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1.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204438

RESUMO

Hepatitis C virus (HCV) is associated with various liver diseases. Chronic HCV infection is characterized by an abnormal host immune response. Therefore, it is speculated that to suppress HCV, a well-regulated host immune response is necessary. 2-O-methylhonokiol was identified by the screening of anti-HCV compounds using Renilla luciferase assay in Huh 7.5/Con 1 genotype 1b replicon cells. Here, we investigated the mechanism by which 2-O-methylhonokiol treatment inhibits HCV replication using real-time PCR. Our data shows that treatment with 2-O-methylhonokiol activated innate immune responses via nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) pathway. Additionally, the immunoprecipitation result shows that treatment with 2-O-methylhonokiol augmented tumor necrosis factor receptor (TNFR)-associated factor 6 (TRAF6) by preventing p62 from binding to TRAF6, resulting in reduced autophagy caused by HCV. Finally, we reproduced our data with the conditioned media from 2-O-methylhonokiol-treated cells. These findings strongly suggest that 2-O-methylhonokiol enhances the host immune response and suppresses HCV replication via TRAF6-mediated NF-kB activation.


Assuntos
Hepacivirus/fisiologia , Hepatite C/metabolismo , Hepatite C/virologia , Interações Hospedeiro-Patógeno , NF-kappa B/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Replicação Viral , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linhagem Celular , Células Cultivadas , Hepatite C/imunologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata , Modelos Biológicos , Estrutura Molecular
2.
Nat Cell Biol ; 23(6): 620-630, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34108657

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection often causes severe complications and even death. However, asymptomatic infection has also been reported, highlighting the difference in immune responses among individuals. Here we performed single-cell chromatin accessibility and T cell-receptor analyses of peripheral blood mononuclear cells collected from individuals convalescing from COVID-19 and healthy donors. Chromatin remodelling was observed in both innate and adaptive immune cells in the individuals convalescing from COVID-19. Compared with healthy donors, recovered individuals contained abundant TBET-enriched CD16+ and IRF1-enriched CD14+ monocytes with sequential trained and activated epigenomic states. The B-cell lineage in recovered individuals exhibited an accelerated developmental programme from immature B cells to antibody-producing plasma cells. Finally, an integrated analysis of single-cell T cell-receptor clonality with the chromatin accessibility landscape revealed the expansion of putative SARS-CoV-2-specific CD8+ T cells with epigenomic profiles that promote the differentiation of effector or memory cells. Overall, our data suggest that immune cells of individuals convalescing from COVID-19 exhibit global remodelling of the chromatin accessibility landscape, indicative of the establishment of immunological memory.


Assuntos
COVID-19/genética , Epigênese Genética , Epigenômica , Genes Codificadores dos Receptores de Linfócitos T , Memória Imunológica , Subpopulações de Linfócitos/imunologia , Monócitos/imunologia , SARS-CoV-2/imunologia , Análise de Célula Única , Imunidade Adaptativa , Adolescente , Adulto , Idoso , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , COVID-19/imunologia , COVID-19/metabolismo , COVID-19/virologia , Estudos de Casos e Controles , Diferenciação Celular , Montagem e Desmontagem da Cromatina , Feminino , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Subpopulações de Linfócitos/metabolismo , Subpopulações de Linfócitos/virologia , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Monócitos/virologia , SARS-CoV-2/patogenicidade , Adulto Jovem
3.
Viruses ; 13(6)2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34064104

RESUMO

Patients with coronavirus disease 2019 (COVID-19) predominantly have a respiratory tract infection with various symptoms and high mortality is associated with respiratory failure second to severe disease. The risk factors leading to severe disease remain unclear. Here, we reanalyzed a published single-cell RNA-Seq (scRNA-Seq) dataset and found that bronchoalveolar lavage fluid (BALF) of patients with severe disease compared to those with mild disease contained decreased TH17-type cells, decreased IFNA1-expressing cells with lower expression of toll-like receptor 7 (TLR7) and TLR8, increased IgA-expressing B cells, and increased hyperactive epithelial cells (and/or macrophages) expressing matrix metalloproteinases (MMPs), hyaluronan synthase 2 (HAS2), and plasminogen activator inhibitor-1 (PAI-1), which may together contribute to the pulmonary pathology in severe COVID-19. We propose IFN-I (and TLR7/TLR8) and PAI-1 as potential biomarkers to predict the susceptibility to severe COVID-19.


