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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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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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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

Inhibition of mitophagy drives macrophage activation and anti-bacterial defense during sepsis

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Mitochondria have emerged as key actors of innate and adaptive immunity. Mitophagy has a pivotal role in cell homeostasis but its contribution to macrophage functions and host defense remains to be delineated. Here we showed that lipopolysaccharide (LPS) in combination with IFNγ, inhibits PINK1-dependent mitophagy in macrophages through a STAT1-dependent activation of the inflammatory caspases 1 and 11. In addition, we demonstrated that the inhibition of mitophagy triggers classical macrophage activation in a mitochondrial ROS-dependent manner. In a murine model of polymicrobial infection (cecal ligature and puncture, CLP), adoptive transfer of Pink1-deficient bone marrow or pharmacological inhibition of mitophagy promoted macrophage activation which favored bactericidal clearance and lead to a better survival. Reciprocally, mitochondrial uncouplers, that promote mitophagy, reverse LPS/IFNγ-mediated activation of macrophages and lead to immuno-paralysis with impaired bacterial clearance and lowered survival. In critically ill patients, we showed that mitophagy is inhibited in blood monocytes of patients with sepsis as compared to non-septic patients. Overall, this work demonstrates that the inhibition of mitophagy is a physiological mechanism that contributes to the activation of myeloid cells and improves the outcome of sepsis.

Authors

Danish Patoli, Franck Mignotte, Valérie Deckert, Alois Dusuel, Adelie Dumont, Aurelie Rieu, Antoine Jalil, Kevin Van Dongen, Thibaut Bourgeois, Thomas Gautier, Charlene Magnani, Naig Le Guern, Stéphane Mandard, Jean Bastin, Fatima Djouadi, Christine Schaeffer, Nina Guillaumot, Michel Narce, Maxime Nguyen, Julien Guy, Auguste Dargent, Jean-Pierre Quenot, Mickaël Rialland, David Masson, Johan Auwerx, Laurent Lagrost, Charles Thomas

Hypoxia-inducible factors and innate immunity in liver cancer

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The liver has strong innate immunity to counteract pathogens from the gastrointestinal tract. During the development of liver cancer, which is typically driven by chronic inflammation, the composition and biological roles of the innate immune cells are extensively altered. Hypoxia is a common finding in all stages of liver cancer development. Hypoxia drives the stabilization of hypoxia-inducible factors (HIFs), which act as central regulators to dampen the innate immunity of liver cancer. HIF signaling in innate immune cells and liver cancer cells together favor the recruitment and maintenance of pro-tumorigenic immune cells and the inhibition of anti-tumorigenic immune cells, promoting immune evasion. HIFs represent attractive therapeutic targets to inhibit the formation of an immunosuppressive microenvironment and growth of liver cancer.

Authors

Vincent Wai-Hin Yuen, Carmen Chak-Lui Wong

Dominant-negative NFKBIA mutation promotes IL-1β production causing hepatic disease with severe immunodeficiency

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Although IKK-β has previously been shown as a negative regulator of IL-1β secretion in mice, this role has not been demonstrated in humans. Genetic studies of NF-κB signalling in humans with inherited diseases of the immune system have not demonstrated the relevance of the NF-κB pathway in suppression of IL-1β expression. Here, we report an infant displaying clinical pathology comprising neutrophil-mediated auto-inflammation and recurrent bacterial infections. Whole-exome sequencing revealed a de novo heterozygous missense mutation in NFKBIA, resulting in a L34P IκBα variant, that severely repressed NF-κB activation and downstream cytokine production. Paradoxically, IL-1β secretion was elevated in the patient’s stimulated leukocytes, in her induced-pluripotent stem cell-derived macrophages, and in murine bone marrow-derived macrophages containing the L34P mutation. The patient’s hyper-IL-1β secretion correlated with activated neutrophilia and liver fibrosis with neutrophil accumulation. Hematopoietic stem cell transplantation reversed neutrophilia, restored a resting state in neutrophils, and normalized IL-1β release from stimulated leukocytes. Additional therapeutic blockade of IL-1 ameliorated liver damage, whilst decreasing neutrophil activation and associated IL-1β secretion. Our studies reveal a previously unrecognized role of human IκBα as an essential regulator of canonical NF-κB signalling in the prevention of neutrophilic-dependent auto-inflammatory diseases. We showed that IκBα controls IL-1β secretion through a mechanism of self-limiting post-transcriptional regulation. These findings also highlight a therapeutic potential for IL-1 inhibitors to treat complications arising from systemic NF-κB inhibition.

