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Dual targeting macrophages and microglia is a therapeutic vulnerability in models of PTEN-deficient glioblastoma

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Abstract

Tumor-associated macrophages and microglia (TAMs) are critical for tumor progression and therapy resistance in glioblastoma (GBM), a type of incurable brain cancer. We previously identified lysyl oxidase (LOX) and olfactomedin like-3 (OLFML3) as essential macrophage and microglia chemokines, respectively, in GBM. Here, single-cell transcriptomics and multiplex sequential immunofluorescence followed by functional studies demonstrate that macrophages negatively correlate with microglia in the GBM tumor microenvironment. LOX inhibition in PTEN-deficient GBM cells upregulates OLFML3 expression via the NF-κB-PATZ1 signaling pathway, inducing a compensatory increase of microglia infiltration. Dual targeting macrophages and microglia via inhibition of LOX and the CLOCK-OLFML3 axis generates potent anti-tumor effects and offers a complete tumor regression in more than 60% of animals when combined with anti-PD1 therapy in PTEN-deficient GBM mouse models. Thus, our findings provide a translational triple therapeutic strategy for this lethal disease.

Authors

Yang Liu, Junyan Wu, Hinda Najem, Yiyun Lin, Lizhi Pang, Fatima Khan, Fei Zhou, Heba Ali, Amy B. Heimberger, Peiwen Chen

Neuropilin-2 expressing cells in breast cancer are S-nitrosylation hubs that mitigate radiation-induced oxidative stress

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Abstract

The high rate of recurrence after radiation therapy in triple-negative breast cancer (TNBC) indicates that novel approaches and targets are needed to enhance radiosensitivity. Here, we report that neuropilin-2 (NRP2), a receptor for vascular endothelial growth factor (VEGF) that is enriched on sub-populations of TNBC cells with stem cell properties, is an effective therapeutic target for sensitizing TNBC to radiotherapy. Specifically, VEGF/NRP2 signaling induces nitric oxide synthase 2 (NOS2) transcription by a mechanism dependent on Gli1. NRP2-expressing tumor cells serve as a hub to produce nitric oxide (NO), an autocrine and paracrine signaling metabolite, which promotes cysteine-nitrosylation of Kelch-like ECH-asssociated protein 1 (KEAP1) and, consequently, nuclear factor erythroid 2-related factor 2 (NFE2L2)-mediated transcription of antioxidant response genes. Inhibiting VEGF binding to NRP2, using a humanized monoclonal antibody (mAb), results in NFE2L2 degradation via KEAP1 rendering cell lines and organoids vulnerable to irradiation. Importantly, treatment of patient-derived xenografts with the NRP2 mAb and radiation resulted in significant tumor necrosis and regression compared to radiation alone. Together, these findings reveal a targetable mechanism of radioresistance and they support the use of NRP2 mAb as an effective radiosensitizer in TNBC.

Authors

Ayush Kumar, Hira Goel, Christi Wisniewski, Tao Wang, Yansong Geng, Mengdie Wang, Shivam Goel, Kai Hu, Rui Li, Lihua J. Zhu, Jennifer L. Clark, Lindsay M. Ferreira, Michael Brehm, Thomas J. Fitzgerald, Arthur M. Mercurio

YTHDF1 loss in dendritic cells potentiates radiation-induced antitumor immunity via STING-dependent type I IFN production

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Abstract

RNA N6-methyladenosine (m6A) reader YTHDF1 is implicated in cancer etiology and progression. We discovered that radiotherapy (RT) increased YTHDF1 expression in dendritic cells (DCs) of PBMCs from cancer patients, but not in other immune cells tested. Elevated YTHDF1 expression of DCs was associated with poor outcomes in patients receiving RT. We found that loss of Ythdf1 in DCs enhanced the antitumor effects of ionizing radiation (IR) via increasing the cross-priming capacity of DCs across multiple murine cancer models. Mechanistically, IR upregulated YTHDF1 expression in DCs through STING-IFN-I signaling. YTHDF1 in turn triggered STING degradation by increasing lysosomal cathepsins, thereby reducing IFN-I production. We created a YTHDF1 deletion/inhibition prototype DC vaccine, significantly improving the therapeutic effect of RT and radio-immunotherapy in a murine melanoma model. Our findings reveal a new layer of regulation between YTHDF1/m6A and STING in response to IR, which opens new paths for the development of YTHDF1-targeting therapies.

