Mef2d sustains activation of effector Foxp3+ Tregs during transplant survival and anticancer immunity

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Abstract

The transcription factor, Mef2d, is important in the regulation of differentiation and adaptive responses in many cell types. Among T cells, Mef2d gains new functions in Foxp3+ T-regulatory (Treg) cells as a result of its interactions with the transcription factor, Foxp3, and its release from canonical partners, like histone/protein deacetylases. Though not necessary for the generation and maintenance of Tregs, Mef2d is required for the expression of IL-10, Ctla-4 and Icos, and for the acquisition of an effector Treg phenotype. At these loci, Mef2d acts both synergistically and additively to Foxp3, and down-stream of Blimp1. Mice with the conditional deletion in Tregs of the gene encoding Mef2d are unable to maintain long-term allograft survival despite costimulation blockade and have enhanced antitumor immunity in syngeneic models, but they display only minor evidence of autoimmunity when maintained under normal conditions. The role played by Mef2d in sustaining effector Foxp3+ Treg functions without abrogating their basal actions suggests its suitability for drug discovery efforts in cancer therapy.

Authors

Eros Di Giorgio, Liqing Wang, Yan Xiong, Tatiana Akimova, Lanette M. Christensen, Rongxiang Han, Arabinda Samanta, Matteo Trevisanut, Tricia R. Bhatti, Ulf H. Beier, Wayne W. Hancock

Truncated stathmin-2 is a marker of TDP-43 pathology in frontotemporal dementia

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Abstract

No treatment for frontotemporal dementia (FTD), the second most common early-onset dementia, is available but therapeutics are being investigated to target the two main proteins associated with FTD pathological subtypes: TDP-43 (FTLD-TDP) and tau (FTLD-tau). Testing potential therapies in clinical trials is hamstrung by our inability to distinguish between patients with FTLD-TDP and FTLD-tau. Therefore, we evaluated truncated stathmin-2 (STMN2) as a proxy of TDP-43 pathology, given reports that TDP-43 dysfunction causes truncated STMN2 accumulation. Truncated STMN2 accumulated in human iPSC-derived neurons depleted of TDP-43, but not in those with pathogenic TARDBP mutations in the absence of TDP-43 aggregation or loss of nuclear protein. In RNA-seq analyses of human brain samples from the NYGC ALS cohort, truncated STMN2 RNA was confined to tissues and disease sub-types marked by TDP-43 inclusions. Lastly, we validated that truncated STMN2 RNA is elevated in the frontal cortex of a cohort of FTLD-TDP cases but not in controls or cases with progressive supranuclear palsy (PSP), a type of FTLD-tau. Further, in FTLD-TDP, we observed significant associations of truncated STMN2 RNA with phosphorylated TDP-43 levels and an earlier age of disease onset. Overall, our data uncovered truncated STMN2 as a marker for TDP-43 dysfunction in FTD.

Authors

Mercedes Prudencio, Jack Humphrey, Sarah Pickles, Anna-Leigh Brown, Sarah E. Hill, Jennifer Kachergus, Ji Shi, Michael Heckman, Matthew Spiegel, Casey Cook, Yuping Song, Mei Yue, Lillian Daughrity, Yari Carlomagno, Karen Jansen-West, Cristhoper Fernandez De Castro, Michael DeTure, Shunsuke Koga, Ying-Chih Wang, Prasanth Sivakumar, Cristian Bodo, Ana Candalija, Kevin Talbot, Bhuvaneish T. Selvaraj, Karen Burr, Siddharthan Chandran, Jia Newcombe, Tammaryn Lashley, Isabel Hubbard, Demetra Catalano, Duyang Kim, Nadia Propp, Samantha Fennessey, Delphine Fagegaltier, Hemali Phatnani, Maria Secrier, Elizabeth M.C. Fisher, Björn Oskarsson, Marka van Blitterswijk, Rosa Rademakers, Neill R. Graff-Radford, Bradley Boeve, David S. Knopman, Ronald Petersen, Keith Josephs, E. Aubrey Thompson, Towfique Raj, Michael E. Ward, Dennis Dickson, Tania F. Gendron, Pietro Fratta, Leonard Petrucelli

Mutations affecting the conserved acidic WNK1 motif cause inherited hyperkalemic hyperchloremic acidosis

