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1.
Cell ; 186(23): 5098-5113.e19, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37918395

RESUMO

Drug-resistant Pseudomonas aeruginosa (PA) poses an emerging threat to human health with urgent need for alternative therapeutic approaches. Here, we deciphered the B cell and antibody response to the virulence-associated type III secretion system (T3SS) in a cohort of patients chronically infected with PA. Single-cell analytics revealed a diverse B cell receptor repertoire directed against the T3SS needle-tip protein PcrV, enabling the production of monoclonal antibodies (mAbs) abrogating T3SS-mediated cytotoxicity. Mechanistic studies involving cryoelectron microscopy identified a surface-exposed C-terminal PcrV epitope as the target of highly neutralizing mAbs with broad activity against drug-resistant PA isolates. These anti-PcrV mAbs were as effective as treatment with conventional antibiotics in vivo. Our study reveals that chronically infected patients represent a source of neutralizing antibodies, which can be exploited as therapeutics against PA.


Assuntos
Anticorpos Antibacterianos , Anticorpos Neutralizantes , Infecções por Pseudomonas , Pseudomonas aeruginosa , Humanos , Anticorpos Antibacterianos/farmacologia , Microscopia Crioeletrônica , Imunoglobulinas/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Infecções por Pseudomonas/tratamento farmacológico
3.
Mol Syst Biol ; 18(9): e11256, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36094010

RESUMO

Cells of the innate immune system represent the first line of defense against SARS-CoV-2 and play an essential role in activating adaptive immunity, which mediates long-term protection. In addition, the same cells are key drivers of tissue damage by causing the hyperinflammatory state and cytokine storm that makes COVID-19 a deadly disease. Thus, careful dissection of the host-pathogen interaction on a cellular level is essential to understanding SARS-CoV-2 pathogenesis and developing new treatment modalities against COVID-19. In their recent work, Goffinet and colleagues (Kazmierski et al, 2022) investigate the cell-intrinsic responses of human primary peripheral blood mononuclear cells (PBMCs) exposed to SARS coronaviruses.


Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Humanos , Imunidade Inata , Interferons , Leucócitos Mononucleares , Monócitos
4.
PLoS Pathog ; 16(7): e1008560, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32667948

RESUMO

Human cytomegalovirus (HCMV) causes serious complications to immune compromised hosts. Dendritic cells (iDCgB) expressing granulocyte-macrophage colony-stimulating factor, interferon-alpha and HCMV-gB were developed to promote de novo antiviral adaptive responses. Mice reconstituted with a human immune system (HIS) were immunized with iDCgB and challenged with HCMV, resulting into 93% protection. Immunization stimulated the expansion of functional effector memory CD8+ and CD4+ T cells recognizing gB. Machine learning analyses confirmed bone marrow T/CD4+, liver B/IgA+ and spleen B/IgG+ cells as predictive biomarkers of immunization (≈87% accuracy). CD8+ and CD4+ T cell responses against gB were validated. Splenic gB-binding IgM-/IgG+ B cells were sorted and analyzed at a single cell level. iDCgB immunizations elicited human-like IgG responses with a broad usage of various IgG heavy chain V gene segments harboring variable levels of somatic hypermutation. From this search, two gB-binding human monoclonal IgGs were generated that neutralized HCMV infection in vitro. Passive immunization with these antibodies provided proof-of-concept evidence of protection against HCMV infection. This HIS/HCMV in vivo model system supported the validation of novel active and passive immune therapies for future clinical translation.


Assuntos
Anticorpos Antivirais/imunologia , Infecções por Citomegalovirus/imunologia , Vacinas contra Citomegalovirus/imunologia , Imunização Passiva , Imunoglobulina G/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/farmacologia , Antígenos Virais/imunologia , Citomegalovirus/imunologia , Células Dendríticas/imunologia , Modelos Animais de Doenças , Humanos , Imunoglobulina G/farmacologia , Camundongos
5.
Am J Pathol ; 189(3): 521-539, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30593822