Authors

Chuangyu Wen, Liangliang Wang, András Piffkó, Dapeng Chen, Xianbin Yu, Katarzyna Zawieracz, Jason Bugno, Kaiting Yang, Emile Z. Naccasha, Fei Ji, Jiaai Wang, Xiaona Huang, Stephen Y. Luo, Lei Tan, Bin Shen, Cheng Luo, Megan E. McNerney, Steven J. Chmura, Ainhoa Arina, Sean P. Pitroda, Chuan He, Hua Liang, Ralph R. Weichselbaum

TSC/mTORC1 mediates mTORC2/AKT1 signaling in c-MYC-induced murine hepatocarcinogenesis via centromere protein M

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Abstract

Activated mTORC2/AKT signaling plays a role in hepatocellular carcinoma (HCC). Research has shown that TSC/mTORC1 and FOXO1 are distinct downstream effectors of AKT signaling in liver regeneration and metabolism. However, the mechanisms by which these pathways mediate mTORC2/AKT activation in HCC are not yet fully understood. Amplification and activation of c-MYC is a key molecular event in HCC. In this study, we explored the roles of TSC/mTORC1 and FOXO1 as downstream effectors of mTORC2/AKT1 in c-MYC-induced hepatocarcinogenesis. Using various genetic approaches in mice, we found that manipulating the FOXO pathway had minimal impact on c-MYC-induced HCC. In contrast, loss of mTORC2 inhibited c-MYC-induced HCC, an effect that was completely reversed by ablating TSC2, which activated mTORC1. Additionally, we discovered that p70/RPS6 and 4EBP1/eIF4E act downstream of mTORC1, regulating distinct molecular pathways. Notably, the 4EBP1/eIF4E cascade is crucial for cell proliferation and glycolysis in c-MYC-induced HCC. We also identified centromere protein M (CENPM) as a downstream target of the TSC2/mTORC1 pathway in c-MYC-driven hepatocarcinogenesis, and its ablation entirely inhibited c-MYC-dependent HCC formation. Our findings demonstrate that the TSC/mTORC1/CENPM pathway, rather than the FOXO cascade, is the primary signaling pathway regulating c-MYC-driven hepatocarcinogenesis. Targeting CENPM holds therapeutic potential for treating c-MYC-driven HCC.

Authors

Yi Zhou, Shu Zhang, guoteng Qiu, Xue Wang, Andrew Yonemura, Hongwei Xu, Guofei Cui, Shanshan Deng, Joanne Chun, Nianyong Chen, Meng Xu, Xinhua Song, Jingwen Wang, Zijing Xu, Youping Deng, Matthias Evert, Diego F. Calvisi, Shumei Lin, Haichuan Wang, Xin Chen

Innate immune cell activation by adjuvant AS01 in human lymph node explants is age-independent

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Abstract

Vaccine adjuvants are thought to work by stimulating innate immunity in the draining lymph node (LN), although this has not been proven in humans. To bridge data obtained in animals to humans, we have developed an in situ human LN explant model to investigate how adjuvants initiate immunity. Slices of explanted LNs were exposed to vaccine adjuvants and revealed responses that were not detectable in LN cell suspensions. We used this model to compare the liposome-based AS01 with its components MPL and QS-21, and TLR ligands. Liposomes were predominantly taken up by subcapsular sinus-lining macrophages, monocytes and dendritic cells. AS01 induced dendritic cell maturation and a strong pro-inflammatory cytokine response in intact LN slices but not in dissociated cell cultures, in contrast to R848. This suggests the onset of the immune response to AS01 requires a coordinated activation of LN cells in time and space. Consistent with the robust immune response observed in older adults with AS01-adjuvanted vaccines, the AS01 response in human LNs was independent of age, unlike R848. This human LN explant model is a valuable tool for studying the mechanism of action of adjuvants in humans and for screening new formulations to streamline vaccine development.

Authors

Vicki V. Stylianou, Kirstie M. Bertram, Van Anh Vo, Elizabeth B. Dunn, Heeva Baharlou, Darcii J. Terre, James Elhindi, Elisabeth Elder, James French, Farid Meybodi, Stéphane T. Temmerman, Arnaud M. Didierlaurent, Margherita Coccia, Kerrie J. Sandgren, Anthony L. Cunningham

Pharmacological regeneration of sensory hair cells restores afferent innervation and vestibular function

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Abstract

The sensory cells that transduce the signals for hearing and balance are highly specialized mechanoreceptors called hair cells that reside in the sensory epithelia of the inner ear. Loss of hair cells from toxin exposure and age can cause balance disorders and is essentially irreversible due to the inability of mammalian vestibular organs to regenerate physiologically active hair cells. Here, we show substantial regeneration of hair cells in a mouse model of vestibular damage by treatment with a combination of glycogen synthase kinase 3β and histone deacetylase inhibitors. The drugs stimulated supporting cell proliferation and differentiation into hair cells. The new hair cells were reinnervated by vestibular afferent neurons, rescuing otolith function by restoring head translation-evoked otolith afferent responses and vestibuloocular reflexes. Drugs that regenerate hair cells thus represent a potential therapeutic approach to the treatment of balance disorders.