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Abstract

Gain-of-function mutations in the WNK1 and WNK4 genes are responsible for Familial Hyperkalemic Hypertension (FHHt), a rare inherited disorder characterized by arterial hypertension and hyperkalemia with metabolic acidosis. More recently, FHHt-causing mutations in the KLHL3-CUL3 E3 ubiquitin ligase complex have shed light on the importance of WNKs cellular degradation on renal ion transport. Using full exome sequencing in a four-generation family and then targeted sequencing in other suspected cases, we have identified new missense variants at the WNK1 gene, clustering in the short conserved acidic motif known to interact with the KLHL3-CUL3 ubiquitin complex. Affected subjects had an early-onset and a marked hyperkalemic phenotype, but normal blood pressure values. Functional experiments in Xenopus laevis oocytes and HEK293T cells demonstrated that these mutations strongly decrease the ubiquitination of the kidney-specific isoform KS-WNK1 by the KLHL3-CUL3 complex, rather than the long ubiquitous catalytically active L-WNK1 isoform. A corresponding CRISPR-Cas9 engineered mouse model recapitulated both the clinical and biological phenotype. Renal investigations showed increased activation of the SPAK-NCC phosphorylation cascade, associated with impaired ROMK apical expression in the distal part of the renal tubule. Altogether, these new WNK1 genetic variants highlight the importance of the KS-WNK1 isoform abundance on potassium homeostasis.

Authors

Helene Louis-Dit-Picard, Ilektra Kouranti, Chloe Rafael, Irmine Loisel-Ferreira, Maria Chavez-Canales, Waed Abdel Khalek, Eduardo Argaiz, Stephanie Baron, Sarah Vacle, Tiffany Migeon, Richard Coleman, Marcio Do Cruzeiro, Marguerite Hureaux, Nirubiah Thurairajasingam, Stéphane Decramer, Xavier Girerd, Kevin M. O'Shaughnessy, Paolo Mulatero, Gwenaelle Roussey, Ivan Tack, Robert J. Unwin, Rosa Vargas-Poussou, Olivier Staub, P. Richard Grimm, Paul A. Welling, Gerardo Gamba, Eric Clauser, Juliette Hadchouel, Xavier Jeunemaitre

COVID-19 severity associates with pulmonary redistribution of CD1c⁺ DC and inflammatory transitional and nonclassical monocytes

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Abstract

SARS-CoV-2 is responsible for development of COVID-19 in infected individuals, who can either exhibit mild symptoms or progress towards a life-threatening acute respiratory distress syndrome (ARDS). Exacerbated inflammation and dysregulated immune responses involving T and myeloid cells occur in COVID-19 patients with severe clinical progression. However, the differential contribution of specific subsets of dendritic cells and monocytes to ARDS is still poorly understood. In addition, the role of CD8+ T cells present in the lung of COVID-19 patients and relevant for viral control has not been characterized. Here, we have studied the frequencies and activation profiles of dendritic cells and monocytes present in the blood and lung of COVID-19 patients with different clinical severity in comparison with healthy individuals. Furthermore, these subpopulations and their association with antiviral effector CD8+ T cell subsets were also characterized in lung infiltrates from critical COVID-19 patients. Our results indicate that inflammatory transitional and non-classical monocytes and CD1c+ conventional dendritic cells preferentially migrate from blood to lungs in patients with severe COVID-19. Thus, this study increases the knowledge on specific myeloid subsets involved in the pathogenesis of COVID-19 disease and could be useful for the design of therapeutic strategies to fight SARS-CoV-2 infection.

Authors

Ildefonso Sánchez-Cerrillo, Pedro Landete, Beatriz Aldave, Santiago Sánchez-Alonso, Ana Sánchez-Azofra, Ana Marcos-Jiménez, Elena Ávalos, Ana Alcaraz-Serna, Ignacio de los Santos, Tamara Mateu-Albero, Laura Esparcia, Celia López-Sanz, Pedro Martínez-Fleta, Ligia Gabrie, Luciana del Campo Guerola, Hortensia de la Fuente, María J Calzada, Isidoro González-Álvaro, Arantzazu Alfranca, Francisco Sánchez-Madrid, Cecilia Muñoz-Calleja, Joan B. Soriano, Julio Ancochea, Enrique Martín-Gayo