Assuntos
COVID-19/patologia , Pulmão/patologia , Linfócitos B/metabolismo , Linfócitos B/patologia , Biomarcadores/metabolismo , Líquido da Lavagem Broncoalveolar/imunologia , COVID-19/imunologia , COVID-19/metabolismo , Bases de Dados Genéticas , Humanos , Hialuronan Sintases/metabolismo , Imunoglobulina A/metabolismo , Interferon-alfa/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Metaloproteinases da Matriz/metabolismo , Mucina-1/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , RNA-Seq , SARS-CoV-2 , Células Th17/metabolismo , Células Th17/patologia
4.
Viruses ; 13(6)2021 05 21.
Artigo em Inglês | MEDLINE | ID: covidwho-1244141

RESUMO

Patients with coronavirus disease 2019 (COVID-19) predominantly have a respiratory tract infection with various symptoms and high mortality is associated with respiratory failure second to severe disease. The risk factors leading to severe disease remain unclear. Here, we reanalyzed a published single-cell RNA-Seq (scRNA-Seq) dataset and found that bronchoalveolar lavage fluid (BALF) of patients with severe disease compared to those with mild disease contained decreased TH17-type cells, decreased IFNA1-expressing cells with lower expression of toll-like receptor 7 (TLR7) and TLR8, increased IgA-expressing B cells, and increased hyperactive epithelial cells (and/or macrophages) expressing matrix metalloproteinases (MMPs), hyaluronan synthase 2 (HAS2), and plasminogen activator inhibitor-1 (PAI-1), which may together contribute to the pulmonary pathology in severe COVID-19. We propose IFN-I (and TLR7/TLR8) and PAI-1 as potential biomarkers to predict the susceptibility to severe COVID-19.


Assuntos
COVID-19/patologia , Pulmão/patologia , Linfócitos B/metabolismo , Linfócitos B/patologia , Biomarcadores/metabolismo , Líquido da Lavagem Broncoalveolar/imunologia , COVID-19/imunologia , COVID-19/metabolismo , Bases de Dados Genéticas , Humanos , Hialuronan Sintases/metabolismo , Imunoglobulina A/metabolismo , Interferon-alfa/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Metaloproteinases da Matriz/metabolismo , Mucina-1/metabolismo , Inibidor 1 de Ativador de Plasminogênio/metabolismo , RNA-Seq , SARS-CoV-2 , Células Th17/metabolismo , Células Th17/patologia
5.
Nat Cell Biol ; 23(6): 620-630, 2021 06.
Artigo em Inglês | MEDLINE | ID: covidwho-1263492

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection often causes severe complications and even death. However, asymptomatic infection has also been reported, highlighting the difference in immune responses among individuals. Here we performed single-cell chromatin accessibility and T cell-receptor analyses of peripheral blood mononuclear cells collected from individuals convalescing from COVID-19 and healthy donors. Chromatin remodelling was observed in both innate and adaptive immune cells in the individuals convalescing from COVID-19. Compared with healthy donors, recovered individuals contained abundant TBET-enriched CD16+ and IRF1-enriched CD14+ monocytes with sequential trained and activated epigenomic states. The B-cell lineage in recovered individuals exhibited an accelerated developmental programme from immature B cells to antibody-producing plasma cells. Finally, an integrated analysis of single-cell T cell-receptor clonality with the chromatin accessibility landscape revealed the expansion of putative SARS-CoV-2-specific CD8+ T cells with epigenomic profiles that promote the differentiation of effector or memory cells. Overall, our data suggest that immune cells of individuals convalescing from COVID-19 exhibit global remodelling of the chromatin accessibility landscape, indicative of the establishment of immunological memory.