Authors

Hanae Lahlou, Hong Zhu, Wu Zhou, Albert S.B. Edge

Proteogenomic analysis integrated with electronic health records data reveals disease-associated variants in Black Americans

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Abstract

BACKGROUND. Most genome wide association studies (GWAS) of plasma proteomics have focused on White individuals of European ancestry, limiting biological insight from other ancestry enriched protein quantitative loci (pQTL). METHODS. We conducted a discovery GWAS of ~3,000 plasma proteins measured by the antibody based Olink platform in 1,054 Black adults from the Jackson Heart Study (JHS), and validated our findings in the Multi-Ethnic Study of Atherosclerosis (MESA). The genetic architecture of identified pQTLs were further explored through fine mapping and admixture association analysis. Finally, using our pQTL findings, we performed a phenome wide association study (PheWAS) across two large multi-ethnic electronic health record (EHR) systems in All of Us and BioMe. RESULTS. We identified 1002 pQTLs for 925 proteins. Fine mapping and admixture analyses suggested allelic heterogeneity of the plasma proteome across diverse populations. We identified associations for variants enriched in African ancestry, many in diseases that lack precise biomarkers, including cis-pQTLs for Cathepsin L (CTSL) and Siglec-9 that were linked with sarcoidosis and non-Hodgkin’s lymphoma, respectively. We found concordant associations across clinical diagnoses and laboratory measurements, elucidating disease pathways, including a cis-pQTL associated with circulating CD58, white blood cell count, and multiple sclerosis. CONCLUSIONS. Our findings emphasize the value of leveraging diverse populations to enhance biological insights from proteomics GWAS, and we have made this resource readily available as an interactive web portal.

Authors

Usman A. Tahir, Jacob L. Barber, Daniel E. Cruz, Meltem Ece Kars, Shuliang Deng, Bjoernar Tuftin, Madeline G. Gillman, Mark D. Benson, Jeremy M. Robbins, Zsu-Zsu Chen, Prashant Rao, Daniel H. Katz, Laurie Farrell, Tamar Sofer, Michael E. Hall, Lynette Ekunwe, Russell P. Tracy, Peter Durda, Kent D. Taylor, Yongmei Liu, W. Craig Johnson, Xiuqing Guo, Yii-Der Ida Chen, Ani W. Manichaikul, Deepti Jain, Thomas J. Wang, Alex P. Reiner, Pradeep Natarajan, Yuval Itan, Stephen S. Rich, Jerome I. Rotter, James G. Wilson, Laura M. Raffield, Robert E. Gerszten

Modeling primary microcephaly with human brain organoids reveals fundamental roles of CIT kinase activity

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Abstract

Brain size and cellular heterogeneity are tightly regulated by species-specific proliferation and differentiation of multipotent neural progenitor cells (NPCs). Errors in this process are among the mechanisms of primary hereditary microcephaly (MCPH), a group of disorders characterized by reduced brain size and intellectual disability. Biallelic CIT missense variants that disrupt kinase function (CITKI/KI) and frameshift loss-of-function variants (CITFS/FS) are the genetic basis for MCPH17; however, the function of CIT catalytic activity in brain development and NPC cytokinesis is unknown. Therefore, we created the CitKI/KI mouse model and found that it does not phenocopy human microcephaly, unlike biallelic CitFS/FS animals. Nevertheless, both Cit models exhibited binucleation, DNA damage, and apoptosis. To investigate human-specific mechanisms of CIT microcephaly, we generated CITKI/KI and CITFS/FS human forebrain organoids. We found that CITKI/KI and CITFS/FS organoids lose cytoarchitectural complexity, transitioning from pseudostratified to simple neuroepithelium. This change was associated with defects that disrupt polarity of NPC cytokinesis, in addition to elevating apoptosis. Together, our results indicate that both CIT catalytic and scaffolding functions in NPC cytokinesis are critical for human corticogenesis. Species differences in corticogenesis and the dynamic 3D features of NPC mitosis underscore the utility of human forebrain organoid models for understanding human microcephaly.