Autologous CMV‐specific T cells are a safe adjuvant immunotherapy for primary glioblastoma multiforme

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Abstract

Background: The recent failure of checkpoint-blockade therapies for glioblastoma multiforme (GBM) in late-phase clinical trials has directed interest towards adoptive cellular immunotherapies (ACT). In this open-label, first-in-human trial, we have assessed the safety and therapeutic potential of cytomegalovirus (CMV)-specific ACT in an adjuvant setting for patients with primary GBM, with an ultimate goal to prevent or delay recurrence and prolong overall survival. Methods: Twenty-eight patients with primary GBM were recruited to this prospective study, 25 of whom were treated with in vitro-expanded autologous CMV-specific T cells. Participants were monitored for safety, progression-free survival (PFS), overall survival (OS) and immune reconstitution. Results: No participants showed evidence of ACT-related toxicities. Of 25 evaluable participants, ten were alive at the completion of follow-up, while five were disease free. Reconstitution of CMV-specific T-cell immunity was evident and CMV-specific ACT may trigger bystander effect leading to additional T-cell responses to non-viral tumour-associated antigens through epitope spreading. Long-term follow-up of participants treated before recurrence showed significantly improved OS when compared to those who progressed before ACT (median 23 months, range 7–65 vs. median 14 months, range 5–19; p=0.018). Gene expression analysis of the ACT products indicated that a favourable T-cell gene signature was associated with improved long-term survival. Conclusion: Data presented in this study demonstrate that CMV-specific ACT can be safely used as an adjuvant therapy for primary GBM and, if offered before recurrence, this therapy may improve overall survival of GBM patients.Trial registration: anzctr.org.au: ACTRN12615000656538Funding Source:National Health & Medical Research Council (Australia) Trial registration: anzctr.org.au: ACTRN12615000656538 Funding Source: Philanthropic funding &National Health & Medical Research Council (Australia)

Authors

Corey Smith, Katie E. Lineburg, J. Paulo Martins, George Ambalathingal, Michelle A. Neller, Beth Morrison, Katherine K. Matthews, Sweera Rehan, Pauline Crooks, Archana Panikkar, Leone Beagley, Laetitia Le Texier, Sriganesh Srihari, David Walker, Rajiv Khanna

Metabolic effects of air pollution exposure and reversibility

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Abstract

Particulate matter < 2.5 micrometers (PM2.5) air pollution is the world’s leading environmental risk factor contributing to mortality through cardiometabolic pathways. In this study, we modeled early life exposure using chow-fed C57BL/6J male mice, exposed to real-world inhaled concentrated PM2.5 (~10 times ambient levels / ~60-120ug/m3) or filtered air over 14 weeks. We investigated PM2.5 effects on phenotype, transcriptome and chromatin accessibility, compared the effects with a prototypical high-fat diet (HFD) stimulus, and examined cessation of exposure on reversibility of phenotype. Exposure to PM2.5 impaired glucose and insulin tolerance, reduced energy expenditure and 18FDG-PET uptake in brown adipose tissue. Multiple differentially expressed gene (DEG) clusters in pathways involving metabolism and circadian rhythm were noted in insulin responsive tissues. Although the magnitude of transcriptional change seen with PM2.5 was lower than HFD, the degree of alteration in chromatin accessibility after PM2.5 exposure was significant. A novel chromatin remodeler SMARCA5 (SWI/SNF complex) was regulated in response to PM2.5 with cessation of exposure associated with reversal of insulin resistance, restoration of chromatin accessibility/nucleosome positioning near transcription start sites (TSS) and exposure induced changes in the transcriptome including SMARCA5, indicating pliable epigenetic control mechanisms following exposure cessation.