RESUMO

Humanized mice developing functional human T cells endogenously and capable of recognizing cognate human leukocyte antigen-matched tumors are emerging as relevant models for studying human immuno-oncology in vivo. Herein, mice transplanted with human CD34+ stem cells and bearing endogenously developed human T cells for >15 weeks were infected with an oncogenic recombinant Epstein-Barr virus (EBV), encoding enhanced firefly luciferase and green fluorescent protein. EBV-firefly luciferase was detectable 1 week after infection by noninvasive optical imaging in the spleen, from where it spread rapidly and systemically. EBV infection resulted into a pronounced immunologic skewing regarding the expansion of CD8+ T cells in the blood outnumbering the CD4+ T and CD19+ B cells. Furthermore, within 10 weeks of infections, mice developing EBV-induced tumors had significantly higher absolute numbers of CD8+ T cells in lymphatic tissues than mice controlling tumor development. Tumor outgrowth was paralleled by an up-regulation of the programmed cell death receptor 1 on CD8+ and CD4+ T cells, indicative for T-cell dysfunction. Histopathological examinations and in situ hybridizations for EBV in tumors, spleen, liver, and kidney revealed foci of EBV-infected cells in perivascular regions in close association with programmed cell death receptor 1-positive infiltrating lymphocytes. The strong spatiotemporal correlation between tumor development and the T-cell dysfunctional status seen in this viral oncogenesis humanized model replicates observations obtained in the clinical setting.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Herpesvirus Humano 4/imunologia , Proteínas de Neoplasias/imunologia , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/imunologia , Animais , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Infecções por Vírus Epstein-Barr/patologia , Humanos , Ativação Linfocitária , Camundongos , Camundongos Mutantes , Neoplasias/patologia , Neoplasias/virologia
6.
Am J Pathol ; 187(6): 1380-1398, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28432872

RESUMO

Humanized mice engrafted with human hematopoietic stem cells and developing functional human T-cell adaptive responses are in critical demand to test human-specific therapeutics. We previously showed that humanized mice immunized with long-lived induced-dendritic cells loaded with the pp65 viral antigen (iDCpp65) exhibited a faster development and maturation of T cells. Herein, we evaluated these effects in a long-term (36 weeks) nonclinical model using two stem cell donors to assess efficacy and safety. Relative to baseline, iDCpp65 immunization boosted the output of effector memory CD4+ T cells in peripheral blood and lymph nodes. No weight loss, human malignancies, or systemic graft-versus-host (GVH) disease were observed. However, for one reconstitution cohort, some mice immunized with iDCpp65 showed GVH-like signs on the skin. Histopathology analyses of the inflamed skin revealed intrafollicular and perifollicular human CD4+ cells near F4/80+ mouse macrophages around hair follicles. In spleen, CD4+ cells formed large clusters surrounded by mouse macrophages. In plasma, high levels of human T helper 2-type inflammatory cytokines were detectable, which activated in vitro the STAT5 pathway of murine macrophages. Despite this inflammatory pattern, human CD8+ T cells from mice with GVH reacted against the pp65 antigen in vitro. These results uncover a dynamic cross-species interaction between human memory T cells and mouse macrophages in the skin and lymphatic tissues of humanized mice.


Assuntos
Doença Enxerto-Hospedeiro/imunologia , Macrófagos/imunologia , Pele/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Antígenos CD34/análise , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Comunicação Celular/imunologia , Linhagem Celular , Citocinas/sangue , Proteínas do Citoesqueleto , Células Dendríticas/transplante , Modelos Animais de Doenças , Doença Enxerto-Hospedeiro/patologia , Transplante de Células-Tronco Hematopoéticas , Xenoenxertos , Camundongos Endogâmicos NOD , Proteínas dos Microfilamentos , Fosfoproteínas/imunologia , Pele/patologia
7.
Front Immunol ; 15: 1436676, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39324136

