Gastrointestinal graft-versus-host disease (GvHD) is a major cause of mortality and morbidity following allogeneic bone marrow transplantation (allo-BMT). Chemerin is a chemotactic protein that recruits leukocytes to inflamed tissues by interacting with ChemR23/CMKLR1, a chemotactic receptor expressed by leukocytes, including macrophages. During acute GvHD, chemerin plasma levels were strongly increased in allo-BM-transplanted mice. The role of the chemerin/CMKLR1 axis in GvHD was investigated using Cmklr1-KO mice. WT mice transplanted with an allogeneic graft from Cmklr1-KO donors (t-KO) had worse survival and more severe GvHD. Histological analysis demonstrated that the gastrointestinal tract was the organ mostly affected by GvHD in t-KO mice. The severe colitis of t-KO mice was characterized by massive neutrophil infiltration and tissue damage associated with bacterial translocation and exacerbated inflammation. Similarly, Cmklr1-KO recipient mice showed increased intestinal pathology in both allogeneic transplant and dextran sulfate sodium–induced colitis. Notably, the adoptive transfer of WT monocytes into t-KO mice mitigated GvHD manifestations by decreasing gut inflammation and T cell activation. In patients, higher chemerin serum levels were predictive of GvHD development. Overall, these results suggest that CMKLR1/chemerin may be a protective pathway for the control of intestinal inflammation and tissue damage in GvHD.
Erica Dander, Paola Vinci, Stefania Vetrano, Camilla Recordati, Rocco Piazza, Grazia Fazio, Donatella Bardelli, Mattia Bugatti, Francesca Sozio, Andrea Piontini, Sonia Bonanomi, Luca Bertola, Elena Tassistro, Maria Grazia Valsecchi, Stefano Calza, William Vermi, Andrea Biondi, Annalisa Del Prete, Silvano Sozzani, Giovanna D’Amico
Collectin-11 (CL-11) is a recently described soluble C-type lectin that has distinct roles in embryonic development, host defence, autoimmunity, and fibrosis. Here we report that CL-11 also plays an important role in cancer cell proliferation and tumor growth. Melanoma growth was found to be suppressed in Colec11–/– mice in a s.c. B16 melanoma model. Cellular and molecular analyses revealed that CL-11 is essential for melanoma cell proliferation, angiogenesis, establishment of more immunosuppressive tumor microenvironment, and the reprogramming of macrophages to M2 phenotype within melanomas. In vitro analysis revealed that CL-11 can activate tyrosine kinase receptors (EGFR, HER3) and ERK, JNK, and AKT signaling pathways and has a direct stimulatory effect on murine melanoma cell proliferation. Furthermore, blockade of CL-11 (treatment with L-fucose) inhibited melanoma growth in mice. Analysis of open data sets revealed that COLEC11 gene expression is upregulated in human melanomas and that high COLEC11 expression has a trend toward poor survival. CL-11 also had direct stimulatory effects on human tumor cell proliferation in melanoma and several other types of cancer cells in vitro. Overall, our findings provide the first evidence to our knowledge that CL-11 is a key tumor growth–promoting protein and a promising therapeutic target in tumor growth.
Jia-Xing Wang, Bo Cao, Ning Ma, Kun-Yi Wu, Wan-Bing Chen, Weiju Wu, Xia Dong, Cheng-Fei Liu, Ya-Feng Gao, Teng-Yue Diao, Xiao-Yun Min, Qing Yong, Zong-Fang Li, Wuding Zhou, Ke Li
WHIM syndrome is an inherited immune disorder caused by an autosomal dominant heterozygous mutation in CXCR4. The disease is characterized by neutropenia/leukopenia (secondary to retention of mature neutrophils in bone marrow), recurrent bacterial infections, treatment-refractory warts, and hypogammaglobulinemia. All mutations reported in WHIM patients lead to the truncations in the C-terminal domain of CXCR4, R334X being the most frequent. This defect prevents receptor internalization and enhances both calcium mobilization and ERK phosphorylation, resulting in increased chemotaxis in response to the unique ligand CXCL12. Here, we describe 3 patients presenting neutropenia and myelokathexis, but normal lymphocyte count and immunoglobulin levels, carrying what we believe to be a novel Leu317fsX3 mutation in CXCR4, leading to a complete truncation of its intracellular tail. The analysis of the L317fsX3 mutation in cells derived from patients and in vitro cellular models reveals unique signaling features in comparison with R334X mutation. The L317fsX3 mutation impairs CXCR4 downregulation and β-arrestin recruitment in response to CXCL12 and reduces other signaling events — including ERK1/2 phosphorylation, calcium mobilization, and chemotaxis — all processes that are typically enhanced in cells carrying the R334X mutation. Our findings suggest that, overall, the L317fsX3 mutation may be causative of a form of WHIM syndrome not associated with an augmented CXCR4 response to CXCL12.