Assuntos
COVID-19/genética , Epigênese Genética , Epigenômica , Genes Codificadores dos Receptores de Linfócitos T , Memória Imunológica , Subpopulações de Linfócitos/imunologia , Monócitos/imunologia , SARS-CoV-2/imunologia , Análise de Célula Única , Imunidade Adaptativa , Adolescente , Adulto , Idoso , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/virologia , COVID-19/imunologia , COVID-19/metabolismo , COVID-19/virologia , Estudos de Casos e Controles , Diferenciação Celular , Montagem e Desmontagem da Cromatina , Feminino , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Subpopulações de Linfócitos/metabolismo , Subpopulações de Linfócitos/virologia , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Monócitos/virologia , SARS-CoV-2/patogenicidade , Adulto Jovem
6.
Nat Commun ; 12(1): 3501, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: covidwho-1263489

RESUMO

The characteristics of COVID-19 patients with persistent SARS-CoV-2 infection are not yet well described. Here, we compare the clinical and molecular features of patients with long duration of viral shedding (LDs) with those from patients with short duration patients (SDs), and healthy donors (HDs). We find that several cytokines and chemokines, such as interleukin (IL)-2, tumor necrosis factor (TNF) and lymphotoxin α (LT-α) are present at lower levels in LDs than SDs. Single-cell RNA sequencing shows that natural killer (NK) cells and CD14+ monocytes are reduced, while regulatory T cells are increased in LDs; moreover, T and NK cells in LDs are less activated than in SDs. Importantly, most cells in LDs show reduced expression of ribosomal protein (RP) genes and related pathways, with this inversed correlation between RP levels and infection duration further validated in 103 independent patients. Our results thus indicate that immunosuppression and low RP expression may be related to the persistence of the viral infection in COVID-19 patients.


Assuntos
COVID-19/imunologia , SARS-CoV-2/patogenicidade , Linfócitos B/metabolismo , Linfócitos B/patologia , COVID-19/virologia , Citocinas/sangue , Perfilação da Expressão Gênica , Humanos , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/patologia , Leucócitos Mononucleares/patologia , Ativação Linfocitária/genética , Subpopulações de Linfócitos/metabolismo , Subpopulações de Linfócitos/patologia , Proteínas Ribossômicas/genética , SARS-CoV-2/isolamento & purificação , Transdução de Sinais/genética , Linfócitos T/metabolismo , Linfócitos T/patologia , Eliminação de Partículas Virais
7.
Int J Mol Sci ; 22(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072618

RESUMO

Adaptive immunity relies on the V(D)J DNA recombination of immunoglobulin (Ig) and T cell receptor (TCR) genes, which enables the recognition of highly diverse antigens and the elicitation of antigen-specific immune responses. This process is mediated by recombination-activating gene (Rag) 1 and Rag2 (Rag1/2), whose expression is strictly controlled in a cell type-specific manner; the expression of Rag1/2 genes represents a hallmark of lymphoid lineage commitment. Although Rag genes are known to be evolutionally conserved among jawed vertebrates, how Rag genes are regulated by lineage-specific transcription factors (TFs) and how their regulatory system evolved among vertebrates have not been fully elucidated. Here, we reviewed the current body of knowledge concerning the cis-regulatory elements (CREs) of Rag genes and the evolution of the basic helix-loop-helix TF E protein regulating Rag gene CREs, as well as the evolution of the antagonist of this protein, the Id protein. This may help to understand how the adaptive immune system develops along with the evolution of responsible TFs and enhancers.


Assuntos
Imunidade Adaptativa/genética , Elementos Facilitadores Genéticos , Evolução Molecular , Proteínas de Homeodomínio/genética , Fatores de Transcrição/genética , Animais , Linfócitos B/citologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Regulação da Expressão Gênica , Humanos , Sequências Reguladoras de Ácido Nucleico , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Fatores de Transcrição/metabolismo , Recombinação V(D)J
8.
Nat Commun ; 12(1): 3501, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108465

RESUMO

The characteristics of COVID-19 patients with persistent SARS-CoV-2 infection are not yet well described. Here, we compare the clinical and molecular features of patients with long duration of viral shedding (LDs) with those from patients with short duration patients (SDs), and healthy donors (HDs). We find that several cytokines and chemokines, such as interleukin (IL)-2, tumor necrosis factor (TNF) and lymphotoxin α (LT-α) are present at lower levels in LDs than SDs. Single-cell RNA sequencing shows that natural killer (NK) cells and CD14+ monocytes are reduced, while regulatory T cells are increased in LDs; moreover, T and NK cells in LDs are less activated than in SDs. Importantly, most cells in LDs show reduced expression of ribosomal protein (RP) genes and related pathways, with this inversed correlation between RP levels and infection duration further validated in 103 independent patients. Our results thus indicate that immunosuppression and low RP expression may be related to the persistence of the viral infection in COVID-19 patients.