RESUMO

Mycobacterium tuberculosis (Mtb) infection represents a global health problem and is characterized by formation of granuloma with a necrotic center and a systemic inflammatory response. Inflammasomes have a crucial role in the host immune response towards Mtb. These intracellular multi-protein complexes are assembled in response to pathogen-associated molecular patterns (PAMPs) or danger-associated molecular patterns (DAMPs). Inflammasome platforms activate caspases, leading to the maturation of the proinflammatory cytokines interleukin (IL)-1 and 18 and the cleavage of gasdermin D (GSDMD), a pore-forming protein responsible for cytokine release and pyroptotic cell death. Recent in vitro and in vivo findings have highlighted the importance of inflammasome signaling and subsequent necrotic cell death in Mtb-infected innate immune cells. However, we are just beginning to understand how inflammasomes contribute to disease or to a protective immune response in tuberculosis (TB). A detailed molecular understanding of inflammasome-associated pathomechanisms may foster the development of novel host-directed therapeutics or vaccines with improved activity. In this mini-review, we discuss the regulatory and molecular aspects of inflammasome activation and the associated immunological consequences for Mtb pathogenesis.


Assuntos
Inflamassomos , Mycobacterium tuberculosis , Tuberculose , Humanos , Inflamassomos/imunologia , Inflamassomos/metabolismo , Mycobacterium tuberculosis/imunologia , Tuberculose/imunologia , Tuberculose/microbiologia , Animais , Inflamação/imunologia , Transdução de Sinais/imunologia , Imunidade Inata , Interações Hospedeiro-Patógeno/imunologia
8.
Nat Commun ; 15(1): 1528, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453906

RESUMO

The toll-like receptor 4 (TLR4) is a central regulator of innate immunity that primarily recognizes bacterial lipopolysaccharide cell wall constituents to trigger cytokine secretion. We identify the intramembrane protease RHBDL4 as a negative regulator of TLR4 signaling. We show that RHBDL4 triggers degradation of TLR4's trafficking factor TMED7. This counteracts TLR4 transport to the cell surface. Notably, TLR4 activation mediates transcriptional upregulation of RHBDL4 thereby inducing a negative feedback loop to reduce TLR4 trafficking to the plasma membrane. This secretory cargo tuning mechanism prevents the over-activation of TLR4-dependent signaling in an in vitro Mycobacterium tuberculosis macrophage infection model and consequently alleviates septic shock in a mouse model. A hypomorphic RHBDL4 mutation linked to Kawasaki syndrome, an ill-defined inflammatory disorder in children, further supports the pathophysiological relevance of our findings. In this work, we identify an RHBDL4-mediated axis that acts as a rheostat to prevent over-activation of the TLR4 pathway.


Assuntos
Transdução de Sinais , Receptor 4 Toll-Like , Animais , Criança , Humanos , Camundongos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Membrana Celular/metabolismo , Regulação para Baixo , Lipopolissacarídeos/metabolismo , Receptor 4 Toll-Like/metabolismo
9.
Cell Chem Biol ; 31(4): 699-711.e6, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38181799

RESUMO

Drug-resistant Mycobacterium tuberculosis (Mtb) remains a major public health concern requiring complementary approaches to standard anti-tuberculous regimens. Anti-virulence molecules or compounds that enhance the activity of antimicrobial prodrugs are promising alternatives to conventional antibiotics. Exploiting host cell-based drug discovery, we identified an oxadiazole compound (S3) that blocks the ESX-1 secretion system, a major virulence factor of Mtb. S3-treated mycobacteria showed impaired intracellular growth and a reduced ability to lyse macrophages. RNA sequencing experiments of drug-exposed bacteria revealed strong upregulation of a distinct set of genes including ethA, encoding a monooxygenase activating the anti-tuberculous prodrug ethionamide. Accordingly, we found a strong ethionamide boosting effect in S3-treated Mtb. Extensive structure-activity relationship experiments revealed that anti-virulence and ethionamide-boosting activity can be uncoupled by chemical modification of the primary hit molecule. To conclude, this series of dual-active oxadiazole compounds targets Mtb via two distinct mechanisms of action.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Sistemas de Secreção Tipo VII , Humanos , Etionamida/farmacologia , Oxidiazóis/farmacologia , Proteínas de Bactérias/genética
10.
Cells ; 13(20)2024 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-39451205