Rajesh Kumar, Samantha Milanesi, Martyna Szpakowska, Laura Dotta, Dario Di Silvestre, Anna Maria Trotta, Anna Maria Bello, Mauro Giacomelli, Manuela Benedito, Joana Azevedo, Alexandra Pereira, Emilia Cortesao, Alessandro Vacchini, Alessandra Castagna, Marinella Pinelli, Daniele Moratto, Raffaella Bonecchi, Massimo Locati, Stefania Scala, Andy Chevigné, Elena M. Borroni, Raffaele Badolato
Primary Sjogren’s syndrome (pSS) is a systemic autoimmune inflammatory disease mainly defined by T cell–dominated destruction of exocrine glands. Currently, CD8+T cells were closely related to the pathogenesis of pSS. However, the single-cell immune profiling of pSS and molecular signatures of pathogenic CD8+T cells have not been well elucidated. Our multiomics investigation identified that both T cell and B cell, especially CD8+T cells, were undergoing significant clonal expansion in pSS patients. TCR clonality analysis revealed that peripheral granzyme (GZM) K+CXCR6+CD8+T cells had higher proportion of shared clones with CD69+CD103-CD8+ tissue resident memory T (TRM) cells in labial glands in pSS. CD69+CD103-CD8+TRM cells featured by high expression of GZMK were more active and cytotoxic in pSS compared with their CD103+ counterparts. Peripheral GZMK+CXCR6+CD8+T cells with higher CD122 expression were increased and harbored a gene signature similar to TRM cells in pSS. Consistently, IL-15 was significantly elevated in pSS plasma and showed the capacity to promote differentiation of CD8+T cells into GZMK+CXCR6+CD8+T cells in a STAT5 dependent manner. Taken together, we depicted the immune landscape of pSS and further conducted comprehensive bioinformatics analysis and in vitro experimental investigation to characterize the pathogenic role and differentiation trajectory of CD8+TRM cells in pSS.
Ting Xu, Hao-Xian Zhu, Xing You, Jin-Fen Ma, Xin Li, Pan-Yue Luo, Yang Li, Zhe-Xiong Lian, Cai-Yue Gao
BACKGROUND. After its introduction as standard-of-care for severe COVID-19, dexamethasone has been administered to a large number of patients globally. Detailed knowledge of its impact on the cellular and humoral immune response to SARS-CoV-2 remains scarce. METHODS. We included immunocompetent individuals with 1) mild COVID-19, 2) severe COVID-19 before introduction of dexamethasone treatment, and 3) severe COVID-19 infection treated with dexamethasone from prospective observational cohort studies at Charité-Universitätsmedizin Berlin, Germany. We analyzed SARS-CoV-2 spike-reactive T cells, spike-specific IgG titers as well as serum neutralizing activity against B.1.1.7, B.1.617.2 in samples ranging from two weeks to six months post infection. We also analyzed BA.2 neutralization in sera after booster immunization. RESULTS. Patients with severe COVID-19 and dexamethasone treatment had lower T cell and antibody responses to SARS-CoV-2 compared to patients without dexamethasone treatment in the early phase of disease, which converged in both groups before six months post infection and also post-immunization. Patients with mild COVID-19 had a comparatively lower T cell and antibody response than patients with severe disease, including a lower response to booster-immunization during convalescence. CONCLUSION. Dexamethasone treatment is associated with short-term reduction of T cell and antibody response in severe COVID-19 when compared to the non-treated group, but this difference evens out six months after infection. We confirm higher cellular and humoral immune responses in patients after severe versus mild COVID-19 infection and the concept of improved hybrid immunity upon immunization. TRIAL REGISTRATION.: n/aFunding: Berlin Institute of Health, German Federal Ministry of Education and German Federal Institute for Drugs and Medical Devices
