Research
Abstract
Extracellular DNA (ecDNA) released from injured and dying cells powerfully induces injurious inflammation. In this study we define the role of ecDNA in systemic vasculitis affecting the kidney, using human kidney biopsies and murine models of myeloperoxidase anti-neutrophil cytoplasmic antibody-associated glomerulonephritis (MPO-ANCA GN). Twice daily administration of intravenous DNase I (ivDNase I) in two models of anti-MPO GN reduced glomerular deposition of ecDNA, histological injury, leukocyte infiltration and NETosis. Comprehensive investigation into DNase I modes of action revealed that after exposure to MPO, DNase I reduced lymph node DC numbers and their activation status, resulting in decreased frequency of MPO-specific CD4 effector T cells (IFN-, and IL-17A producing), and reductions in dermal anti-MPO delayed type hypersensitivity responses. To overcome the translational obstacle of the short half-life of DNase I (<5 hours), we tested an adeno-associated viral vector encoding DNase I (vec-DNase I). The method of DNase I delivery was more effective, as in addition to the histological and anti-inflammatory changes described above, a single vector treatment also reduced circulating MPO-ANCA titers and albuminuria. These results indicate ecDNA is a potent driver of anti-MPO GN and that DNase I is a potential therapeutic that can be delivered using gene technology
Authors
Anne Cao Le, Virginie Oudin, Jonathan Dick, Maliha A. Alikhan, Timothy A. Gottschalk, Lu Lu, Kate E. Lawlor, Daniel Koo Yuk Cheong, Mawj Mandwie, Ian E. Alexander, A R. Kitching, Poh-Yi Gan, Grant J. Logan, Kim M. O'Sullivan
Abstract
Mammalian skin is a vital barrier with the epidermis serving as its protective outer layer, continually undergoing renewal. Given that loss of the epidermis or its barrier function is lethal for mammals, multiple stem cell populations likely exist for the interfollicular epidermis (IFE), enhancing evolutionary survival. Here, we demonstrate that transcription factor KROX20 marks a heterogeneous stem cell population in the upper and middle mouse hair follicle (HF), partially overlapping with known HF stem cell markers in those regions. Lineage tracing in mice using different reporter lines shows that Krox20-lineage cells migrate from the HF to the IFE, contributing to both basal and suprabasal layers during adulthood. Spatial transcriptomics data corroborate our findings. Depletion of epithelial Krox20-expressing cells leads to epidermal hyperplasia and a disruption of stratification during morphogenesis and homeostasis. Our study highlights the contribution of hair follicle Krox20-lineage cells to the IFE and the regulation of epidermal homeostasis.
Authors
Elnaz Ghotbi, Edem Tchegnon, Ze Yu, Tracey Shipman, Zhiguo Chen, Yumeng Zhang, Renee M. McKay, Chao Xing, Chung-Ping Liao, Lu Q. Le
Abstract
The tumor microenvironment (TME) is highly heterogeneous and can dictate the success of therapeutic interventions. Identifying TMEs that are susceptible to specific therapeutic interventions paves the way for more personalized and effective treatments. In this study, using a spontaneous murine model of breast cancer, we characterize a TME that is responsive to inhibitors of the heme degradation pathway mediated by heme oxygenase (HO), resulting in CD8+ T- and NK-cell-dependent tumor control. A hallmark of this TME is a chronic type-I interferon (IFN) signal that is directly involved in orchestrating the anti-tumor immune response. Importantly, we identify that similar TMEs exist in human breast cancer which are associated with patient prognosis. Leveraging these observations, we demonstrate that combining a STING agonist, which induces type-I IFN responses, with an HO inhibitor produces a synergistic effect leading to superior tumor control. This study highlights HO activity as a potential resistance mechanism for type-I IFN responses in cancer offering a novel avenue for overcoming immune evasion in cancer therapy.