RESUMO

BACKGROUND: Humanized mice transplanted with CD34+ hematopoietic cells (HPCs) are broadly used to study human immune responses and infections in vivo and for testing therapies pre-clinically. However, until now, it was not clear whether interactions between the mouse major histocompatibility complexes (MHCs) and/or the human leukocyte antigens (HLAs) were necessary for human T-cell development and immune reactivity. METHODS: We evaluated the long-term (20-week) human hematopoiesis and human T-cell development in NOD Scid Gamma (NSG) mice lacking the expression of MHC class I and II (NSG-DKO). Triplicate experiments were performed with HPCs obtained from three donors, and humanization was confirmed in the reference strain NOD Rag Gamma (NRG). Further, we tested whether humanized NSG-DKO mice would respond to a lentiviral vector (LV) systemic delivery of HLA-A*02:01, HLA-DRB1*04:01, human GM-CSF/IFN-α, and the human cytomegalovirus gB antigen. RESULTS: Human immune reconstitution was detectable in peripheral blood from 8 to 20 weeks after the transplantation of NSG-DKO. Human single positive CD4+ and CD8+ T-cells were detectable in lymphatic tissues (thymus, bone marrow, and spleen). LV delivery harnessed the detection of lymphocyte subsets in bone marrow (αß and γδ T-cells and NK cells) and the expression of HLA-DR. Furthermore, RNA sequencing showed that LV delivery increased the expression of different human reactome pathways, such as defense responses to other organisms and viruses. CONCLUSIONS: Human T-cell development and reactivity are independent of the expression of murine MHCs in humanized mice. Therefore, humanized NSG-DKO is a promising new model for studying human immune responses, as it abrogates the xenograft mouse MHC interference.


Assuntos
Linfócitos T , Animais , Humanos , Camundongos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Reconstituição Imune , Camundongos Endogâmicos NOD , Camundongos SCID , Complexo Principal de Histocompatibilidade/genética , Transplante de Células-Tronco Hematopoéticas , Camundongos Knockout , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/imunologia , Hematopoese/genética , Transcriptoma/genética
11.
Cell Death Differ ; 31(5): 544-557, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38514848

RESUMO

The dysregulated immune response and inflammation resulting in severe COVID-19 are still incompletely understood. Having recently determined that aberrant death-ligand-induced cell death can cause lethal inflammation, we hypothesized that this process might also cause or contribute to inflammatory disease and lung failure following SARS-CoV-2 infection. To test this hypothesis, we developed a novel mouse-adapted SARS-CoV-2 model (MA20) that recapitulates key pathological features of COVID-19. Concomitantly with occurrence of cell death and inflammation, FasL expression was significantly increased on inflammatory monocytic macrophages and NK cells in the lungs of MA20-infected mice. Importantly, therapeutic FasL inhibition markedly increased survival of both, young and old MA20-infected mice coincident with substantially reduced cell death and inflammation in their lungs. Intriguingly, FasL was also increased in the bronchoalveolar lavage fluid of critically-ill COVID-19 patients. Together, these results identify FasL as a crucial host factor driving the immuno-pathology that underlies COVID-19 severity and lethality, and imply that patients with severe COVID-19 may significantly benefit from therapeutic inhibition of FasL.


Assuntos
COVID-19 , Modelos Animais de Doenças , Proteína Ligante Fas , SARS-CoV-2 , Animais , Camundongos , Líquido da Lavagem Broncoalveolar , COVID-19/patologia , COVID-19/imunologia , COVID-19/metabolismo , COVID-19/virologia , COVID-19/mortalidade , Proteína Ligante Fas/metabolismo , Inflamação/patologia , Inflamação/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Pulmão/patologia , Pulmão/virologia , Pulmão/metabolismo , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos Endogâmicos C57BL
12.
Cells ; 13(1)2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-38201224

RESUMO

Antiviral neutralizing antibodies (nAbs) are commonly derived from B cells developed in immunized or infected animals and humans. Fully human antibodies are preferred for clinical use as they are potentially less immunogenic. However, the function of B cells varies depending on their homing pattern and an additional hurdle for antibody discovery in humans is the source of human tissues with an immunological microenvironment. Here, we show an efficient method to pharm human antibodies using immortalized B cells recovered from Nod.Rag.Gamma (NRG) mice reconstituting the human immune system (HIS). Humanized HIS mice were immunized either with autologous engineered dendritic cells expressing the human cytomegalovirus gB envelope protein (HCMV-gB) or with Epstein-Barr virus-like particles (EB-VLP). Human B cells recovered from spleen of HIS mice were efficiently immortalized with EBV in vitro. We show that these immortalized B cells secreted human IgGs with neutralization capacities against prototypic HCMV-gB and EBV-gp350. Taken together, we show that HIS mice can be successfully used for the generation and pharming fully human IgGs. This technology can be further explored to generate antibodies against emerging infections for diagnostic or therapeutic purposes.