Authors

Sanjay Rajagopalan, Bongsoo Park, Rengasamy Palanivel, Vinesh Vinayachandran, Jeffrey A. Deiuliis, Roopesh Singh Gangwar, Lopa M. Das, Jinhu Yin, Youngshim Choi, Sadeer Al-Kindi, Mukesh K. Jain, Kasper D. Hansen, Shyam Biswal

Sleeping Beauty-engineered CAR T cells achieve anti-leukemic activity without severe toxicities

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Abstract

Background. Chimeric antigen receptor (CAR) T cell immunotherapy has achieved complete remission and durable response in highly refractory patients. However, logistical complexity and high costs of manufacturing autologous viral products limit CAR T cell availability. Methods. We reported the early results of a phase I/II trial in B-cell acute lymphoblastic leukemia (B-ALL) patients relapsed after allogeneic hematopoietic stem cell transplantation (HSCT) using donor-derived CD19 CAR T cells generated with the Sleeping Beauty (SB) transposon and differentiated into cytokine induced killer cells (CIK). Results. The cellular product was produced successfully for all patients from the donor peripheral blood (PB) and consisted mostly of CD3+ lymphocytes with 43% CAR expression. Four pediatric and 9 adult patients were infused with a single dose of CAR T cells. Toxicities reported were two grade I and a grade II cytokine release syndrome (CRS) cases at the highest dose, in the absence of graft-versus-host disease (GvHD), neurotoxicity, or dose-limiting toxicities. Six out of 7 patients, receiving the highest doses, achieved CR and CRi at day 28. Five out of 6 patients in CR were also minimal residual disease (MRD)-negative. Robust expansion was achieved in the majority of the patients. CAR T cells were measurable by transgene copy PCR up to 10 months. Integration site analysis showed a positive safety profile and highly polyclonal repertoire in vitro and at early time points after infusion. Conclusion. SB-engineered CAR T cells expand and persist in pediatric and adult B-ALL patients relapsed after HSCT. Anti-leukemic activity was achieved without severe toxicities. Trial registration. clinicaltrials.gov NCT03389035.Funding. This study was supported by grants from AIRC; CRUK; FC AECC; Ministero della salute; FRRB.

Authors

Chiara F. Magnani, Giuseppe Gaipa, Federico Lussana, Daniela Belotti, Giuseppe Gritti, Sara Napolitano, Giada Matera, Benedetta Cabiati, Chiara Buracchi, Gianmaria Borleri, Grazia Fazio, Silvia Zaninelli, Sarah Tettamanti, Stefania Cesana, Valentina Colombo, Michele Quaroni, Giovanni Cazzaniga, Attilio Rovelli, Ettore Biagi, Stefania Galimberti, Andrea Calabria, Fabrizio Benedicenti, Eugenio Montini, Silvia Ferrari, Martino Introna, Adriana Balduzzi, Maria Grazia Valsecchi, Giuseppe Dastoli, Alessandro Rambaldi, Andrea Biondi

Type 2 diabetes risk gene Dusp8 regulates hypothalamic Jnk signaling and insulin sensitivity

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Abstract

Recent genome-wide association studies (GWAS) identified DUSP8, a dual-specificity phosphatase targeting MAP kinases, as type 2 diabetes (T2D) risk gene. Here, we unravel Dusp8 as gatekeeper in the hypothalamic control of glucose homeostasis in mice and humans. Male but not female Dusp8 loss-of-function mice, either with global or CRH neuron-specific deletion, had impaired systemic glucose tolerance and insulin sensitivity when exposed to high-fat diet (HFD). Mechanistically, we found impaired hypothalamic–pituitary–adrenal (HPA) axis feedback, blunted sympathetic responsiveness, and chronically elevated corticosterone levels driven by hypothalamic hyperactivation of Jnk signaling. Accordingly, global Jnk1 ablation, AAV-mediated Dusp8 overexpression in the mediobasal hypothalamus, or metyrapone-induced chemical adrenalectomy rescued the impaired glucose homeostasis of obese male Dusp8 KO mice, respectively. The sex-specific role of murine Dusp8 in governing hypothalamic Jnk signaling, insulin sensitivity and systemic glucose tolerance was consistent with fMRI data in human volunteers that revealed an association of the DUSP8 rs2334499 risk variant with hypothalamic insulin resistance in men. Further, expression of DUSP8 was increased in the infundibular nucleus of T2D humans. In summary, our findings suggest the GWAS-identified gene Dusp8 as novel hypothalamic factor that plays a functional role in the etiology of T2D.