Authors
Dominika Sosnowska, Tik Shing Cheung, Jit Sarkar, James W. Opzoomer, Karen T. Feehan, Joanne E. Anstee, Chloé Amelia Woodman, Mohamed Reda Keddar, Kalum Clayton, Samira Ali, William Macmorland, Dorothy D. Yang, James Rosekilly, Cheryl E. Gillett, Francesca D. Ciccarelli, Richard Buus, James Spicer, Anita Grigoriadis, James N. Arnold
Abstract
Idiopathic pulmonary fibrosis (IPF) is a severe diffuse progressive fibrosing interstitial disease leading to respiratory failure and death in the absence of organ transplantation. Substantial evidence has confirmed the pivotal role of fibroblasts in the progression of IPF, yet effective therapeutic options are scarce. Single-cell transcriptomics profiling revealed that among the diverse fibroblast subsets, FAP1+ alveolar fibroblasts (AFs) are pivotal for the progression of IPF. On the basis of these findings, we developed FAP1-targeting chimeric antigen receptor cytotoxic effector regulatory T (CAR-cTregs) cells, which leverage the targeted killing advantage of the currently trending CAR-based immunotherapy for tumors and incorporate the immunosuppressive functions of Tregs to mitigate the inflammation caused by both the disease itself and CAR-T-cell infusion. Accordingly, CAR-cTregs were constructed to effectively eliminate FAP1+ fibroblasts in vitro. This cytotoxic effect can be abrogated by inhibitors of the granzyme-perforin pathway. In the bleomycin-induced PF model, CAR-cTregs were found to reverse fibrosis characterized by diminished recruitment of fibrocytes and improved remodeling of epithelial cells. Together, our results demonstrate that CAR-cTregs can serve as a promising therapeutic option for IPF and provide a novel strategy for treating multiple chronic inflammatory diseases by inducing both cytotoxicity and immunosuppression.
Authors
Yun-Han Jiang, Meng Zhou, Meng-Di Cheng, Sai Chen, Ying-Qiang Guo
Abstract
The Z variant (Glu342Lys) causes alpha1 antitrypsin (AAT) to self-assemble into polymer chains that accumulate within hepatocytes causing liver disease and exposing a cryptic epitope recognised by the 2C1 monoclonal antibody (mAb). They can be blocked by the small molecule ‘716 that stabilises an intermediate on the polymerisation pathway. We have characterised 23 mutants of AAT in a cellular model to establish: (i) their ability to form intracellular polymers; (ii) whether polymer formation could be prevented by ‘716; and (iii) whether the polymers expose the 2C1 cryptic epitope. Most of the variants, including Mprocida (Leu41Pro), Mherleen (Pro369Leu), Mduarte (Asp256Val), Lfrankfurt (Pro255Thr), Yorzinuovi (Pro391His), Mwurzburg (Pro369Ser) and p.289S accumulated as intracellular polymers. Eleven formed polymers that were resistant to ‘716, including Mprocida, Mmalton (ΔPhe51), Lfrankfurt, Mduarte, S (Glu264Val), Mherleen, and Yorzinuovi. The ‘716 resistant mutants localise to a region of the AAT molecule separate from the binding site of the small molecule and form polymers that are less well-recognised by the 2C1 mAb. They are fully recognised by a novel 8A7 mAb that we developed to have a broader specificity. Our data suggest that individuals with these mutations are unlikely to benefit from treatment with ‘716 or its derivatives.
Authors
Riccardo Ronzoni, Ibrahim F. Aldobyian, Elena Miranda, Narinder Heyer-Chauhan, Emma L.K. Elliston, Juan Pérez, Annamaria Fra, James A. Irving, David A. Lomas
Abstract
Mutations in Cullin-3 (CUL3) cause hypertension (HTN). We examined the role of smooth muscle cell (SMC) CUL3 in the regulation of renin gene expression. Mice with SMC-specific CUL3 deletion (S-CUL3KO) developed severe HTN with paradoxically preserved levels of plasma angiotensin peptides and renal renin expression. Cre-recombinase was active in JG cells resulting in decreased CUL3 expression. We evaluated components of the renin cell baroreceptor and revealed preserved lamin A/C but decreased integrin β1 expression in S-CUL3KO. We hypothesized that Rab proteins are involved in integrin β1 downregulation. Silencing either Rab21 or Rab5 in CUL3-deficient HEK293 cells increased integrin β1 protein. Co-immunoprecipitation revealed a direct interaction between Rab5 and CUL3. CUL3-deficiency increased Rab5 suggesting it is regulated by a CUL3-mediated mechanism and that CUL3-deficiency results in loss of Rab protein turnover leading to enhanced integrin β1 internalization. We conclude that the loss of integrin β1 from juxtaglomerular cells impairs the mechanosensory function of the renin cell baroreceptor, which underlies the persistent renin expression observed in hypertensive S-CUL3KO mice. These findings provide insights into the molecular mechanisms of HTN, revealing that dysregulation of Rab proteins and integrin β1 in the kidney due to CUL3-deficiency contributes to the development of HTN.