Assuntos
Vacinas Anticâncer , Infecções por Vírus Epstein-Barr , Humanos , Animais , Camundongos , Baço , Herpesvirus Humano 4 , Anticorpos Antivirais , Imunoglobulina G , Citomegalovirus
13.
J Mol Cell Biol ; 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891014

RESUMO

The novel coronavirus pandemic, first reported in December 2019, was caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 infection leads to a strong immune response and activation of antigen-presenting cells, which can elicit acute respiratory distress syndrome (ARDS) characterized by the rapid onset of widespread inflammation, the so-called cytokine storm. In response to viral infections, monocytes are recruited into the lung and subsequently differentiate into dendritic cells (DCs). DCs are critical players in the development of the acute lung inflammation that causes ARDS. Here we focus on the interaction of a specific SARS-CoV-2 open reading frame protein, ORF8, with DCs. We show that ORF8 binds to DCs, causes a pre-maturation of differentiating DCs, and induces the secretion of multiple proinflammatory cytokines by these cells. In addition, we identified DC-SIGN as a possible interaction partner of ORF8 on DCs. Blockade of ORF8 leads to reduced production of IL-1ß, IL-6, IL-12p70, TNF-α, MCP-1 (also named CCL2), and IL-10 by DCs. Therefore, a neutralizing antibody blocking the ORF8-mediated cytokine and chemokine response could be an improved therapeutical strategy against severe SARS-CoV-2.

14.
Front Med (Lausanne) ; 10: 1129288, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37168268

RESUMO

Background: Symptoms lasting longer than 12 weeks after severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) infection are called post-coronavirus disease (COVID) syndrome (PCS). The identification of new biomarkers that predict the occurrence or course of PCS in terms of a post-viral syndrome is vital. T-cell dysfunction, cytokine imbalance, and impaired autoimmunity have been reported in PCS. Nevertheless, there is still a lack of conclusive information on the underlying mechanisms due to, among other things, a lack of controlled study designs. Methods: Here, we conducted a prospective, controlled study to characterize the humoral and cellular immune response in unvaccinated patients with and without PCS following SARS-CoV-2 infection over 7 months and unexposed donors. Results: Patients with PCS showed as early as 6 weeks and 7 months after symptom onset significantly increased frequencies of SARS-CoV-2-specific CD4+ and CD8+ T-cells secreting IFNγ, TNF, and expressing CD40L, as well as plasmacytoid dendritic cells (pDC) with an activated phenotype. Remarkably, the immunosuppressive counterparts type 1 regulatory T-cells (TR1: CD49b/LAG-3+) and IL-4 were more abundant in PCS+. Conclusion: This work describes immunological alterations between inflammation and immunosuppression in COVID-19 convalescents with and without PCS, which may provide potential directions for future epidemiological investigations and targeted treatments.

15.
EMBO Mol Med ; 14(8): e15888, 2022 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-35785445

RESUMO

Durable cell-mediated immune responses require efficient innate immune signaling and the release of pro-inflammatory cytokines. How precisely mRNA vaccines trigger innate immune cells for shaping antigen specific adaptive immunity remains unknown. Here, we show that SARS-CoV-2 mRNA vaccination primes human monocyte-derived macrophages for activation of the NLRP3 inflammasome. Spike protein exposed macrophages undergo NLRP3-driven pyroptotic cell death and subsequently secrete mature interleukin-1ß. These effects depend on activation of spleen tyrosine kinase (SYK) coupled to C-type lectin receptors. Using autologous cocultures, we show that SYK and NLRP3 orchestrate macrophage-driven activation of effector memory T cells. Furthermore, vaccination-induced macrophage priming can be enhanced with repetitive antigen exposure providing a rationale for prime-boost concepts to augment innate immune signaling in SARS-CoV-2 vaccination. Collectively, these findings identify SYK as a regulatory node capable of differentiating between primed and unprimed macrophages, which modulate spike protein-specific T cell responses.


