vivo expansion that was sustained over months. The infusion was well-tolerated, with fever and pancytopenia as the most common adverse events. Expansion of NK cells was distinct from IL-2 effects on endogenous post-HCT NK cells, and not dependent on CMV viremia. Immunophenotypic and transcriptional profiling revealed a dynamic evolution of the activated CIML NK cell phenotype, superimposed on the natural variation in donor NK cell repertoires. CONCLUSION. Given their rapid expansion and long-term persistence in an immune compatible environment, CIML NK cells serve as a promising platform for the treatment of post-transplant relapse of myeloid disease. Further characterization of their unique in vivo biology and interaction with both T cells and tumor targets will lead to improvements in cell-based immunotherapies. TRIAL REGISTRATION. NCT04024761 FUNDING. Supported by Dunkin Donuts Breakthrough Award, the NIH/National Cancer Institute R21 CA245413, the Leukemia and Lymphoma Society Scholar and TRP awards.
Authors
Roman M. Shapiro, Grace C. Birch, Guangan Hu, Juliana Vergara Cadavid, Sarah Nikiforow, Joanna Baginska, Alaa K. Ali, Mubin Tarannum, Michal Sheffer, Yasmin Z. Abdulhamid, Benedetta Rambaldi, Yohei Arihara, Carol Reynolds, Max S. Halpern, Scott J. Rodig, Nicole Cullen, Jacquelyn O. Wolff, Kathleen L. Pfaff, Andrew A. Lane, R. Coleman Lindsley, Corey S. Cutler, Joseph H. Antin, Vincent T. Ho, John Koreth, Mahasweta Gooptu, Haesook T. Kim, Karl-Johan Malmberg, Catherine J. Wu, Jianzhu Chen, Robert J. Soiffer, Jerome Ritz, Rizwan Romee
Abstract
Platelets have a wide range of functions including critical roles in hemostasis, thrombosis, and immunity. We hypothesized that during acute inflammation, such as in life-threatening sepsis, there are fundamental changes in the sites of platelet production and phenotypes of resultant platelets. Here, we showed during sepsis that the spleen is a major site of megakaryopoiesis and platelet production. Sepsis provoked an adrenergic-dependent mobilization of megakaryocyte-erythrocyte progenitors (MEPs) from the bone marrow to the spleen where interleukin-3 (IL-3) induced their differentiation into megakaryocytes. In the spleen, immune-skewed megakaryocytes produced a CD40 ligand-high platelet population with potent immunomodulatory functions. Transfusions of post-sepsis platelets enriched from splenic production enhanced immune responses and reduced overall mortality in sepsis-challenged animals. These findings identify a spleen-derived protective platelet population that may be broadly immunomodulatory in acute inflammatory states such as sepsis.
Authors
Colin Valet, Mélia Magnen, Longhui Qiu, Simon J. Cleary, Kristin M. Wang, Serena Ranucci, Elodie Grockowiak, Rafik Boudra, Catharina Conrad, Yurim Seo, Daniel R. Calabrese, John R. Greenland, Andrew D. Leavitt, Emmanuelle Passegué, Simon Mendez-Ferrer, Filip K. Swirski, Mark R. Looney
Abstract
Glioblastoma (GBM) is the most common and lethal primary malignant brain tumor, containing GBM stem cells (GSCs) that contribute to therapeutic resistance and relapse. Exposing potential GSC vulnerabilities may provide therapeutic strategies against GBM. Here, we interrogated the role of Adenosine-to-Inosine (A-to-I) RNA editing mediated by ADAR1 (adenosine deaminase acting on RNA 1) in GSCs and found that both ADAR1 and global RNA editomes were elevated in GSCs compared to normal neural stem cells (NSCs). ADAR1 inactivation or blocking the upstream JAK/STAT pathway through TYK2 inhibition impaired GSC self-renewal and stemness. Downstream of ADAR1, RNA editing of the 3’UTR of GM2A, a key ganglioside catabolism activator, proved to be critical, as interfering with ganglioside catabolism showed similar functional impact on GSCs as ADAR1 disruption. These findings reveal RNA editing links ganglioside catabolism to GSC self-renewal and stemness, exposing a potential vulnerability of GBM for therapeutic intervention.
Authors
Li Jiang, Yajing Hao, Changwei Shao, Qiulian Wu, Briana C. Prager, Ryan C. Gimple, Gabriele Sulli, Leo J.K. Kim, Guoxin Zhang, Zhixin Qiu, Zhe Zhu, Xiang-Dong Fu, Jeremy N. Rich
Abstract
Human pluripotent stem cells (hPSCs) hold great promise for the treatment of various human diseases. However, their therapeutic benefits and mechanisms for treating corneal endothelial dysfunction remain undefined. Here, we developed a therapeutic regimen consisting of the combination of hPSC-derived corneal endothelial precursors (CEPs) with nicotinamide (NAM) for effective treatment of corneal endothelial dysfunction. In rabbit and nonhuman primate models, intracameral injection of CEPs and NAM achieved long-term recovery of corneal clarity and thickness, similar with the therapeutic outcome of cultured human corneal endothelial cells (CECs). The transplanted human CEPs exhibited structural and functional integration with host resident CECs. However, the long-term recovery relied on the stimulation of endogenous endothelial regeneration in rabbits, but predominantly on the replacing function of transplanted cells during the 3-year follow-up in nonhuman primates, which resemble human corneal endothelium with limited regenerative capacity. Mechanistically, NAM ensured in vivo proper maturation of transplanted CEPs into functional CECs by preventing premature senescence and endothelial-mesenchymal transition within the TGF-β–enriched aqueous humor. Together, we provide compelling experimental evidence and mechanistic insights of simultaneous delivery of CEPs and NAM as a potential approach for treating corneal endothelial dysfunction.
Authors
Zongyi Li, Haoyun Duan, Yanni Jia, Can Zhao, Wenjing Li, Xin Wang, Yajie Gong, Chunxiao Dong, Bochao Ma, Shengqian Dou, Bin Zhang, Dongfang Li, Yihai Cao, Lixin Xie, Qingjun Zhou, Weiyun Shi
Copyright © 2025 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)