Authors

Enrica Ee Kar Tan, Richard Hopkins, Chrissie K. Lim, Saumya Jamuar, Christina Ong, Koh Cheng Thoon, Mark J.A. Koh, Eun Myoung Shin, Derrick Wen Quan Lian, Madhushanee Weerasooriya, Christopher Z.W Lee, Andreas Alvin Purnomo Soetedjo, Chang Siang Lim, Veronica B. Au, WM Edmond Chua, Hui Yin Lee, Leigh Ann Jones, Sharmy Jennifer James, Nivashini Kaliaperumal, Jeffrey Kwok, Ee Shien Tan, Biju Thomas, Lena Ho, Lynn Wu, Anna-Marie Fairhurst, Florent Ginhoux, Adrian K.K. Teo, Yongliang Zhang, Kok Haur Ong, Weimiao Yu, Byrappa Venkatesh, Vinay Tergaonkar, Bruno Reversade, Keh-Chuang Chin, Ah Moy Tan, Woei Kang Liew, John E. Connolly

Protein phosphatase 2A B55ß limits CD8 T cell lifespan following cytokine withdrawal

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How T cells integrate environmental cues into signals that limit the magnitude and length of immune responses is poorly understood. Here, we provide data that demonstrates that B55ß, a regulatory subunit of the phosphatase PP2A, represents a molecular link between cytokine concentration and apoptosis in activated CD8 T cells. Through the modulation of AKT, B55ß induced the expression of the pro-apoptotic molecule Hrk in response to cytokine withdrawal. Accordingly, B55ß and Hrk were both required for in vivo and in vitro contraction of activated CD8 lymphocytes. We show that this process plays a role during clonal contraction, establishment of immune memory, and preservation of peripheral tolerance. This regulatory pathway may represent an unexplored opportunity to end unwanted immune responses, or to promote immune memory.

Authors

Noé Rodríguez-Rodríguez, Iris K. Madera-Salcedo, J. Alejandro Cisneros-Segura, H. Benjamin García-González, Sokratis A. Apostolidis, Abril Saint-Martin, Marcela Esquivel-Velázquez, Tran Nguyen, Dámaris P. Romero-Rodríguez, George C. Tsokos, Jorge Alcocer-Varela, Florencia Rosetti, Jose C. Crispin

BIN2 orchestrates platelet calcium signaling in thrombosis and thrombo-inflammation

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Store-operated calcium entry (SOCE) is the major route of Ca2+ influx in platelets. The Ca2+ sensor stromal interaction molecule 1 (STIM1) triggers SOCE by forming puncta structures with the Ca2+ channel Orai1 and the inositol trisphosphate receptor (IP3R), thereby linking the endo-/sarcoplasmic reticulum to the plasma membrane. Here, we identified the BAR domain superfamily member bridging integrator 2 (BIN2) as an interaction partner of STIM1 and IP3R in platelets. Deletion of platelet Bin2 (Bin2fl/fl,Pf4-Cre mice) resulted in reduced Ca2+ store release and Ca2+ influx in response to all tested platelet agonists. These defects were a consequence of impaired IP3R function in combination with defective STIM1-mediated SOC channel activation, while Ca2+ store content and agonist-induced IP3 production were unaltered. These defects translated into impaired thrombus formation under flow and a protection of Bin2fl/fl,Pf4-Cre mice in models of arterial thrombosis and stroke. These results establish BIN2 as a central regulator of platelet activation in thrombosis and thrombo-inflammatory disease settings.

Authors

Julia Volz, Charly Kusch, Sarah Beck, Michael Popp, Timo Vögtle, Mara Meub, Inga Scheller, Hannah S. Heil, Julia Preu, Michael K. Schuhmann, Katherina Hemmen, Thomas Premsler, Albert Sickmann, Katrin G. Heinze, David Stegner, Guido Stoll, Attila Braun, Markus Sauer, Bernhard Nieswandt

COVID-19, racism, and the pursuit of health care and research worthy of trust

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This Viewpoint describes how physicians and researchers can utilize approaches based on relationship-centered care and structural competence to reduce racism and enhance trustworthiness in health care and biomedical research.