Authors
Daria Golosova, Gaurav Kumar, Ko-Ting Lu, Patricia C. Muskus Veitia, Ana Hantke Guixa, Kelsey K. Wackman, Eva M. Fekete, Daniel T. Brozoski, Justin L. Grobe, Maria Luisa S. Sequeira-Lopez, R. Ariel Gomez, Pablo Nakagawa, Curt D. Sigmund
Abstract
Hematopoietic Protein-1 (Hem1) is a component of the WASP-family verprolin-homologous protein (WAVE) actin regulatory complex, which is activated downstream of multiple immune receptors. Mutations in the NCKAP1L gene encoding HEM1 have recently been found to result in severe Primary Immunodeficiency Disease (PID), characterized by recurrent respiratory infections, hyperinflammation, autoimmunity, and high mortality. However, how loss of Hem1 results in PID is unclear. To define the importance of Hem1 specifically in T cells, we generated constitutive and T cell specific Hem1 null mice. Hem1 deficient T cells exhibited an increased shift from naïve to memory T cells, and increased ratio of immunosuppressive regulatory to effector T cells. Loss of Hem1 resulted in hallmarks of T cell exhaustion including T cell lymphopenia, decreased activation and proliferation, increased expression of PD-1 and Tim3, and increased IL-10 production. In vitro TCR stimulation of CD4 T cells resulted in increased production of Th1 (IFN), Th2 (IL-5, IL-13), Th17 (IL-17, IL-22), and Treg (IL-10) cytokines. This correlated with reduced F-actin, increased expression of CD107a, and increased granzyme release indicative of increased granule membrane fusion and exocytosis. These results suggest that Hem-1 is critical for maintaining T cell activation, homeostasis and regulated cytokine production following antigen encounter.
Authors
Alexandra Christodoulou, Nutthakarn Suwankitwat, Jacob T. Tietsort, Ryan Z. Culbert, Julia Y. Tsai, Fatima A. Tarbal, Chengsong Zhu, Brian M. Iritani
Abstract
MICB is a ligand for NKG2D. We have shown NK cells are central to lung transplant acute lung injury (ALI) via NKG2D activation, and increased MICB in bronchoalveolar lavage predicts ALI severity. Separately, we found a MICB polymorphism (MICBG406A) is associated with decreased ALI risk. We hypothesized this polymorphism would protect against severe SARS-CoV-2 respiratory disease. We analyzed 1,036 patients hospitalized with SARS-CoV-2 infection from the IMPACC cohort. Associations between MICBG406A and outcomes were determined by linear regression or Cox Proportional Hazards models. We also measured immune profiles of peripheral blood, upper and lower airway. We identified 560 major allele homozygous patients, and 426 and 50 with one or two copies of the variant allele. MICBG406A conferred reduced odds of severe COVID-19 (OR = 0.73, CI = 0.58–0.93, P = 0.04). MICBG406A homozygous participants demonstrated 34% reduced cumulative odds for mechanical ventilation or death (CI = 0.51–0.85, P = 0.005) and 43% reduced risk for mortality (CI = 0.35–0.77, P = 0.001). Patients with MICBG406A variant alleles had reduced soluble inflammatory mediators and differential regulation of multiple immune pathways. These findings demonstrate a novel association between increasing MICBG406A variant allele copies and reduced COVID-19 severity, independent of SARS-CoV-2 viral burden and humoral immunity, suggesting the NKG2D-ligand pathway as an intervention target.