Authors

Gianmarco Pallavicini, Amanda Moccia, Giorgia Iegiani, Roberta Parolisi, Emily R. Peirent, Gaia Elena Berto, Martina Lorenzati, Rami Y. Tshuva, Alessia Ferraro, Fiorella Balzac, Emilia Turco, Shachi U. Salvi, Hedvig F. Myklebust, Sophia Wang, Julia Eisenberg, Maushmi Chitale, Navjit S. Girgla, Enrica Boda, Orly Reiner, Annalisa Buffo, Ferdinando Di Cunto, Stephanie L. Bielas

Stimulation of an entorhinal-hippocampal extinction circuit facilitates fear extinction in a post-traumatic stress disorder model

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Abstract

Effective psychotherapy of post-traumatic stress disorder (PTSD) remains challenging due to the fragile nature of fear extinction, for which ventral hippocampal CA1 (vCA1) region is considered as a central hub. However, neither the core pathway nor the cellular mechanisms involved in implementing extinction are known. Here, we unveil a direct pathway, where layer 2a fan cells in the lateral entorhinal cortex (LEC) target parvalbumin-expressing interneurons (PV-INs) in the vCA1 region to propel low gamma-band synchronization of the LEC-vCA1 activity during extinction learning. Bidirectional manipulations of either hippocampal PV-INs or LEC fan cells sufficed fear extinction. Gamma entrainment of vCA1 by deep brain stimulation (DBS) or noninvasive transcranial alternating current stimulation (tACS) of LEC persistently enhanced the PV-IN activity in vCA1, thereby promoting fear extinction. These results demonstrate that the LEC-vCA1 pathway forms a top-down motif to empower low gamma-band oscillations that facilitate fear extinction. Finally, application of low gamma DBS and tACS to a mouse model with persistent PTSD showed potent efficacy, suggesting that the dedicated LEC-vCA1 pathway can be stimulated for therapy to remove traumatic memory trace.

Authors

Ze-Jie Lin, Xue Gu, Wan-Kun Gong, Mo Wang, Yan-Jiao Wu, Qi Wang, Xin-Rong Wu, Xin-Yu Zhao, Michael X. Zhu, Lu-Yang Wang, Quanying Liu, Ti-Fei Yuan, Wei-Guang Li, Tian-Le Xu

Egfl6 promotes ovarian cancer progression by enhancing the immunosuppressive functions of tumor-associated myeloid cells

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Abstract

Tumor-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs) play a critical role in resistance to immunotherapy. In this study, we identified epidermal growth factor-like 6 (Egfl6) as a new regulator of myeloid cell functions. Our analyses indicated that Egfl6, via binding with β3 integrins and activation of p38 and SYK signaling, acts as a chemotactic factor for myeloid cells migration and promotes their differentiation towards an immunosuppressive state. In syngeneic mouse models of ovarian cancer (OvCa), tumor expression of Egfl6 increased the intra-tumoral accumulation of polymorphonuclear (PMN) MDSCs and TAMs and their expression of immunosuppressive factors, including CXCL2, IL-10 and PD-L1. Consistent with this, in an immune ‘hot’ tumor model, Egfl6 expression eliminated response to a-PD-L1 therapy, while Egfl6 neutralizing antibody decreased the accumulation of tumor-infiltrating CD206+ TAMs and PMN-MDSCs and restored the efficacy of a-PD-L1 therapy. Supporting a role in human tumors, in human OvCa tissue samples, areas of high EGFL6 expression co-localized with myeloid cell infiltration. scRNAseq analyses revealed a correlation between EGFL6 and immune cell expression of immunosuppressive factors. Our data provide mechanistic insights into the onco-immunologic functions of EGFL6 in mediating tumor immune suppression and identified EGFL6 as a potential novel therapeutic target to enhance immunotherapy in OvCa patients.

Authors

Sarah Hamze Sinno, Joshua A. Imperatore, Shoumei Bai, Noémie Gomes-Jourdan, Nyasha Mafarachisi, Claudia Coronnello, Linan Zhang, Eldin Jašarević, Hatice U. Osmanbeyoglu, Ronald J. Buckanovich, Sandra Cascio

Long-lived lung megakaryocytes contribute to platelet recovery in thrombocytopenia models