Authors

Lisa A. Cooper, Deidra C. Crews

Complement activation on endothelium initiates antibody-mediated acute lung injury

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Antibodies targeting human leukocyte antigen (HLA)/major histocompatibility complex (MHC) proteins limit successful transplantation and transfusion, and their presence in blood products can cause lethal transfusion-related acute lung injury (TRALI). It is unclear which cell types are bound by these ‘anti-leukocyte’ antibodies to initiate an immunologic cascade resulting in lung injury. We therefore conditionally removed MHC class I (MHC I) from likely cellular targets in antibody-mediated lung injury. Only the removal of endothelial MHC I reduced lung injury and mortality, related mechanistically to absent endothelial complement fixation and lung platelet retention. Restoration of endothelial MHC I rendered MHC I-deficient mice susceptible to lung injury. Neutrophil responses, including neutrophil extracellular trap (NET) release, were intact in endothelial MHC I-deficient mice, whereas complement depletion reduced both lung injury and NETs. Human pulmonary endothelial cells showed high HLA class I expression, and post-transfusion complement activation was increased in clinical TRALI. These results indicate that the critical source of antigen for ‘anti-leukocyte’ antibodies is in fact the endothelium, which reframes our understanding of TRALI as a rapid-onset vasculitis. Inhibition of complement activation may have multiple beneficial effects of reducing endothelial injury, platelet retention, and NET release in conditions where antibodies trigger these pathogenic responses.

Authors

Simon J. Cleary, Nicholas Kwaan, Jennifer J. Tian, Daniel R. Calabrese, Beñat Mallavia, Mélia Magnen, John R. Greenland, Anatoly Urisman, Jonathan P. Singer, Steven R. Hays, Jasleen Kukreja, Ariel M. Hay, Heather L. Howie, Pearl Toy, Clifford A. Lowell, Craig N. Morrell, James C. Zimring, Mark R. Looney

Multisystem inflammatory syndrome in children and COVID-19 are distinct presentations of SARS-CoV-2

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Background: Initial reports from the Severe Acute Respiratory Coronavirus 2 (SARS-CoV-2) pandemic described children as being less susceptible to Coronavirus Disease 2019 (COVID-19) than adults. Subsequently, a severe and novel pediatric disorder termed Multisystem Inflammatory Syndrome in Children (MIS-C) emerged. We report on unique hematologic and immunologic parameters that distinguish between COVID-19 and MIS-C and provide insight into pathophysiology. Methods: We prospectively enrolled hospitalized patients with evidence of SARS-CoV-2 infection and classified them as having MIS-C or COVID-19. Patients with COVID-19 were classified as having either minimal or severe disease. Cytokine profiles, viral cycle thresholds (Cts), blood smears, and soluble C5b-9 values were analyzed with clinical data. Twenty patients were enrolled (9 severe COVID-19, 5 minimal COVID-19, and 6 MIS-C). Five cytokines (IFN-γ, IL-10, IL-6, IL-8 and TNF-α) contributed to the analysis. TNF-α and IL-10 discriminated between patients with MIS-C and severe COVID-19. Cts and burr cells on blood smears also differentiated between patients with severe COVID-19 and those with MIS-C. Conclusion: Pediatric patients with SARS-CoV-2 are at risk for critical illness with severe COVID-19 and MIS-C. Cytokine profiling and examination of peripheral blood smears may distinguish between patients with MIS-C and severe COVID-19.

Authors

Caroline Diorio, Sarah E. Henrickson, Laura A. Vella, Kevin O. McNerney, Julie M. Chase, Chakkapong Burudpakdee, Jessica H. Lee, Cristina Jasen, Fran Balamuth, David M. Barrett, Brenda Banwell, Kathrin M. Bernt, Allison M. Blatz, Kathleen Chiotos, Brian T. Fisher, Julie C. Fitzgerald, Jeffrey S. Gerber, Kandace Gollomp, Christopher Gray, Stephan A. Grupp, Rebecca M. Harris, Todd J. Kilbaugh, Audrey R. Odom John, Michele P. Lambert, Emily J. Liebling, Michele Paessler, Whitney Petrosa, Charles A. Phillips, Anne F. Reilly, Neil Romberg, Alix E. Seif, Deborah Sesok-Pizzini, Kathleen Sullivan, Julie Vardaro, Edward M Behrens, David T. Teachey, Hamid Bassiri

