Research
Abstract
Genetic or acquired defects of the lymphatic vasculature often result in disfiguring, disabling and, occasionally, life-threatening clinical consequences. Advanced forms of lymphedema are readily diagnosed clinically, but more subtle presentations often require invasive imaging or other technologies for a conclusive diagnosis. On the other hand, lipedema, a chronic lymphatic microvascular disease with pathological accumulation of subcutaneous adipose tissue is often misdiagnosed as obesity or lymphedema; currently there are no biomarkers or imaging criteria available for a conclusive diagnosis. Recent evidence suggests that otherwise asymptomatic defective lymphatic vasculature likely contributes to an array of other pathologies, including obesity, inflammatory bowel disease and neurological disorders, among others. Accordingly, identification of biomarkers of lymphatic malfunction will provide a valuable resource for the diagnosis and clinical discrimination of lymphedema, lipedema, obesity and other potential lymphatic-related pathologies. In this paper we profiled and compared blood plasma exosomes isolated from mouse models and from human subjects with and without symptomatic lymphatic pathologies. We identified platelet factor 4 (PF4/CXCL4) as a biomarker that could be used to diagnose lymphatic vasculature dysfunction. Furthermore, we determined that PF4 levels in circulating blood plasma exosomes were also elevated in lipedema patients, supporting current claims arguing that at least some of the underlying attributes of this disease are also the consequence of lymphatic defects.
Authors
Wanshu Ma, Hyea Jin Gil, Noelia Escobedo, Alberto Benito-Martín, Pilar Ximénez-Embún, Javier Muñoz, Héctor Peinado, Stanley G. Rockson, Guillermo Oliver
Abstract
Spinal muscular atrophy (SMA) is an inherited neuromuscular disorder caused by reduced expression of the survival motor neuron (SMN) protein. SMN has key functions in multiple RNA pathways, including the biogenesis of small nuclear ribonucleoproteins (snRNPs) that are essential components of both major (U2-dependent) and minor (U12-dependent) spliceosomes. Here we investigated the specific contribution of U12 splicing dysfunction to SMA pathology through selective restoration of this RNA pathway in mouse models of varying phenotypic severity. We show that viral-mediated delivery of minor snRNA genes specifically improves select U12 splicing defects induced by SMN deficiency in cultured mammalian cells as well as in the spinal cord and dorsal root ganglia of SMA mice without increasing SMN expression. This approach resulted in a moderate amelioration of several parameters of the disease phenotype in SMA mice including survival, weight gain and motor function. Importantly, minor snRNA gene delivery improved aberrant splicing of the U12 intron-containing gene Stasimon and rescued the severe loss of proprioceptive sensory synapses on SMA motor neurons, which are early signatures of motor circuit dysfunction in mouse models. Taken together, these findings establish the direct contribution of U12 splicing dysfunction to synaptic deafferentation and motor circuit pathology in SMA.
Authors
Erkan Y. Osman, Meaghan Van Alstyne, Pei-Fen Yen, Francesco Lotti, Zhihua Feng, Karen K.Y. Ling, Chien-Ping Ko, Livio Pellizzoni, Christian L. Lorson
Abstract
Increased microvascular leakage is a cardinal feature of many critical diseases. Regular exercise is associated with improved endothelial function and reduced risk of cardiovascular disease. Irisin, secreted during exercise, contributes to many health benefits of exercise. However, the effects of irisin on endothelial function and microvascular leakage remain unknown. In this study, we found that irisin remarkably strengthened endothelial junctions and barrier function via binding to integrin αVβ5 receptor in LPS-treated endothelial cells. The beneficial effect of irisin was associated with suppression of the Src-MLCK-β-catenin pathway, activation of the AMPK-Cdc42/Rac1 pathway and improvement of mitochondrial function. In preclinical models of microvascular leakage, exogenous irisin improved pulmonary function, decreased lung edema and injury, suppressed inflammation, and increased survival. In ARDS patients, serum irisin levels were decreased and inversely correlated with disease severity and mortality. In conclusion, irisin enhances endothelial barrier function and mitigates microvascular leakage related diseases.