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Abstract

Lung megakaryocytes (Mks) are largely extravascular with an immune phenotype (1). Because bone marrow (BM) Mks are short-lived it has been assumed that extravascular lung Mks are constantly ‘seeded’ from the BM. To investigate lung Mk origins and how that impacts their functions, we developed methods to specifically label lung Mks using CFSE dye and biotin delivered oropharyngeal. Labeled lung Mks were present for up to four months, while BM Mks had a <1 week lifespan. In a parabiosis model, lung Mks were partially replaced over 1-month from a circulating source. Unlike tissue-resident macrophages, using MDS1-Cre-ERT2 TdTomato mice, we found that lung Mks arise from hematopoietic stem cells. However, studies with FlkSwitch mTmG mice showed that lung Mks are derived from a Flt3-independent lineage that does not go through a multipotent progenitor. CFSE labeling to track lung Mk-derived platelets showed that about 10% of circulating platelets are lung resident Mk-derived at steady state, but in sterile thrombocytopenia this was doubled (about 20%). Lung-derived platelets were similarly increased in a malaria infection model (Plasmodium yoelii) typified by thrombocytopenia. These studies indicate that lung Mks arise from a Flt3-negative BM source, are long-lived, and contribute more platelets during thrombocytopenia.

Authors

Alison C. Livada, Kathleen E. McGrath, Michael W. Malloy, Chen Li, Sara K. Ture, Paul D. Kingsley, Anne D. Koniski, Leah A. Vit, Katherine E. Nolan, Deanne Mickelsen, Grace E. Monette, Preeti Maurya, James Palis, Craig N. Morrell

CRISPR–Cas13d targeting suppresses repeat-associated non-AUG translation of C9orf72 hexanucleotide repeat RNA

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Abstract

A hexanucleotide GGGGCC repeat expansion in the non-coding region of C9orf72 gene is the most common genetic mutation identified in patients with amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The resulting repeat RNA and dipeptide repeat proteins from non-conventional repeat translation have been recognized as important markers associated with the diseases. CRISPR-Cas13d, a powerful RNA targeting tool, has faced challenges in effectively targeting RNA with stable secondary structures. Here we report that CRISPR-Cas13d can be optimized to specifically target GGGGCC repeat RNA. Our results demonstrate that the CRISPR-Cas13d system can be harnessed to significantly diminish the translation of poly-dipeptides originating from the GGGGCC repeat RNA. This efficacy has been validated in various cell types, including induced pluripotent stem cells and differentiated motor neurons originating from C9orf72-ALS patients, as well as in C9orf72 repeat transgenic mice. These findings demonstrate the application of CRISPR-Cas13d in targeting RNA with intricate higher-order structures and suggest a potential therapeutic approach for ALS and FTD.

Authors

Honghe Liu, Xiao-Feng Zhao, Yu-Ning Lu, Lindsey R. Hayes, Jiou Wang

Natural TCRs targeting KRAS^G12V display fine specificity and sensitivity to human solid tumors

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Abstract

BACKGROUND. Neoantigens derived from KRASMUT have been described, but the fine antigen specificity of T cell responses directed against these epitopes are poorly understood. Here, we explore KRASMUT immunogenicity and the properties of 4 TCRs specific for KRASG12V restricted to HLA-A3 superfamily of class I alleles. METHODS. A phase I clinical vaccine trial targeting KRASMUT was conducted. TCRs targeting KRASG12V restricted to HLA-A*03:01 or HLA-A*11:01 were isolated from vaccinated patients or healthy individuals. A comprehensive analysis of TCR antigen specificity, affinity, cross-reactivity, and CD8 coreceptor dependence was performed. TCR lytic activity was evaluated, and target antigen density was determined by quantitative immunopeptidomics. RESULTS. Vaccination against KRASMUT resulted in the priming of CD8+ and CD4+ T cell responses. KRASG12V -specific natural (not affinity-enhanced) TCRs exhibited exquisite specificity to mutated protein with no discernable reactivity against KRASWT. TCR-recognition motifs were determined and used to identify and exclude cross-reactivity to non-cognate peptides derived from the human proteome. Both HLA-A*03:01 and HLA-A*11:01 restricted TCR-redirected CD8+ T cells exhibited potent lytic activity against KRASG12V cancers, while only HLA-A*11:01 restricted TCR-T CD4+ T cells exhibited anti-tumor effector functions consistent with partial co-receptor dependence. All KRASG12V-specific TCRs displayed high sensitivity for antigen as demonstrated by their ability to eliminate tumor cell lines expressing low levels of of peptide/HLA (4.4 to 242) complexes per cell. CONCLUSION. This study identifies KRASG12V-specific TCRs with high therapeutic potential for the development of TCR-T cell therapies. TRIAL REGISTRATION. ClinicalTrials.gov NCT03592888. FUNDING. AACR SU2C / Lustgarten Foundation, Parker Institute for Cancer Immunotherapy, and NIH (R01 CA204261, P01 CA217805, P30 CA016520).