Assuntos
COVID-19/imunologia , SARS-CoV-2/patogenicidade , Linfócitos B/metabolismo , Linfócitos B/patologia , COVID-19/virologia , Citocinas/sangue , Perfilação da Expressão Gênica , Humanos , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/patologia , Leucócitos Mononucleares/patologia , Ativação Linfocitária/genética , Subpopulações de Linfócitos/metabolismo , Subpopulações de Linfócitos/patologia , Proteínas Ribossômicas/genética , SARS-CoV-2/isolamento & purificação , Transdução de Sinais/genética , Linfócitos T/metabolismo , Linfócitos T/patologia , Eliminação de Partículas Virais
9.
Front Immunol ; 12: 620437, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33936036

RESUMO

T Follicular helper (Tfh) cells promote germinal center (GC) B cell responses to develop effective humoral immunity against pathogens. However, dysregulated Tfh cells can also trigger autoantibody production and the development of autoimmune diseases. We report here that Tsc1, a regulator for mTOR signaling, plays differential roles in Tfh cell/GC B cell responses in the steady state and in immune responses to antigen immunization. In the steady state, Tsc1 in T cells intrinsically suppresses spontaneous GC-Tfh cell differentiation and subsequent GC-B cell formation and autoantibody production. In immune responses to antigen immunization, Tsc1 in T cells is required for efficient GC-Tfh cell expansion, GC-B cell induction, and antigen-specific antibody responses, at least in part via promoting GC-Tfh cell mitochondrial integrity and survival. Interestingly, in mixed bone marrow chimeric mice reconstituted with both wild-type and T cell-specific Tsc1-deficient bone marrow cells, Tsc1 deficiency leads to enhanced GC-Tfh cell differentiation of wild-type CD4 T cells and increased accumulation of wild-type T regulatory cells and T follicular regulatory cells. Such bystander GC-Tfh cell differentiation suggests a potential mechanism that could trigger self-reactive GC-Tfh cell/GC responses and autoimmunity via neighboring GC-Tfh cells.


Assuntos
Autoimunidade , Diferenciação Celular/imunologia , Imunomodulação/genética , Células T Auxiliares Foliculares/imunologia , Células T Auxiliares Foliculares/metabolismo , Proteína 1 do Complexo Esclerose Tuberosa/genética , Animais , Formação de Anticorpos/genética , Formação de Anticorpos/imunologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Autoimunidade/genética , Autoimunidade/imunologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Diferenciação Celular/genética , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Proteína 1 do Complexo Esclerose Tuberosa/metabolismo
10.
Front Immunol ; 12: 639329, 2021.
Artigo em Inglês | MEDLINE | ID: covidwho-1219713

RESUMO

Background: Infection with the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a wide range of symptoms including gastrointestinal manifestations, and intestinal epithelial cells are a target of the virus. However, it is unknown how the intestinal immune system contributes to systemic immune responses in coronavirus disease 2019 (COVID-19). Methods: We characterized peripheral blood lymphocytes from patients with active COVID-19 and convalescent patients as well as healthy controls by flow cytometry. Results: The frequency and absolute number of circulating memory T and B cells expressing the gut homing integrin α4ß7 integrin was reduced during COVID-19, whether gastrointestinal symptoms were present or not. While total IgA-expressing B cells were increased, gut-imprinted B cells with IgA expression were stable. Conclusion: COVID-19 is associated with a decrease in circulating adaptive immune cells expressing the key gut homing marker α4ß7 suggesting that these cells are preferentially recruited to extra-intestinal tissues independently of α4ß7 or that the systemic immune response against SARS-CoV-2 is at least numerically dominated by extraintestinal, particularly pulmonary, immune cell priming.


Assuntos
Linfócitos B/metabolismo , COVID-19/imunologia , Integrina alfa4/metabolismo , Integrinas/metabolismo , SARS-CoV-2/imunologia , Linfócitos T/metabolismo , Adulto , Linfócitos B/imunologia , Biomarcadores/análise , COVID-19/patologia , Feminino , Humanos , Memória Imunológica/imunologia , Mucosa Intestinal/citologia , Mucosa Intestinal/imunologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia
11.
Immunity ; 54(6): 1290-1303.e7, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: covidwho-1237724