Authors
Jianbin Bi, Jia Zhang, Yifan Ren, Zhaoqing Du, Yuanyuan Zhang, Chang Liu, Yawen Wang, Lin Zhang, Zhihong Shi, Zheng Wu, Yi Lv, Rongqian Wu
Abstract
Apelin is a well-established mediator of survival and mitogenic signalling through apelin receptor (Aplnr) and have been implicated in various cancers, however little is known regarding Elabela (ELA/APELA) signalling, also mediated by Aplnr, and its role and the role of the conversion of its precursor proELA into mature ELA in cancer are unknown. Here we identify a function of mTORC1 signalling as an essential mediator of ELA that represses kidney tumour cells growth, migration and survival. Moreover, sunitinib and ELA show synergistic effect in repressing tumour growth and angiogenesis in mice. The use of site directed mutagenesis and pharmacologic experiments provide evidence that the alteration of the cleavage site of proELA by Furin induced improved ELA anti-tumorigenic activity. Finally, cohort of tumours and public data sets revealed that ELA is only repressed in the main human kidney cancer subtypes namely clear cell, papillary, and chromophobe renal cell carcinoma. While Aplnr is expressed by various kidney cells, ELA is generally expressed by epithelial cells. Collectively, these results show the tumour-suppressive role of mTORC1 signalling mediated by ELA and establish the potential use of ELA or derivatives in kidney cancers treatment.
Authors
Fabienne Soulet, Clement Bodineau, Katarzyna B. Hooks, Jean Descarpentrie, Isabel D. Alves, Marielle Dubreuil, Amandine Mouchard, Malaurie Eugenie, Jean-Luc Hoepffner, José Javier Lopez, Juan A. Rosado, Isabelle Soubeyran, Mercedes Tomé, Raúl V. Durán, Macha Nikolski, Bruno O. Villoutreix, Serge Evrard, Geraldine Siegfried, Abdel-Majid Khatib
Abstract
Background Identifying immune correlates of COVID-19 disease severity is an urgent need for clinical management, vaccine evaluation and drug development. Here we present a temporal analysis of key immune mediators, cytokine and chemokines in blood of hospitalised COVID-19 patients from serial sampling and follow up over four weeks. Methods A total of 71 patients with laboratory-confirmed COVID-19 admitted to Beijing You’an hospital in China with either mild (53 patients) or severe disease (18 patients) were enrolled with 18 healthy volunteers. We measured 34 immune mediators, cytokines and chemokines in peripheral blood every 4-7 days over one month per patient using a bio-plex multiplex immunoassay. Results We found that the chemokine RANTES(CCL5) was significantly elevated, from an early stage of the infection, in patients with mild but not severe disease. We also found that early production of inhibitory mediators including IL-10 and IL-1RA were significantly associated with disease severity, and a combination of CCL5, IL-1Ra and IL-10 at week 1 may predict patient outcomes. The majority of cytokines that are known to be associated with the cytokine storm in virus infections such as IL-6 and IFN-gamma were only significantly elevated in the late stage of severe COVID-19 illness. TNF- alpha and GM-CSF showed no significant differences between severe and mild cases. Conclusion Together our data suggest early intervention to increase expression of CCL5 may prevent patients from developing severe illness. Our data also suggest that measurement of levels of CCL5, as well as IL-1Ra, IL-10 in blood individually and in combination might be useful prognostic bio-markers to guide treatment strategies.