Authors

Adham S. Bear, Rebecca B. Nadler, Mark H. O'Hara, Kelsey L. Stanton, Chong Xu, Robert J. Saporito, Andrew J. Rech, Miren L. Baroja, Tatiana Blanchard, Maxwell H. Elliott, Michael J. Ford, Richard C. Jones, Shivang Patel, Andrea L. Brennan, Zachary O'Neil, Daniel J. Powell Jr., Robert H. Vonderheide, Gerald P. Linette, Beatriz M. Carreno

Targeting aryl hydrocarbon receptor functionally restores tolerogenic dendritic cells derived from patients with multiple sclerosis

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Abstract

Multiple Sclerosis (MS) is a chronic disease characterized by dysregulated self-reactive immune responses that damage the neurons’ myelin sheath, leading to progressive disability. The primary therapeutic option, immunosuppressants, inhibits pathogenic anti-myelin responses but depresses the immune system. Antigen-specific monocyte-derived autologous tolerogenic dendritic cells (tolDCs) offer alternative therapeutic approaches to restore tolerance to auto-antigens without causing generalized immunosuppression. However, immune dysregulation in MS could impact the properties of the monocytes used as starting material for this cell therapy. Here, we characterized CD14+ monocytes, mature dendritic cells (mDCs) and Vitamin-D3-tolDCs (VitD3-tolDCs) from active, treatment-naive MS patients and healthy donors (HD). Using multi-omics, we identified a switch in these cell types towards proinflammatory features characterized by alterations in the AhR and NF-kB pathways. MS patient-derived VitD3-tolDCs showed reduced tolerogenic properties compared to those from HD, which were fully restored through direct AhR agonism and using in vivo or in vitro Dimethyl Fumarate (DMF) supplementation. Additionally, in the experimental autoimmune encephalomyelitis (EAE) mouse model, combined therapy of DMF and VitD3-tolDCs was more efficient than monotherapies in reducing the clinical score of mice. We propose that a combined therapy with DMF and VitD3-tolDCs offers enhanced therapeutic potential in treating MS.

Authors

Federico Fondelli, Jana Willemyns, Roger Domenech-Garcia, Maria José Mansilla, Gerard Godoy-Tena, Anna G. Ferreté-Bonastre, Alex Agúndez-Moreno, Silvia Presas-Rodriguez, Cristina Ramo-Tello, Esteban Ballestar, Eva Martínez-Cáceres

PAC1 constrains type II inflammation through promotion of CGRP signaling in ILC2s

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Abstract

Dysfunction of group II innate lymphoid cells (ILC2s) plays an important role in the development of type II inflammation-related diseases such as asthma and pulmonary fibrosis. Notably, neural signals are increasingly recognized as pivotal regulators of ILC2s. However, how ILC2s intrinsically modulate their responsiveness to these neural signals is still largely unknown. Here, using single-cell RNA sequencing, we found that the immune regulatory molecule PAC1 (phosphatase of activated cells 1) selectively promotes the signaling of neuropeptide CGRP (calcitonin gene-related peptide) in ILC2s through a cell-intrinsic manner. Genetic ablation of PAC1 in ILC2s substantially impaired the inhibitory effect of CGRP on proliferation and IL-13 secretion. PAC1 deficiency significantly exacerbated allergic airway inflammation induced by Alternaria alternata or papain in mice. Moreover, in human circulating ILC2s, the expression level of PAC1 was also significantly negatively correlated with the cell amount and the expression level of IL13. Mechanistically, PAC1 was necessary for ensuring the expression of CGRP-response genes by influencing chromatin accessibility. In summary, our study demonstrated that PAC1 is an important regulator of ILC2 responses and we proposed that PAC1 is a potential target for therapeutic interventions of type II inflammation-related diseases.