Assuntos
COVID-19 , Proteína 3 que Contém Domínio de Pirina da Família NLR , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Imunidade Inata , Inflamassomos/metabolismo , Interleucina-1beta , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Tirosina Quinases/metabolismo , RNA Mensageiro/genética , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética , Quinase Syk , Vacinação
16.
EMBO Mol Med ; 13(1): e13105, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33015938

RESUMO

The ongoing SARS-CoV-2 pandemic stresses the need for effective antiviral drugs that can quickly be applied in order to reduce morbidity, mortality, and ideally viral transmission. By repurposing of broadly active antiviral drugs and compounds that are known to inhibit viral replication of related viruses, several advances could be made in the development of treatment strategies against COVID-19. The nucleoside analog remdesivir, which is known for its potent in vitro activity against Ebolavirus and other RNA viruses, was recently shown to reduce the time to recovery in patients with severe COVID-19. It is to date the only approved antiviral for treating COVID-19. Here, we provide a mechanism and evidence-based comparative review of remdesivir and other repurposed drugs with proven in vitro activity against SARS-CoV-2.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Antivirais/uso terapêutico , Tratamento Farmacológico da COVID-19 , Reposicionamento de Medicamentos , SARS-CoV-2/efeitos dos fármacos , Monofosfato de Adenosina/farmacologia , Monofosfato de Adenosina/uso terapêutico , Alanina/farmacologia , Alanina/uso terapêutico , Amidas/farmacologia , Amidas/uso terapêutico , Antivirais/farmacologia , Benzamidinas , Reposicionamento de Medicamentos/métodos , Ésteres/farmacologia , Ésteres/uso terapêutico , Guanidinas/farmacologia , Guanidinas/uso terapêutico , Guanina/farmacologia , Guanina/uso terapêutico , Humanos , Indóis/farmacologia , Indóis/uso terapêutico , Lopinavir/farmacologia , Lopinavir/uso terapêutico , Inibidores de Proteases/farmacologia , Inibidores de Proteases/uso terapêutico , Pirazinas/farmacologia , Pirazinas/uso terapêutico , Ribavirina/farmacologia , Ribavirina/uso terapêutico , Ritonavir/farmacologia , Ritonavir/uso terapêutico , SARS-CoV-2/fisiologia , Internalização do Vírus/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos
17.
Viruses ; 13(10)2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34696506

RESUMO

Infections with viral pathogens are widespread and can cause a variety of different diseases. In-depth knowledge about viral triggers initiating an immune response is necessary to decipher viral pathogenesis. Inflammasomes, as part of the innate immune system, can be activated by viral pathogens. However, viral structural components responsible for inflammasome activation remain largely unknown. Here we analyzed glycoproteins derived from SARS-CoV-1/2, HCMV and HCV, required for viral entry and fusion, as potential triggers of NLRP3 inflammasome activation and pyroptosis in THP-1 macrophages. All tested glycoproteins were able to potently induce NLRP3 inflammasome activation, indicated by ASC-SPECK formation and secretion of cleaved IL-1ß. Lytic cell death via gasdermin D (GSDMD), pore formation, and pyroptosis are required for IL-1ß release. As a hallmark of pyroptosis, we were able to detect cleavage of GSDMD and, correspondingly, cell death in THP-1 macrophages. CRISPR-Cas9 knockout of NLRP3 and GSDMD in THP-1 macrophages confirmed and strongly support the evidence that viral glycoproteins can act as innate immunity triggers. With our study, we decipher key mechanisms of viral pathogenesis by showing that viral glycoproteins potently induce innate immune responses. These insights could be beneficial in vaccine development and provide new impulses for the investigation of vaccine-induced innate immunity.