Authors
Yan Zhao, Ling Qin, Ping Zhang, Kang Li, Lianchun Liang, Jianping Sun, Bin Xu, Yanchao Dai, Xuemei Li, Chi Zhang, Yanchun Peng, Yingmei Feng, Ang Li, Zhongjie Hu, Haiping Xiang, Graham Ogg, Ling-Pei Ho, Andrew J. McMichael, Ronghua Jin, Julian C. Knight, Tao Dong, Yonghong Zhang
Activation of CAR and non-CAR T cells within the tumor microenvironment following CAR T-cell therapy
Abstract
The mechanisms of CAR-T cell mediated anti-tumor immunity and toxicity remain poorly characterized due to few studies examining the intact tumor microenvironment (TME) following CAR T-cell infusion. Axicabtagene ciloleucel is an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy approved for patients with large B-cell lymphoma. We devised multiplex immunostaining and in-situ hybridization assays to interrogate CAR T cells and other immune cell infiltrates in biopsies of diffuse large B-cell lymphoma following axicabtagene ciloleucel infusion. We found a majority of intratumoral CAR T cells expressed markers of T-cell activation but, unexpectedly, comprised ≤ 5% of all T cells within the TME five days or more after therapy. T cells lacking CAR (non-CAR T cells) were also activated within the TME after axicabtagene ciloleucel infusion, being positive for Ki-67, interferon-γ, granzyme B and/or PD-1, and highest in biopsies with CAR T cells. Additionally, non-CAR immune cells were the exclusive source of IL-6, a cytokine associated with cytokine release syndrome, and highest in biopsies with CAR T cells. These data indicate that intratumoral CAR T cells are associated with generalized immune cell activation within the TME with both beneficial and pathological effects.
Authors
Pei-Hsuan Chen, Mikel Lipschitz, Jason L. Weirather, Caron Jacobson, Philippe Armand, Kyle Wright, F. Stephen Hodi, Zachary J. Roberts, Stuart A. Sievers, John Rossi, Adrian Bot, William Y. Go, Scott J. Rodig
Abstract
Heterotopic ossification (HO) is defined as abnormal differentiation of local stromal cells of mesenchymal origin resulting in pathologic cartilage and bone matrix deposition. CCN family members are matricellular proteins that have diverse regulatory functions on cell proliferation and differentiation, including the regulation of chondrogenesis. However, little is known regarding CCN family member expression or function in HO. Here, a combination of bulk and single cell RNA sequencing defined the dynamic temporospatial pattern of CCN family member induction within a mouse model of trauma-induced HO. Among CCN family proteins, Wisp1(also known as Ccn4) was most upregulated during the evolution of HO, and Wisp1 expression corresponded with chondrogenic gene profile. Immunohistochemistry confirmed WISP1/CCN4 expression across traumatic and genetic HO mouse models, as well as in human HO samples. Transgenic Wisp1LacZ/LacZ knockin animals showed an increase in endochondral ossification in HO after trauma. Finally, the transcriptome of Wisp1 null tenocytes revealed enrichment in signaling pathways such as STAT3 and PCP signaling that may explain increased HO in the context of Wisp1 deficiency. In sum, CCN family members, and in particular Wisp1, are spatiotemporally associated with and negatively regulate trauma-induced HO formation.
Authors
Ginny Ching-Yun Hsu, Simone Marini, Stefano Negri, Yiyun Wang, Jiajia Xu, Chase A. Pagani, Charles Hwang, David M. Stepien, Carolyn A. Meyers, Sarah Miller, Edward McCarthy, Karen M. Lyons, Benjamin Levi, Aaron W. James
Abstract
Rheumatoid arthritis (RA) is characterized by synovial joint inflammation, cartilage damage and dysregulation of the adaptive immune system. While neutrophil extracellular traps (NETs) have been proposed to play a role in the generation of modified autoantigens and in the activation of synovial fibroblasts, it remains unknown whether NETs are directly involved in cartilage damage. Here, we report a new mechanism by which NET-derived elastase disrupts cartilage matrix and induces release membrane-bound peptidylarginine deiminase-2 (PAD2) by fibroblast-like synoviocytes (FLS). Cartilage fragments are subsequently citrullinated, internalized by FLS, and then presented to antigen-specific CD4+ T cells. Furthermore, immune-complexes containing citrullinated cartilage components can activate macrophages to release pro-inflammatory cytokines. HLA-DRB1*04:01 transgenic mice immunized with NETs develop autoantibodies to citrullinated cartilage proteins and display enhanced cartilage damage. Inhibition of NET-elastase rescues NET-mediated cartilage damage. These results show that NETs and neutrophil elastase externalized in these structures play fundamental pathogenic roles in promoting cartilage damage and synovial inflammation. Strategies targeting neutrophil elastase and NETs could have a therapeutic role in RA and in other inflammatory diseases associated with inflammatory joint damage.