Authors
Harry Pickering, Narges Alipanah-Lechner, Ernie Chen, Dylan Duchen, Holden T. Maecker, Seunghee Kim-Schulze, Ruth R. Montgomery, Chris Cotsapas, Hanno Steen, Florian Krammer, Charles R. Langelier, Ofer Levy, Lindsey R. Baden, Esther Melamed, Lauren I.R. Ehrlich, Grace A. McComsey, Rafick P. Sekaly, Charles B. Cairns, Elias K. Haddad, Albert C. Shaw, David A. Hafler, David B. Corry, Farrah Kheradmand, Mark A. Atkinson, Scott C. Brakenridge, Nelson I. Agudelo Higuita, Jordan P. Metcalf, Catherine L. Hough, William B. Messer, Bali Pulendran, Kari C. Nadeau, Mark M. Davis, Ana Fernandez-Sesma, Viviana Simon, Monica Kraft, Christian Bime, David J. Erle, Joanna Schaenman, Al Ozonoff, Bjoern Peters, Steven H. Kleinstein, Alison D. Augustine, Joann Diray-Arce, Patrice M. Becker, Nadine Rouphael, Matthew C. Altman, Steven E. Bosinger, Walter L. Eckalbar, IMPACC Network, Carolyn S. Calfee, Oscar A. Aguilar, Elaine F. Reed, John R. Greenland, Daniel R. Calabrese
Abstract
Pulmonary fibrosis (PF) is a life-threatening disease that requires effective and well-tolerated therapeutic modalities. Previously, the distinct pathogenic roles of cannabinoid receptor 1 (CB1R) and inducible nitric oxide synthase (iNOS) in the lungs and their joint therapeutic targeting were highlighted in PF. However, the cell-specific role of CB1R in PF has not been explored. Here, we demonstrate that CB1R in alveolar macrophages (AMs) mediates the release of anandamide into the alveoli, which promotes PF by inducing profibrotic macrophages that are accessible to locally delivered antifibrotic therapy. A multitargeted therapy may improve therapeutic efficacy in PF. Pulmonary delivery of 0.5 mg/kg/day MRI-1867 (zevaquenabant), a peripherally acting hybrid CB1R/iNOS inhibitor, is as effective as systemic delivery of 10 mg/kg/day, and also matches the efficacy of nintedanib in mitigating bleomycin-induced PF. A systems pharmacology approach reveals that zevaquenabant and nintedanib treatments reverse pathologic changes in both distinct and shared PF-related pathways, which are conserved in human and mouse. Moreover, zevaquenabant treatment also attenuated fibrosis and profibrotic mediators in human precision-cut lung slices. These findings establish CB1R-expressing AMs as a therapeutic target and support local delivery of dual CB1R/iNOS inhibitor zevaquenabant by inhalation as an effective, well-tolerated, and safer strategy for PF.
Authors
Abhishek Basu, Muhammad Arif, Kaelin M. Wolf, Madeline Behee, Natalie L. Johnson, Lenny Pommerolle, Ricardo H. Pineda, John Sembrat, Charles N. Zawatsky, Szabolcs Dvorácskó, Nathan J. Coffey, Joshua K. Park, Seray B. Karagoz, Grzegorz Godlewski, Tony Jourdan, Judith Harvey-White, Melanie Königshoff, Malliga R. Iyer, Resat Cinar
Abstract
Hereditary cardiomyopathies are the prototypic forms of heart failure and major causes of sudden cardiac death. The genome in cardiomyopathies is exposed to internal stressors, which damage the DNA and activate the DNA damage response (DDR) pathways. We set to determine whether the DDR pathways were activated and pathogenic in an established mouse model of desmoplakin (DSP)-cardiomyopathy generated upon deletion of the Dsp gene in cardiac myocytes (Myh6-McmTam:DspF/F). The mice exhibited premature death, cardiac dysfunction, myocardial cell death, fibrosis, and increased expression levels of the pro-inflammatory cytokines, consistent with the phenotype of human DSP-cardiomyopathy. Cytosolic nuclear self-DNA (nDNA) and mitochondrial DNA (mtDNA) were increased in cardiac myocyte cytosol in the Myh6-McmTam:DspF/F mice. Likewise, the DDR pathway proteins, including the cyclic GMP-AMP synthase (CGAS), stimulator of interferon response 1 (STING1) were upregulated as were the transcript levels of interferon response factor 3 (IRF3) and the nuclear factor κB (NFκB) target genes. Deletion of the Mb21d1 gene encoding CGAS in the Myh6-McmTam:DspF/F mice prolonged survival, improved cardiac function, attenuated fibrosis, and reduced cell death. Thus, cytosolic nDNA and mtDNA are increased and the DDR pathways are activated and pathogenic in a mouse model of DSP-cardiomyopathy, whereas genetic blockade of CGAS is salubrious.
Authors
Weiyue Wang, Benjamin Cathcart, Quoc D. Nguyen, Loi Q. Lao, Amelia Bryans, Sara E. Coleman, Leila Rouhi, Priyatansh Gurha, Ali J. Marian
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