Hypoxia inducible factors (HIFs) and obstructive sleep apnea

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Intermittent hypoxia (IH) is a hallmark manifestation of obstructive sleep apnea (OSA), a widespread disorder of breathing. This review focuses on the role of hypoxia-inducible factors (HIFs) in hypertension, type 2 diabetes (T2D), and cognitive decline in experimental models of IH patterned after O2 profiles seen in OSA. IH increases HIF-1α and decreases HIF-2α protein levels. Dysregulated HIFs increase reactive oxygen species (ROS) through HIF-1-dependent activation of pro-oxidant enzyme genes in addition to reduced transcription of anti-oxidant genes by HIF-2. ROS in turn activates chemoreflex and suppresses baroreflex, thereby stimulating the sympathetic nervous system and causing hypertension. We will also discuss how increased ROS generation by HIF-1 also contributes to IH-induced insulin resistance and T2D as well as disrupted NMDA receptor signaling in the hippocampus, resulting in cognitive decline.

Authors

Nanduri R. Prabhakar, Ying-Jie Peng, Jayasri Nanduri

DCAF1 regulates Treg senescence via the ROS axis during immunological ageing

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As a hallmark of immunological ageing, the low-grade, chronic inflammation with accumulation of effector-memory T cells contributes to the increased susceptibility of many ageing-related diseases. While the proinflammatory state of aged T cells indicates a dysregulation of immune homeostasis, whether and how ageing drives regulatory T (Treg) cell ageing and alters their function is not fully understood due to a lack of specific ageing markers. Here, by a combination of cellular, molecular and bioinformatic approaches, we discover that Treg cells senesce more severely than conventional T (Tconv) cells during ageing. We found Treg cells from aged mice were less efficient than young Treg cells to suppress Tconv cell function in an inflammatory-bowel-disease model and to prevent Tconv cell ageing in the irradiation-induced ageing model. Furthermore, we revealed that DCAF1 (DDB1 and CUL4 associated factor 1) was downregulated in aged Treg cells and was critical to restrain Treg cell ageing via glutathione S-transferase P (GSTP1) regulated reactive-oxygen-species (ROS). Importantly, interfering with GSTP1 and ROS pathways reinvigorated the proliferation and function of aged Treg cells. Therefore, our studies uncover an important role of DCAF1-GSTP1-ROS axis in Treg cell senescence, which leads to uncontrolled inflammation and immunological ageing.

Authors

Zengli Guo, Gang Wang, Bing Wu, Wei-Chun Chou, Liang Cheng, Chenlin Zhou, Jitong Lou, Di Wu, Lishan Su, Junnian Zheng, Jenny Pan-Yun Ting, Yisong Y. Wan

Is multisystem inflammatory syndrome in children on the Kawasaki syndrome spectrum?

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An alarming increase in children presenting with fever, hyperinflammation and multiorgan dysfunction frequently requiring intensive care has been observed after SARS-CoV-2 infection. The illness resembles Kawasaki Disease (KD) with coronary dilatation and aneurysm occurring in some. However, the cardiovascular manifestations were typically on the severe end of the KD spectrum with cardiogenic shock a common presentation together with other features. This led to defining a unique syndrome named multisystem inflammatory syndrome in Children (MIS-C). In this issue of the JCI, Lee and Day-Lewis et al. and Diorio et al. explored the clinical profiles associated with COVID-19 in children. We posit that while splitting MIS-C into a separate disease may aid clinical management decisions, lumping it into the KD pot may better serve to understand pathobiology.

Authors

Rae S.M. Yeung, Polly J. Ferguson

Stiff stroma increases breast cancer risk by inducing the oncogene ZNF217

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Women with dense breasts have an increased lifetime risk to malignancy that has been attributed to a higher epithelial density. Quantitative proteomics, collagen analysis and mechanical measurements in normal tissue revealed that stroma in the high density breast contains more oriented, fibrillar collagen, that is stiffer and correlates with higher epithelial cell density. MicroRNA profiling of breast tissue identified microRNA-203 (miR-203) as a matrix stiffness-repressed transcript that is downregulated by collagen density and reduced in the breast epithelium of women with high mammographic density. Culture studies demonstrated that ZNF217 mediates a matrix stiffness and collagen density-induced increase in Akt activity and mammary epithelial cell proliferation. Manipulation of the epithelium in a mouse model of mammographic density supported a causal relationship between stromal stiffness, reduced miR-203, higher levels of the murine homologue Zfp217, and increased Akt activity and mammary epithelial proliferation. ZNF217 was also increased in the normal breast epithelium of women with high mammographic density, correlated positively with epithelial proliferation and density, and inversely with miR-203. The findings identify ZNF217 as a potential target towards which preexisting therapies, such as the Akt inhibitor triciribine, could be used as a chemoprevention agent to reduce cancer risk in women with high mammographic density.