Charlotte Thibeault, Lara Bardtke, Kanika Vanshylla, Veronica Cristianzano, Kirsten A. Eberhardt, Paula Stubbemann, David Hillus, Pinkus Tober-Lau, Parnika Mukherjee, Friederike Münn, Lena J Lippert, Elisa T. Helbig, Tilman Lingscheid, Fridolin Steinbeis, Mirja Mittermaier, Martin Witzenrath, Thomas Zoller, Florian Klein, Leif E. Sander, Florian Kurth
This study aimed to enhance anti-tumor immune responses to pancreatic cancer via antibody-based blockade of IL-6 and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4). Mice bearing subcutaneous or orthotopic pancreatic tumors were treated with blocking antibodies to IL 6 and/or CTLA-4. In both tumor models, dual IL-6 and CTLA-4 blockade significantly inhibited tumor growth. Additional investigations revealed that dual therapy induced an overwhelming infiltration of T cells into the tumor as well as changes in CD4+ T cell subsets. Dual blockade therapy elicited CD4+ T cells to secrete increased IFN-γ in vitro. Likewise, in vitro stimulation of pancreatic tumor cells with IFN-γ profoundly increased tumor cell production of CXCR3 specific chemokines, even in the presence of IL-6. In vivo blockade of CXCR3 prevented orthotopic tumor regression in the presence of the combination treatment, demonstrating a dependence on the CXCR3 axis for anti-tumor efficacy. Both CD4+ and CD8+ T cells were required for the anti-tumor activity of this combination therapy, as their in vivo depletion via antibodies impaired outcomes. These data represent the first report of IL-6 and CTLA 4 blockade as a means to regress pancreatic tumors with defined operative mechanisms of efficacy. Given these results, this therapeutic combination has potential for immediate clinical translation.
Michael Brandon Ware, Maggie Phillips, Christopher McQuinn, Mohammad Y. Zaidi, Hannah M. Knochelmann, Emily Greene, Brian S. Robinson, Cameron J. Herting, Thomas A. Mace, Zhengjia Chen, Chao Zhang, Matthew R. Farren, Amanda N. Ruggieri, Jacob S. Bowers, Reena Shakya, Alton Brad Farris, Gregory Young, William E. Carson III, Bassel El-Rayes, Chrystal M. Paulos, Gregory B. Lesinski
Multiple randomized, controlled clinical trials have yielded discordant results regarding the efficacy of convalescent plasma in outpatients, with some showing an approximate two-fold reduction in risk and others showing no effect. We quantified binding and neutralizing antibody levels in 492 of the 511 participants from the C3PO trial of a single unit of COVID-19 convalescent plasma (CCP) vs. saline infusion. In a subset of 70 participants, peripheral blood mononuclear cells were obtained to define the evolution of B and T cell responses through day 30. Binding and neutralizing antibody responses were measurably higher one hour post-infusion in recipients of CCP compared to saline plus multivitamin, but levels achieved by the native immune system by day 15 were much higher than seen immediately after CCP administration. Infusion of CCP did not block generation of the host antibody response or skew B or T cell phenotype or maturation. Activated CD4+ and CD8+ T cells were associated with more severe disease outcome. These data show that CCP leads to a measurable boost in anti-SARS-CoV-2 antibodies, but that the boost is modest and may not be sufficient to alter disease course.
