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1.
BMC Infect Dis ; 21(1): 57, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33435865

RESUMO

BACKGROUND: In December 2019, coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, Hubei, China. Moreover, it has become a global pandemic. This is of great value in describing the clinical symptoms of COVID-19 patients in detail and looking for markers which are significant to predict the prognosis of COVID-19 patients. METHODS: In this multicenter, retrospective study, 476 patients with COVID-19 were enrolled from a consecutive series. After screening, a total of 395 patients were included in this study. All-cause death was the primary endpoint. All patients were followed up from admission till discharge or death. RESULTS: The main symptoms observed in the study included fever on admission, cough, fatigue, and shortness of breath. The most common comorbidities were hypertension and diabetes mellitus. Patients with lower CD4+T cell level were older and more often male compared to those with higher CD4+T cell level. Reduced CD8+T cell level was an indicator of the severity of COVID-19. Both decreased CD4+T [HR:13.659; 95%CI: 3.235-57.671] and CD8+T [HR: 10.883; 95%CI: 3.277-36.145] cell levels were associated with in-hospital death in COVID-19 patients, but only the decrease of CD4+T cell level was an independent predictor of in-hospital death in COVID-19 patients. CONCLUSIONS: Reductions in lymphocytes and lymphocyte subsets were common in COVID-19 patients, especially in severe cases of COVID-19. It was the CD8+T cell level, not the CD4+T cell level, that reflected the severity of the patient's disease. Only reduced CD4+T cell level was independently associated with increased in-hospital death in COVID-19 patients. TRIAL REGISTRATION: Prognostic Factors of Patients With COVID-19, NCT04292964 . Registered 03 March 2020. Retrospectively registered.


Assuntos
Linfócitos T CD4-Positivos/citologia , /imunologia , Adulto , Idoso , Linfócitos T CD8-Positivos/citologia , /mortalidade , Comorbidade , Feminino , Seguimentos , Hospitalização , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Pandemias , Alta do Paciente , Prognóstico , Estudos Retrospectivos , /genética
2.
Nat Commun ; 12(1): 497, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33479216

RESUMO

Prokaryotic restriction enzymes, recombinases and Cas proteins are powerful DNA engineering and genome editing tools. However, in many primary cell types, the efficiency of genome editing remains low, impeding the development of gene- and cell-based therapeutic applications. A safe strategy for robust and efficient enrichment of precisely genetically engineered cells is urgently required. Here, we screen for mutations in the receptor for Diphtheria Toxin (DT) which protect human cells from DT. Selection for cells with an edited DT receptor variant enriches for simultaneously introduced, precisely targeted gene modifications at a second independent locus, such as nucleotide substitutions and DNA insertions. Our method enables the rapid generation of a homogenous cell population with bi-allelic integration of a DNA cassette at the selection locus, without clonal isolation. Toxin-based selection works in both cancer-transformed and non-transformed cells, including human induced pluripotent stem cells and human primary T-lymphocytes, as well as it is applicable also in vivo, in mice with humanized liver. This work represents a flexible, precise, and efficient selection strategy to engineer cells using CRISPR-Cas and base editing systems.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes/métodos , Engenharia Genética/métodos , Fator de Crescimento Semelhante a EGF de Ligação à Heparina/genética , Mutação , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Proliferação de Células/genética , Sobrevivência Celular/genética , Células Cultivadas , Células HCT116 , Células HEK293 , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos
3.
EBioMedicine ; 63: 103197, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33422991

RESUMO

BACKGROUND: SARS-CoV-2 has caused a global pandemic, infecting millions of people. A safe, effective vaccine is urgently needed and remains a global health priority. Subunit vaccines are used successfully against other viruses when administered in the presence of an effective adjuvant. METHODS: We evaluated three different clinically tested adjuvant systems in combination with the SARS-CoV-2 pre-fusion stabilized (S-2P) spike protein using a one-dose regimen in mice. FINDINGS: Whilst spike protein alone was only weakly immunogenic, the addition of either Aluminum hydroxide, a squalene based oil-in-water emulsion system (SE) or a cationic liposome-based adjuvant significantly enhanced antibody responses against the spike receptor binding domain (RBD). Kinetics of antibody responses differed, with SE providing the most rapid response. Neutralizing antibodies developed after a single immunization in all adjuvanted groups with ID50 titers ranging from 86-4063. Spike-specific CD4 T helper responses were also elicited, comprising mainly of IFN-γ and IL-17 producing cells in the cationic liposome adjuvanted group, and more IL-5- and IL-10-secreting cells in the AH group. INTERPRETATION: These results demonstrate that adjuvanted spike protein subunit vaccine is a viable strategy for rapidly eliciting SARS-CoV-2 neutralizing antibodies and CD4 T cell responses of various qualities depending on the adjuvant used, which can be explored in further vaccine development against COVID-19. FUNDING: This work was supported by the European Union Horizon 2020 research and innovation program under grant agreement no. 101003653.