RESUMO

Dissecting the evolution of memory B cells (MBCs) against SARS-CoV-2 is critical for understanding antibody recall upon secondary exposure. Here, we used single-cell sequencing to profile SARS-CoV-2-reactive B cells in 38 COVID-19 patients. Using oligo-tagged antigen baits, we isolated B cells specific to the SARS-CoV-2 spike, nucleoprotein (NP), open reading frame 8 (ORF8), and endemic human coronavirus (HCoV) spike proteins. SARS-CoV-2 spike-specific cells were enriched in the memory compartment of acutely infected and convalescent patients several months post symptom onset. With severe acute infection, substantial populations of endemic HCoV-reactive antibody-secreting cells were identified and possessed highly mutated variable genes, signifying preexisting immunity. Finally, MBCs exhibited pronounced maturation to NP and ORF8 over time, especially in older patients. Monoclonal antibodies against these targets were non-neutralizing and non-protective in vivo. These findings reveal antibody adaptation to non-neutralizing intracellular antigens during infection, emphasizing the importance of vaccination for inducing neutralizing spike-specific MBCs.


Assuntos
Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Linfócitos B/imunologia , COVID-19/imunologia , Interações Hospedeiro-Patógeno/imunologia , Epitopos Imunodominantes/imunologia , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/imunologia , Formação de Anticorpos/genética , Linfócitos B/metabolismo , Biologia Computacional/métodos , Reações Cruzadas/imunologia , Mapeamento de Epitopos , Feminino , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno/genética , Humanos , Epitopos Imunodominantes/genética , Memória Imunológica , Masculino , Testes de Neutralização , Análise de Célula Única/métodos , Glicoproteína da Espícula de Coronavírus/imunologia , Transcriptoma
12.
Front Immunol ; 12: 665522, 2021.
Artigo em Inglês | MEDLINE | ID: covidwho-1211818

RESUMO

COVID-19 is characterized by a severe pulmonary disease due to severe acute respiratory syndrome (SARS)-CoV-2 infection. For clinicians involved in the management of patients with chronic autoimmune diseases the risk linked to the conditions itself and to drug-induced immunosuppression during the COVID-19 pandemic is a major topic. Pemphigus is a rare autoimmune blistering disease (AIBD) of the skin and mucous membranes caused by autoantibodies to desmosomal components, desmoglein 1 and 3. Among immunosuppressant therapies, rituximab (RTX) is considered a highly effective treatment with a favorable safety profile, but it induces a prolonged B-cell depletion that can lead to higher susceptibility to infections. For this reason, concerns about its use during the pandemic have been raised. We describe a case of a pemphigus patient in which RTX-induced B cell depletion led to the severe inflammatory phase, whereas corticosteroid treatment allowed a favorable outcome.


Assuntos
Corticosteroides/uso terapêutico , Linfócitos B/imunologia , COVID-19/tratamento farmacológico , Pênfigo/imunologia , Rituximab/efeitos adversos , Corticosteroides/efeitos adversos , Linfócitos B/metabolismo , COVID-19/complicações , COVID-19/fisiopatologia , Feminino , Febre , Humanos , Imunoglobulina G/imunologia , Inflamação/tratamento farmacológico , Pessoa de Meia-Idade , Oxigenoterapia , Pênfigo/complicações , Pênfigo/tratamento farmacológico , Rituximab/uso terapêutico
13.
Cell ; 184(12): 3205-3221.e24, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: covidwho-1201121

RESUMO

Monoclonal antibodies (mAbs) are a focus in vaccine and therapeutic design to counteract severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants. Here, we combined B cell sorting with single-cell VDJ and RNA sequencing (RNA-seq) and mAb structures to characterize B cell responses against SARS-CoV-2. We show that the SARS-CoV-2-specific B cell repertoire consists of transcriptionally distinct B cell populations with cells producing potently neutralizing antibodies (nAbs) localized in two clusters that resemble memory and activated B cells. Cryo-electron microscopy structures of selected nAbs from these two clusters complexed with SARS-CoV-2 spike trimers show recognition of various receptor-binding domain (RBD) epitopes. One of these mAbs, BG10-19, locks the spike trimer in a closed conformation to potently neutralize SARS-CoV-2, the recently arising mutants B.1.1.7 and B.1.351, and SARS-CoV and cross-reacts with heterologous RBDs. Together, our results characterize transcriptional differences among SARS-CoV-2-specific B cells and uncover cross-neutralizing Ab targets that will inform immunogen and therapeutic design against coronaviruses.