Authors

Yuan Jin, Bowen Liu, Qiuyu Li, Xiangyan Meng, Xiaowei Tang, Yan Jin, Yuxin Yin

Lactate supports Treg function and immune balance via MGAT1 effects on N-glycosylation in the mitochondria

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Abstract

Current research reports that lactate affects Treg metabolism, although the precise mechanism has only been partially elucidated. In this study, we presented evidence demonstrating that elevated lactate levels enhanced cell proliferation, suppressive capabilities, and oxidative phosphorylation (OXPHOS) in human Tregs. The expression levels of Monocarboxylate Transporters 1/2/4 (MCT1/2/4) regulate intracellular lactate concentration, thereby influencing the varying responses observed in naive Tregs and memory Tregs. Through mitochondrial isolation, sequencing, and analysis of human Tregs, we determined that Alpha-1,3-Mannosyl-Glycoprotein 2-Beta-N-Acetylglucosaminyltransferase (MGAT1) served as the pivotal driver initiating downstream N-glycosylation events involving progranulin (GRN) and hypoxia-upregulated 1 (HYOU1), consequently enhancing Treg OXPHOS. The mechanism by which MGAT1 was upregulated in mitochondria depended on elevated intracellular lactate that promoted the activation of XBP1s, which, in turn, supported MGAT1 transcription as well as the interaction of lactate with the translocase of the mitochondrial outer membrane 70 (TOM70) import receptor, facilitating MGAT1 translocation into mitochondria. Pre-treatment of Tregs with lactate reduced mortality in a xenogeneic graft-versus-host disease (GvHD) model. Together, these findings underscored the active regulatory role of lactate in human Treg metabolism through the upregulation of MGAT1 transcription and its facilitated translocation into the mitochondria.

Authors

Jinren Zhou, Jian Gu, Qufei Qian, Yigang Zhang, Tianning Huang, Xiangyu Li, Zhuoqun Liu, Qing Shao, Yuan Liang, Lei Qiao, Xiaozhang Xu, Qiuyang Chen, Zibo Xu, Yu Li, Ji Gao, Yufeng Pan, Yiming Wang, Roddy O'Connor, Keli L. Hippen, Ling Lu, Bruce R. Blazar

Postprandial metabolomics analysis reveals disordered serotonin metabolism in post-bariatric hypoglycemia

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Abstract

BACKGROUND. Bariatric surgery is a potent therapeutic approach for obesity and type 2 diabetes but can be complicated by post-bariatric hypoglycemia (PBH). PBH typically occurs 1 to 3 hours after meals, in association with exaggerated postprandial levels of incretins and insulin. METHODS. To identify mediators of disordered metabolism in PBH, we analyzed plasma metabolome in fasting state and 30 and 120 minutes after mixed meal in 3 groups: PBH (n = 13), asymptomatic post-RYGB (n = 10), and non-surgical controls (n = 8). RESULTS. In the fasting state, multiple tricarboxylic acid cycle intermediates and the ketone beta-hydroxybutyrate were increased by 30% to 80% in PBH vs. asymptomatic. Conversely, multiple amino acids (BCAA, tryptophan) and polyunsaturated lipids were reduced by 20% to 50% in PBH versus asymptomatic. Tryptophan-related metabolites, including kynurenate, xanthurenate, and serotonin, were reduced by 2- to 10-fold in PBH in fasting state. Postprandially, plasma serotonin was uniquely increased by 1.9-fold in PBH versus asymptomatic post-RYGB. In mice, serotonin administration lowered glucose and increased plasma insulin and GLP-1. Moreover, serotonin-induced hypoglycemia in mice was blocked by the nonspecific serotonin receptor antagonist cyproheptadine and the specific serotonin receptor 2 antagonist ketanserin. CONCLUSION. Together these data suggest that increased postprandial serotonin may contribute to the pathophysiology of PBH and provide a potential therapeutic target. FUNDING. NIH grant R01 DK121995, NIH grant P30 DK036836 (Diabetes Research Center grant, Joslin Diabetes Center), and Fundação de Amparo à Pesquisa do Estado de São Paulo-FAPESP grant 2018/22111-2.

Authors

Rafael Ferraz-Bannitz, Berkcan Ozturk, Cameron J. Cummings, Vissarion Efthymiou, Pilar Casanova Querol, Lindsay Poulos, Hanna J. Wang, Valerie Navarrete, Hamayle Saeed, Christopher M. Mulla, Hui Pan, Jonathan M. Dreyfuss, Donald C. Simonson, Darleen A. Sandoval, Mary-Elizabeth Patti