Authors

Sonja C. Schriever, Dhiraj G. Kabra, Katrin Pfuhlmann, Peter Baumann, Emily V. Baumgart, Joachim Nagler, Fabian Seebacher, Luke Harrison, Martin Irmler, Stephanie Kullmann, Felipe Corrêa-da-Silva, Florian Giesert, Ruchi Jain, Hannah Schug, Julien Castel, Sarah Martinez, Moya Wu, Hans-Ulrich Häring, Martin Hrabe de Angelis, Johannes Beckers, Timo D. Müller, Kerstin Stemmer, Wolfgang Wurst, Jan Rozman, Rubén Nogueiras, Meri De Angelis, Jeffery D. Molkentin, Natalie Krahmer, Chun-Xia Yi, Mathias V. Schmidt, Serge Luquet, Martin Heni, Matthias H. Tschoep, Paul T. Pfluger

Sex, age, and hospitalization drive antibody responses in a COVID-19 convalescent plasma donor population

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Abstract

Convalescent plasma is a leading treatment for COVID-19, but there is a paucity of data identifying therapeutic efficacy. Among 126 potential convalescent plasma donors, the humoral immune response was evaluated by a SARS-CoV-2 virus neutralization assay using Vero-E6-TMPRSS2 cells, commercial IgG and IgA ELISA to spike(S) protein S1 domain (Euroimmun), IgA, IgG and IgM indirect ELISAs to the full-length S or S-receptor binding domain(S-RBD), and an IgG avidity assay. Multiple linear regression and predictive models were utilized to assess the correlations between antibody responses with demographic and clinical characteristics. IgG titers were greater than either IgM or IgA for S1, full length S, and S-RBD in the overall population. Of the 126 plasma samples, 101(80%) had detectable neutralizing antibody(nAb) titers. Using nAb titers as the reference, the IgG ELISAs confirmed between 95-98% of the nAb positive, but only 20-32% of the nAb negative samples. Male sex, older age, and hospitalization with COVID-19 were associated with increased antibody responses across the serological assays. There was substantial heterogeneity in the antibody response among potential convalescent plasma donors, but sex, age, and hospitalization emerged as factors that can be used to identify individuals with a high likelihood of having strong antiviral antibody responses.

Authors

Sabra L. Klein, Andrew Pekosz, Han-Sol Park, Rebecca L. Ursin, Janna R. Shapiro, Sarah E. Benner, Kirsten Littlefield, Swetha Kumar, Harnish Mukesh Naik, Michael Betenbaugh, Ruchee Shrestha, Annie A. Wu, Robert M. Hughes, Imani Burgess, Patrizio Caturegli, Oliver Laeyendecker, Thomas C. Quinn, David J. Sullivan, Shmuel Shoham, Andrew D. Redd, Evan M. Bloch, Arturo Casadevall, Aaron A. R. Tobian

Complement and tissue factor-enriched neutrophil extracellular traps are key drivers in COVID-19 immunothrombosis

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Abstract

Emerging data indicate that complement and neutrophils contribute to the maladaptive immune response that fuels hyper-inflammation and thrombotic microangiopathy, thereby increasing COVID-19 mortality. Here, we investigated how complement interacts with the platelet/neutrophil extracellular traps (NETs)/thrombin axis, using COVID-19 specimens, cell-based inhibition studies and NETs/human aortic endothelial cell (HAEC) co-cultures. Increased plasma levels of NETs, tissue factor (TF) activity and sC5b-9 were detected in patients. Neutrophils of patients yielded high TF expression and released NETs carrying active TF. Treatment of control neutrophils with COVID-19 platelet-rich plasma generated TF-bearing NETs that induced thrombotic activity of HAEC. Thrombin or NETosis inhibition or C5aR1 blockade attenuated platelet-mediated NET-driven thrombogenicity. COVID-19 serum induced complement activation in vitro, consistent with high complement activity in clinical samples. Complement C3 inhibition with compstatin Cp40 disrupted TF expression in neutrophils. In conclusion, we provide a mechanistic basis for a pivotal role of complement and NETs in COVID-19 immunothrombosis. This study supports strategies against SARS-CoV-2 that exploit complement or NETosis inhibition.

Authors

Panagiotis Skendros, Alexandros Mitsios, Akrivi Chrysanthopoulou, Dimitrios C. Mastellos, Simeon Metallidis, Petros Rafailidis, Maria Ntinopoulou, Eleni Sertaridou, Victoria Tsironidou, Christina Tsigalou, Maria G. Tektonidou, Theocharis Konstantinidis, Charalampos Papagoras, Ioannis Mitroulis, Georgios Germanidis, John D. Lambris, Konstantinos Ritis