John F. McDyer, Mahzad Azimpouran, Valerie L. Durkalski-Mauldin, Robert G. Clevenger, Sharon D. Yeatts, Xutao Deng, William Barsan, Robert Silbergleit, Nahed El Kassar, Iulia Popescu, Dimiter Dimitrov, Wei Li, Emily J. Lyons, Sophia C. Lieber, Mars Stone, Frederick K. Korley, Clifton W. Callaway, Larry J. Dumont, Philip J. Norris
Sosuga virus (SOSV) is a recently discovered paramyxovirus with a single known human case of disease. There has been little laboratory research on SOSV pathogenesis or immunity, and no approved therapeutics or vaccines are available. Here, we report the discovery of human monoclonal antibodies (mAbs) from the circulating memory B cells of the only known human case and survivor of SOSV infection. We isolated six mAbs recognizing the functional attachment protein hemagglutinin-neuraminidase (HN) and 18 mAbs against the fusion (F) protein. The anti-HN mAbs all target the globular head of the HN protein and can be organized into 4 competition-binding groups that exhibit epitope diversity. The anti-F mAbs can be divided into pre- or postfusion conformation-specific categories and further into 8 competition-binding groups. The only antibody in the panel that did not display neutralization activity was the single, postfusion-specific anti-F mAb. Most of the anti-HN mAbs were more potently neutralizing than the anti-F mAbs, with mAbs in one of the HN competition-binding groups possessing ultra-potent (<1 ng/mL) half maximal inhibitory (IC50) virus neutralization values. These findings provide insight into the molecular basis for human antibody recognition of paramyxovirus surface proteins and the mechanisms of SOSV neutralization.
Helen M. Parrington, Nurgun Kose, Erica Armstrong, Laura S. Handal, Summer Diaz, Joseph Reidy, Jinhui Dong, Guillaume B.E. Stewart-Jones, Punya Shrivastava-Ranjan, Shilpi Jain, César G. Albariño, Robert H. Carnahan, James E. Crowe
Pulmonary fibrosis is potentiated by a positive feedback loop involving the extracellular sialidase enzyme NEU3 causing release of active TGF-β1, and TGF-β1 upregulating NEU3 by increasing translation without affecting mRNA levels. In this report, we elucidate the TGF-β1 upregulation of translation mechanism. In human lung fibroblasts, TGF-β1 increased levels of proteins, including NEU3, by increasing translation of the encoding mRNAs without significantly affecting levels of these mRNAs. 180 of these mRNAs share a common 20 nucleotide motif. Deletion of this motif from NEU3 mRNA eliminated the TGF-β1 upregulation of NEU3 translation, while insertion of this motif in two mRNAs insensitive to TGF-β1 caused TGF-β1 to upregulate their translation. RNA-binding proteins including DDX3 bind the RNA motif, and TGF-β1 regulates their protein levels and/or binding to the motif. We found that DDX3 is upregulated in the fibrotic lesions in pulmonary fibrosis patients, and inhibiting DDX3 in fibroblasts reduced TGF-β1 upregulation of NEU3 levels. In the mouse bleomycin model of pulmonary fibrosis, injections of the DDX3 inhibitor RK-33 potentiated survival and reduced lung inflammation, fibrosis, and lung tissue levels of DDX3, TGF-β1, and NEU3. These results suggest that inhibiting a mRNA-binding protein that mediates TGF-β1 upregulation of translation can reduce pulmonary fibrosis.
Wensheng Chen, Darrell Pilling, Richard H. Gomer
HIV-1 usually utilize CCR5 as the co-receptor and rarely switches to CXCR4-tropic until late stage of infection. CCR5+CD4+ T cells are the major virus-producing cells in viremic patients as well as SIV-infected non-human primates. The differentiation of CCR5+CD4+ T cells is associated with the availability of IL15, which increases during acute HIV-1 infection. Here, we report that CCR5 is expressed by CD4+ T cells exhibiting effector or effector memory phenotype with high expression levels of the IL2/IL15 receptor common beta and gamma chains. IL15 but not IL7 improves the survival of CCR5+CD4+ T cells, drives their expansion, and facilitates HIV-1 infection in vitro and in humanized mice. Our study suggests that IL15 plays confounding roles in HIV-1 infection, and future studies on the IL15-based boosting of anti-HIV-1 immunity should carefully exam the potential effects on the expansion of HIV-1 reservoirs in CCR5+CD4+ T cells.
Yuhao Li, Hongbo Gao, Kolin M. Clark, Liang Shan
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