Assuntos
Anticorpos Neutralizantes/imunologia , Linfócitos B/metabolismo , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/química , Anticorpos Antivirais/sangue , Anticorpos Antivirais/química , Anticorpos Antivirais/imunologia , Complexo Antígeno-Anticorpo/química , Complexo Antígeno-Anticorpo/metabolismo , Reações Antígeno-Anticorpo , Linfócitos B/citologia , Linfócitos B/virologia , COVID-19/patologia , COVID-19/virologia , Microscopia Crioeletrônica , Cristalografia por Raios X , Perfilação da Expressão Gênica , Humanos , Imunoglobulina A/imunologia , Região Variável de Imunoglobulina/química , Região Variável de Imunoglobulina/genética , Domínios Proteicos/imunologia , Multimerização Proteica , Estrutura Quaternária de Proteína , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/metabolismo , Análise de Sequência de RNA , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
14.
Immunity ; 54(6): 1290-1303.e7, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34022127

RESUMO

Dissecting the evolution of memory B cells (MBCs) against SARS-CoV-2 is critical for understanding antibody recall upon secondary exposure. Here, we used single-cell sequencing to profile SARS-CoV-2-reactive B cells in 38 COVID-19 patients. Using oligo-tagged antigen baits, we isolated B cells specific to the SARS-CoV-2 spike, nucleoprotein (NP), open reading frame 8 (ORF8), and endemic human coronavirus (HCoV) spike proteins. SARS-CoV-2 spike-specific cells were enriched in the memory compartment of acutely infected and convalescent patients several months post symptom onset. With severe acute infection, substantial populations of endemic HCoV-reactive antibody-secreting cells were identified and possessed highly mutated variable genes, signifying preexisting immunity. Finally, MBCs exhibited pronounced maturation to NP and ORF8 over time, especially in older patients. Monoclonal antibodies against these targets were non-neutralizing and non-protective in vivo. These findings reveal antibody adaptation to non-neutralizing intracellular antigens during infection, emphasizing the importance of vaccination for inducing neutralizing spike-specific MBCs.


Assuntos
Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Linfócitos B/imunologia , COVID-19/imunologia , Interações Hospedeiro-Patógeno/imunologia , Epitopos Imunodominantes/imunologia , SARS-CoV-2/imunologia , Anticorpos Neutralizantes/imunologia , Formação de Anticorpos/genética , Linfócitos B/metabolismo , Biologia Computacional/métodos , Reações Cruzadas/imunologia , Mapeamento de Epitopos , Feminino , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno/genética , Humanos , Epitopos Imunodominantes/genética , Memória Imunológica , Masculino , Testes de Neutralização , Análise de Célula Única/métodos , Glicoproteína da Espícula de Coronavírus/imunologia , Transcriptoma
15.
Biochemistry (Mosc) ; 86(5): 568-576, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33993864

RESUMO

Recent studies have predominantly focused on the role of B cells in metabolic diseases, yet the function of B cells in adipose homeostasis remains unclear. Pax transactivation domain-interacting protein (PTIP), a licensing factor for humoral immunity, is necessary for B cell development and activation. Here, using mice that lack PTIP in B cells (PTIP-/- mice), we explored the role of B cells in adipose homeostasis under physiological conditions. Fat deposition in 8-week-old mice was measured by micro-CT, and PTIP-/- mice presented a marked decrease in the deposition of subcutaneous adipose tissue (SAT). Untargeted lipidomics revealed that the triglyceride composition in SAT was altered in PTIP-/- mice. In addition, there was no difference in the number of adipocyte progenitor cells in the SAT of wild-type (WT) and PTIP-/- mice as measured by flow cytometry. To study the effects of steady-state IgM and IgG antibody levels on fat deposition, PTIP-/- mice were injected intraperitoneally with serum from WT mice once every 3-4 days for 4 weeks. The iSAT mass of the recipient mice showed no significant increase in comparison to the controls after 4 weeks of injections. Our findings reveal that PTIP plays an essential role in regulating subcutaneous adipocyte size, triglyceride composition, and fat deposition under physiological conditions by controlling B cells. The decreased subcutaneous fat deposition in PTIP-/- mice does not appear to be related to the number of adipocyte progenitor cells. The steady-state levels of IgM and IgG antibodies in vivo are not associated with the subcutaneous fat deposition.