Assuntos
Imunidade Inata/imunologia , Inflamassomos/imunologia , Macrófagos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Proteínas do Envelope Viral/imunologia , Proteínas Virais de Fusão/imunologia , Linhagem Celular Tumoral , Citomegalovirus/imunologia , Hepacivirus/imunologia , Humanos , Interleucina-1beta/biossíntese , Interleucina-1beta/imunologia , Piroptose/imunologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , SARS-CoV-2/imunologia , Células THP-1
18.
Cell Death Discov ; 7(1): 327, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34718331

RESUMO

Necrotic cell death represents a major pathogenic mechanism of Mycobacterium tuberculosis (Mtb) infection. It is increasingly evident that Mtb induces several types of regulated necrosis but how these are interconnected and linked to the release of pro-inflammatory cytokines remains unknown. Exploiting a clinical cohort of tuberculosis patients, we show here that the number and size of necrotic lesions correlates with IL-1ß plasma levels as a strong indicator of inflammasome activation. Our mechanistic studies reveal that Mtb triggers mitochondrial permeability transition (mPT) and subsequently extensive macrophage necrosis, which requires activation of the NLRP3 inflammasome. NLRP3-driven mitochondrial damage is dependent on proteolytic activation of the pore-forming effector protein gasdermin D (GSDMD), which links two distinct cell death machineries. Intriguingly, GSDMD, but not the membranolytic mycobacterial ESX-1 secretion system, is dispensable for IL-1ß secretion from Mtb-infected macrophages. Thus, our study dissects a novel mechanism of pathogen-induced regulated necrosis by identifying mitochondria as central regulatory hubs capable of delineating cytokine secretion and lytic cell death.

19.
Biomedicines ; 9(8)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34440166

RESUMO

Humanized mouse models generated with human hematopoietic stem cells (HSCs) and reconstituting the human immune system (HIS-mice) are invigorating preclinical testing of vaccines and immunotherapies. We have recently shown that human engineered dendritic cells boosted bonafide human T and B cell maturation and antigen-specific responses in HIS-mice. Here, we evaluated a cell-free system based on in vivo co-delivery of lentiviral vectors (LVs) for expression of a human leukocyte antigen (HLA-DRA*01/ HLA-DRB1*0401 functional complex, "DR4"), and a LV vaccine expressing human cytokines (GM-CSF and IFN-α) and a human cytomegalovirus gB antigen (HCMV-gB). Humanized NOD/Rag1null/IL2Rγnull (NRG) mice injected by i.v. with LV-DR4/fLuc showed long-lasting (up to 20 weeks) vector distribution and expression in the spleen and liver. In vivo administration of the LV vaccine after LV-DR4/fLuc delivery boosted the cellularity of lymph nodes, promoted maturation of terminal effector CD4+ T cells, and promoted significantly higher development of IgG+ and IgA+ B cells. This modular lentigenic system opens several perspectives for basic human immunology research and preclinical utilization of LVs to deliver HLAs into HIS-mice.

20.
EMBO Mol Med ; 13(8): e14150, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34133077

RESUMO

Innate immunity triggers responsible for viral control or hyperinflammation in COVID-19 are largely unknown. Here we show that the SARS-CoV-2 spike protein (S-protein) primes inflammasome formation and release of mature interleukin-1ß (IL-1ß) in macrophages derived from COVID-19 patients but not in macrophages from healthy SARS-CoV-2 naïve individuals. Furthermore, longitudinal analyses reveal robust S-protein-driven inflammasome activation in macrophages isolated from convalescent COVID-19 patients, which correlates with distinct epigenetic and gene expression signatures suggesting innate immune memory after recovery from COVID-19. Importantly, we show that S-protein-driven IL-1ß secretion from patient-derived macrophages requires non-specific monocyte pre-activation in vivo to trigger NLRP3-inflammasome signaling. Our findings reveal that SARS-CoV-2 infection causes profound and long-lived reprogramming of macrophages resulting in augmented immunogenicity of the SARS-CoV-2 S-protein, a major vaccine antigen and potent driver of adaptive and innate immune signaling.


Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Humanos , Imunidade Inata , Inflamassomos , Interleucina-1beta , Macrófagos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , SARS-CoV-2
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