Authors
Carmelo Carmona-Rivera, Philip M. Carlucci, Rishi R. Goel, Eddie A. James, Stephen R. Brooks, Cliff R. Rims, Victoria Hoffmann, David A. Fox, Jane H. Buckner, Mariana J. Kaplan
Abstract
Whole sporozoite vaccines engender sterilizing immunity against malaria in animal models and importantly, in humans. Gene editing allows for the removal of specific parasite genes, enabling generation of genetically attenuated parasite (GAP) strains for vaccination. Using rodent malaria parasites, we have previously shown that late liver stage-arresting replication-competent (LARC) GAPs confer superior protection when compared to early liver stage-arresting replication-deficient (EARD) GAPs and radiation-attenuated sporozoites. However, generating a LARC GAP in the human malaria parasite Plasmodium falciparum (Pf) has been challenging. Here we report the generation and characterization of an unprecedented Pf LARC GAP generated by targeted gene deletion of the Mei2 gene; Pf mei2–. Robust exoerythrocytic schizogony with extensive cell growth and DNA replication was observed for Pf mei2- liver stages in human liver-chimeric mice. However, Pf mei2– liver stages failed to complete development and did not form infectious exo-erythrocytic merozoites, thereby preventing their transition to asexual blood stage infection. Therefore, Pf mei2– is a replication-competent, attenuated human malaria parasite strain with potentially increased potency, useful for vaccination to protect against Pf malaria infection.
Authors
Debashree Goswami, William Betz, Navin K. Locham, Chaitra Parthiban, Carolyn Brager, Carola Schäfer, Nelly Camargo, Thao Nguyen, Spencer Y. Kennedy, Sean C. Murphy, Ashley M. Vaughan, Stefan H.I. Kappe
Abstract
Acute gastrointestinal Graft-versus-Host-Disease (GVHD) is a primary determinant of mortality after allogeneic hematopoietic stem-cell transplantation (alloSCT). It is mediated by alloreactive donor CD4+ T cells that differentiate into pathogenic subsets expressing IFNγ, IL-17A or GM-CSF, and is regulated by subsets expressing IL-10 and/or Foxp3. Developmental relationships between T-helper states during priming in mesenteric lymph nodes (mLN) and effector function in the GI tract remain undefined at genome-scale. We applied scRNA-seq and computational modelling to a mouse model of donor DC-mediated GVHD exacerbation, creating an atlas of putative CD4+ T-cell differentiation pathways in vivo. Computational trajectory inference suggested emergence of pathogenic and regulatory states along a single developmental trajectory in mLN. Importantly, we inferred an unexpected second trajectory, categorised by little proliferation or cytokine expression, reduced glycolysis, and high tcf7 expression. TCF1hi cells upregulated α4β7 prior to gut migration and failed to express cytokines therein. Nevertheless, they exhibited recall potential and plasticity following secondary transplantation, including cytokine or Foxp3 expression, but reduced TCF1. Thus, scRNA-seq suggested divergence of allo-reactive CD4+ T cells into quiescent and effector states during gut GVHD exacerbation by donor DC, reflecting putative heterogenous priming in vivo. These findings, the first at a single-cell level during GVHD over time, may assist in examination of T cell differentiation in patients undergoing alloSCT.
Authors
Jessica A. Engel, Hyun Jae Lee, Cameron G. Williams, Rachel D. Kuns, Stuart Olver, Lianne I.M. Lansink, Megan S.F. Soon, Stacey B. Andersen, Joseph E. Powell, Valentine Svensson, Sarah A. Teichmann, Geoffrey R. Hill, Antiopi Varelias, Motoko Koyama, Ashraful Haque
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