Assuntos
Linfócitos B/metabolismo , Proteínas de Ligação a DNA/genética , Gordura Subcutânea/metabolismo , Animais , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Masculino , Camundongos , Células-Tronco , Gordura Subcutânea/fisiologia
16.
Front Immunol ; 12: 665522, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33936104

RESUMO

COVID-19 is characterized by a severe pulmonary disease due to severe acute respiratory syndrome (SARS)-CoV-2 infection. For clinicians involved in the management of patients with chronic autoimmune diseases the risk linked to the conditions itself and to drug-induced immunosuppression during the COVID-19 pandemic is a major topic. Pemphigus is a rare autoimmune blistering disease (AIBD) of the skin and mucous membranes caused by autoantibodies to desmosomal components, desmoglein 1 and 3. Among immunosuppressant therapies, rituximab (RTX) is considered a highly effective treatment with a favorable safety profile, but it induces a prolonged B-cell depletion that can lead to higher susceptibility to infections. For this reason, concerns about its use during the pandemic have been raised. We describe a case of a pemphigus patient in which RTX-induced B cell depletion led to the severe inflammatory phase, whereas corticosteroid treatment allowed a favorable outcome.


Assuntos
Corticosteroides/uso terapêutico , Linfócitos B/imunologia , COVID-19/tratamento farmacológico , Pênfigo/imunologia , Rituximab/efeitos adversos , Corticosteroides/efeitos adversos , Linfócitos B/metabolismo , COVID-19/complicações , COVID-19/fisiopatologia , Feminino , Febre , Humanos , Imunoglobulina G/imunologia , Inflamação/tratamento farmacológico , Pessoa de Meia-Idade , Oxigenoterapia , Pênfigo/complicações , Pênfigo/tratamento farmacológico , Rituximab/uso terapêutico
17.
Front Immunol ; 12: 639329, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33959123

RESUMO

Background: Infection with the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a wide range of symptoms including gastrointestinal manifestations, and intestinal epithelial cells are a target of the virus. However, it is unknown how the intestinal immune system contributes to systemic immune responses in coronavirus disease 2019 (COVID-19). Methods: We characterized peripheral blood lymphocytes from patients with active COVID-19 and convalescent patients as well as healthy controls by flow cytometry. Results: The frequency and absolute number of circulating memory T and B cells expressing the gut homing integrin α4ß7 integrin was reduced during COVID-19, whether gastrointestinal symptoms were present or not. While total IgA-expressing B cells were increased, gut-imprinted B cells with IgA expression were stable. Conclusion: COVID-19 is associated with a decrease in circulating adaptive immune cells expressing the key gut homing marker α4ß7 suggesting that these cells are preferentially recruited to extra-intestinal tissues independently of α4ß7 or that the systemic immune response against SARS-CoV-2 is at least numerically dominated by extraintestinal, particularly pulmonary, immune cell priming.


Assuntos
Linfócitos B/metabolismo , COVID-19/imunologia , Integrina alfa4/metabolismo , Integrinas/metabolismo , SARS-CoV-2/imunologia , Linfócitos T/metabolismo , Adulto , Linfócitos B/imunologia , Biomarcadores/análise , COVID-19/patologia , Feminino , Humanos , Memória Imunológica/imunologia , Mucosa Intestinal/citologia , Mucosa Intestinal/imunologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia
18.
Nat Commun ; 12(1): 3079, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-34035262

RESUMO

Nanosensors have proven to be powerful tools to monitor single cells, achieving spatiotemporal precision even at molecular level. However, there has not been way of extending this approach to statistically relevant numbers of living cells. Herein, we design and fabricate nanosensor array in microfluidics that addresses this limitation, creating a Nanosensor Chemical Cytometry (NCC). nIR fluorescent carbon nanotube array is integrated along microfluidic channel through which flowing cells is guided. We can utilize the flowing cell itself as highly informative Gaussian lenses projecting nIR profiles and extract rich information. This unique biophotonic waveguide allows for quantified cross-correlation of biomolecular information with various physical properties and creates label-free chemical cytometer for cellular heterogeneity measurement. As an example, the NCC can profile the immune heterogeneities of human monocyte populations at attomolar sensitivity in completely non-destructive and real-time manner with rate of ~600 cells/hr, highest range demonstrated to date for state-of-the-art chemical cytometry.