Authors

Jason J. Northey, Alexander S. Barrett, Irene Acerbi, Mary-Kate Hayward, Stephanie Talamantes, Ivory S. Dean, Janna K. Mouw, Suzanne M. Ponik, Johnathon N. Lakins, Po-Jui Huang, Junmin Wu, Quanming Shi, Susan Samson, Patricia J. Keely, Rita A. Mukhtar, Jan T. Liphardt, John A. Shepherd, E. Shelley Hwang, Yunn-Yi Chen, Kirk C. Hansen, Laurie E. Littlepage, Valerie M. Weaver

Arginase expression impedes the resolution of intestinal inflammation by altering the fecal microbiome and the metabolome

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Arginase 1 (Arg1), which converts L-arginine into ornithine and urea, exerts pleiotropic immunoregulatory effects. However, the function of Arg1 in inflammatory bowel disease (IBD) remains poorly characterized. Here, we found that Arg1 expression correlated with the degree of inflammation in intestinal tissues from IBD patients. In mice, Arg1 was upregulated in an IL-4-/IL-13- and intestinal microbiota-dependent manner. Tie2-Cre+/-Arg1fl/fl mice lacking Arg1 in hematopoietic and endothelial cells recovered faster from experimental colitis than Arg1-expressing littermates. This correlated with decreased vessel density, compositional changes in intestinal microbiota, diminished infiltration by myeloid cells and an accumulation of intraluminal polyamines that promote epithelial healing. The pro-resolving effect of Arg1-deletion was reduced by an L-arginine-free diet, but rescued by simultaneous deletion of other L-arginine-metabolizing enzymes such as Arg2 or Nos2, demonstrating that protection from colitis requires L-arginine. Fecal microbiota transfers from Tie2-Cre+/-Arg1fl/fl mice into wild-type recipients ameliorated intestinal inflammation while transfers from wild-type littermates into Arg1-deficient mice prevented an advanced recovery from colitis. Thus, an increased availability of L-arginine as well as altered intestinal microbiota and metabolic products account for the accelerated resolution from colitis in the absence of Arg1. Consequently, the metabolism of L-arginine may serve as target for clinical intervention in IBD patients.

Authors

Julia Baier, Maximilian Gänsbauer, Claudia Giessler, Harald Arnold, Mercedes Muske, Ulrike Schleicher, Soeren Lukassen, Arif B. Ekici, Manfred Rauh, Christoph Daniel, Arndt Hartmann, Benjamin Schmid, Philipp Tripal, Katja Dettmer, Peter J. Oefner, Raja Atreya, Stefan Wirtz, Christian Bogdan, Jochen Mattner

The CDK4/6-EZH2 pathway is a potential therapeutic target for psoriasis

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Psoriasis is a frequent inflammatory skin disease characterized by keratinocyte hyperproliferation and a disease-related infiltration of immune cells. Here, we identified a novel pro-inflammatory signaling pathway driven by the cyclin-dependent kinases (CDK) 4 and 6 and the methyltransferase EZH2 as a valid target for psoriasis therapy. Delineation of the pathway revealed that CDK4/6 phosphorylated EZH2 in keratinocytes, thereby triggering a methylation-induced activation of STAT3. Subsequently, active STAT3 resulted in the induction of IκBζ (IkappaBzeta), which is a key pro-inflammatory transcription factor required for cytokine synthesis in psoriasis. Pharmacological or genetic inhibition of CDK4/6 or EZH2 abrogated psoriasis-related pro-inflammatory gene expression by suppressing IκBζ induction in keratinocytes. Importantly, topical application of CDK4/6 or EZH2 inhibitors on the skin was sufficient to fully prevent the development of psoriasis in various mouse models by suppressing STAT3-mediated IκBζ expression. Moreover, we found a hyperactivation of the CDK4/6-EZH2 pathway in human and mouse psoriatic skin lesions. Thus, this study not only identifies a novel psoriasis-relevant pro-inflammatory pathway, but also proposes the repurposing of CDK4/6 or EZH2 inhibitors as a new therapeutic option for psoriasis patients.

Authors

Anne Müller, Antje Dickmanns, Claudia Resch, Knut Schäkel, Stephan Hailfinger, Matthias Dobbelstein, Klaus Schulze-Osthoff, Daniela Kramer