Uterine cyclin A2 deficient mice as a model of female early pregnancy loss

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Abstract

Proper action of the female sex steroids, 17β-estradiol (E2) and progesterone (P4) on endometrium is essential for fertility. Beyond its role in regulating the cell cycle, cyclin A2 (CCNA2) also mediates E2 and P4 signaling in vitro, but a potential role in modulating steroid action for proper endometrial tissue development and function is unknown. To fill this gap in our knowledge, we examined human endometrial tissue from fertile and infertile women for CCNA2 expression and correlated this with pregnancy outcome. Functional assessment of CCNA2 was validated in vivo using a conditional Ccna2 uterine deficient mouse model while in vitro function was assessed using human cell culture models. We found that CCNA2 expression was significantly reduced in endometrial tissue, specifically the stromal cells, from women undergoing in vitro fertilization who failed to achieve pregnancy. Conditional deletion of Ccna2 from mouse uterine tissue resulted in an inability to achieve pregnancy which appears to be due to alterations in the process of decidualization, which was confirmed using in vitro models. From these studies, we conclude that CCNA2 expression during the proliferative/regenerative stage of the menstrual cycle acts as a safeguard allowing for proper steroid responsiveness, decidualization and pregnancy. When CCNA2 expression levels are insufficient there is impaired endometrial responsiveness, aberrant decidualization and loss of pregnancy.

Authors

Fatimah Aljubran, Katelyn Schumacher, Amanda Graham, Sumedha Gunewardena, Courtney Marsh, Michael Lydic, Kristin Holoch, Warren B. Nothnick

A six-year study in a real-world population reveals an increased incidence of dyslipidemia during COVID-19

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Abstract

BACKGROUND. Recent studies conducted in COVID-19 survivors suggest that SARS-CoV-2 infection is associated with an increased risk of dyslipidemia. However, it remains unclear whether this augmented risk is confirmed in the general population and how this phenomenon is impacting the overall burden of cardiometabolic diseases. METHODS. To address these aspects, we conducted a 6-year longitudinal study to examine the broader effects of COVID-19 on dyslipidemia incidence within a real-world population (228,266 subjects) residing in Naples, Southern Italy. The pre-COVID-19 and the COVID-19 groups were balanced for demographic and clinical factors using propensity score matching. RESULTS. Our analysis spans over a period of three years during the pandemic (2020–2022), comparing dyslipidemia incidence with pre-pandemic data (2017–2019), with a follow-up time of at least 1,095 days corresponding to 21,349,215 person-years. During the COVID-19 period we detected an increased risk of developing any dyslipidemia when compared with the pre-COVID-19 triennium (OR = 1.29, 95% CI 1.19–1.39). Importantly, these estimates were adjusted for comorbidities by a multivariate analysis. CONCLUSIONS. Taken together, our data reveal a notable rise in dyslipidemia incidence amid the COVID-19 pandemic, suggesting to establish specialized clinical monitoring protocols for COVID-19 survivors to mitigate the risk of dyslipidemia development.

Authors

Valentina Trimarco, Raffaele Izzo, Stanislovas S. Jankauskas, Mario Fordellone, Giuseppe Signoriello, Maria Virginia Manzi, Maria Lembo, Paola Gallo, Giovanni Esposito, Roberto Piccinocchi, Francesco Rozza, Carmine Morisco, Pasquale Mone, Gaetano Piccinocchi, Fahimeh Varzideh, Bruno Trimarco, Gaetano Santulli

Epigenetic regulation of cell state by H2AFY governs immunogenicity in high-risk neuroblastoma

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Abstract

Childhood neuroblastoma with MYCN-amplification is classified as high-risk and often relapses after intensive treatments. Immune checkpoint blockade therapy against the PD-1/L1 axis shows limited efficacy in neuroblastoma patients and the cancer intrinsic immune regulatory network is poorly understood. Here, we leverage genome-wide CRISPR/Cas9 screens and identify H2AFY as a resistance gene to the clinically approved PD-1 blocking antibody, nivolumab. Analysis of single-cell RNA sequencing datasets reveals that H2AFY mRNA is enriched in adrenergic cancer cells and is associated with worse patient survival. Genetic deletion of H2afy in MYCN-driven neuroblastoma cells reverts in vivo resistance to PD-1 blockade by eliciting activation of the adaptive and innate immunity. Mapping of the epigenetic and translational landscape demonstrates that H2afy deletion promotes cell transition to a mesenchymal-like state. With a multi-omics approach, we uncover H2AFY-associated genes that are functionally relevant and prognostic in patients. Altogether, our study elucidates the role of H2AFY as an epigenetic gatekeeper for cell states and immunogenicity in high-risk neuroblastoma.

Authors

Divya Nagarajan, Rebeca T. Parracho, David Corujo, Minglu Xie, Ginte Kutkaite, Thale K. Olsen, Marta Rúbies Bedós, Maede Salehi, Ninib Baryawno, Michael P. Menden, Xingqi Chen, Marcus Buschbeck, Yumeng Mao