Assuntos
Linfócitos B/metabolismo , Técnicas Biossensoriais/métodos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Microfluídica/métodos , Nanotecnologia/métodos , Nanotubos de Carbono/química , Algoritmos , Transporte Biológico , Linhagem Celular , Corantes Fluorescentes/química , Células HEK293 , Humanos , Peróxido de Hidrogênio/metabolismo , Análise Espectral Raman/métodos , Células U937
19.
Nat Commun ; 12(1): 2717, 2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-33976150

RESUMO

Circulating cell-free DNA (cfDNA) in the bloodstream originates from dying cells and is a promising noninvasive biomarker for cell death. Here, we propose an algorithm, CelFiE, to accurately estimate the relative abundances of cell types and tissues contributing to cfDNA from epigenetic cfDNA sequencing. In contrast to previous work, CelFiE accommodates low coverage data, does not require CpG site curation, and estimates contributions from multiple unknown cell types that are not available in external reference data. In simulations, CelFiE accurately estimates known and unknown cell type proportions from low coverage and noisy cfDNA mixtures, including from cell types composing less than 1% of the total mixture. When used in two clinically-relevant situations, CelFiE correctly estimates a large placenta component in pregnant women, and an elevated skeletal muscle component in amyotrophic lateral sclerosis (ALS) patients, consistent with the occurrence of muscle wasting typical in these patients. Together, these results show how CelFiE could be a useful tool for biomarker discovery and monitoring the progression of degenerative disease.


Assuntos
Algoritmos , Esclerose Amiotrófica Lateral/genética , Ácidos Nucleicos Livres/genética , Metilação de DNA , Epigênese Genética , Adulto , Esclerose Amiotrófica Lateral/sangue , Esclerose Amiotrófica Lateral/imunologia , Esclerose Amiotrófica Lateral/patologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Biomarcadores/sangue , Estudos de Casos e Controles , Ácidos Nucleicos Livres/sangue , Ácidos Nucleicos Livres/classificação , Feminino , Humanos , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Monócitos/imunologia , Monócitos/metabolismo , Músculo Esquelético/imunologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Especificidade de Órgãos , Gravidez , Trimestres da Gravidez/sangue , Trimestres da Gravidez/genética , Linfócitos T/imunologia , Linfócitos T/metabolismo
20.
Nat Commun ; 12(1): 2559, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33963182

RESUMO

Multiple myeloma (MM) is characterized by the uncontrolled proliferation of plasma cells. Despite recent treatment advances, it is still incurable as disease progression is not fully understood. To investigate MM and its immune environment, we apply single cell RNA and linked-read whole genome sequencing to profile 29 longitudinal samples at different disease stages from 14 patients. Here, we collect 17,267 plasma cells and 57,719 immune cells, discovering patient-specific plasma cell profiles and immune cell expression changes. Patients with the same genetic alterations tend to have both plasma cells and immune cells clustered together. By integrating bulk genomics and single cell mapping, we track plasma cell subpopulations across disease stages and find three patterns: stability (from precancer to diagnosis), and gain or loss (from diagnosis to relapse). In multiple patients, we detect "B cell-featured" plasma cell subpopulations that cluster closely with B cells, implicating their cell of origin. We validate AP-1 complex differential expression (JUN and FOS) in plasma cell subpopulations using CyTOF-based protein assays, and integrated analysis of single-cell RNA and CyTOF data reveals AP-1 downstream targets (IL6 and IL1B) potentially leading to inflammation regulation. Our work represents a longitudinal investigation for tumor and microenvironment during MM progression and paves the way for expanding treatment options.


Assuntos
Linfócitos B/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Mieloma Múltiplo/genética , Mieloma Múltiplo/imunologia , Recidiva Local de Neoplasia/genética , Microambiente Tumoral/imunologia , Idoso , Linfócitos B/citologia , Linfócitos B/imunologia , Linhagem da Célula , Evolução Clonal/genética , Estudos de Coortes , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica/imunologia , Haplótipos , Humanos , Interleucina-1beta/sangue , Interleucina-6/sangue , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Família Multigênica , Mieloma Múltiplo/sangue , Mieloma Múltiplo/patologia , Mutação , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/imunologia , Proteínas Proto-Oncogênicas c-fos/sangue , Proteínas Proto-Oncogênicas c-jun/sangue , RNA-Seq , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Análise de Célula Única
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