Assuntos
Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais/metabolismo , Linfócitos T CD4-Positivos/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/química , Hidróxido de Alumínio/química , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , /virologia , Feminino , Imunização , Interferon gama/metabolismo , Interleucina-17/metabolismo , Lipossomos/química , Camundongos , Camundongos Endogâmicos C57BL , Glicoproteína da Espícula de Coronavírus/química , Esqualeno/química , Vacinas de Subunidades/imunologia
4.
Nat Commun ; 12(1): 99, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397934

RESUMO

CD4 and CD8 mark helper and cytotoxic T cell lineages, respectively, and serve as coreceptors for MHC-restricted TCR recognition. How coreceptor expression is matched with TCR specificity is central to understanding CD4/CD8 lineage choice, but visualising coreceptor gene activity in individual selection intermediates has been technically challenging. It therefore remains unclear whether the sequence of coreceptor gene expression in selection intermediates follows a stereotypic pattern, or is responsive to signaling. Here we use single cell RNA sequencing (scRNA-seq) to classify mouse thymocyte selection intermediates by coreceptor gene expression. In the unperturbed thymus, Cd4+Cd8a- selection intermediates appear before Cd4-Cd8a+ selection intermediates, but the timing of these subsets is flexible according to the strength of TCR signals. Our data show that selection intermediates discriminate MHC class prior to the loss of coreceptor expression and suggest a model where signal strength informs the timing of coreceptor gene activity and ultimately CD4/CD8 lineage choice.


Assuntos
Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Diferenciação Celular/imunologia , Linhagem da Célula/imunologia , Timo/citologia , Timo/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Citocinas/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Antígenos de Histocompatibilidade/metabolismo , Ativação Linfocitária/genética , Camundongos Endogâmicos C57BL , Análise de Componente Principal , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo
5.
Cell ; 183(4): 996-1012.e19, 2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-33010815

RESUMO

Limited knowledge is available on the relationship between antigen-specific immune responses and COVID-19 disease severity. We completed a combined examination of all three branches of adaptive immunity at the level of SARS-CoV-2-specific CD4+ and CD8+ T cell and neutralizing antibody responses in acute and convalescent subjects. SARS-CoV-2-specific CD4+ and CD8+ T cells were each associated with milder disease. Coordinated SARS-CoV-2-specific adaptive immune responses were associated with milder disease, suggesting roles for both CD4+ and CD8+ T cells in protective immunity in COVID-19. Notably, coordination of SARS-CoV-2 antigen-specific responses was disrupted in individuals ≥ 65 years old. Scarcity of naive T cells was also associated with aging and poor disease outcomes. A parsimonious explanation is that coordinated CD4+ T cell, CD8+ T cell, and antibody responses are protective, but uncoordinated responses frequently fail to control disease, with a connection between aging and impaired adaptive immune responses to SARS-CoV-2.


Assuntos
Imunidade Adaptativa , Antígenos Virais/imunologia , Infecções por Coronavirus/patologia , Pneumonia Viral/patologia , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Betacoronavirus/isolamento & purificação , Betacoronavirus/metabolismo , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Citocinas/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Índice de Gravidade de Doença , Adulto Jovem
6.
Nat Commun ; 11(1): 5005, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024109

RESUMO

Hypoxia-inducible factor 1α (HIF-1α) and HIF-2α are master transcription factors that regulate cellular responses to hypoxia, but the exact function in regulatory T (Treg) cells is controversial. Here, we show that Treg cell development is normal in mice with Foxp3-specific knockout (KO) of HIF-1α or HIF-2α. However, HIF-2α-KO (but not HIF-1α-KO) Treg cells are functionally defective in suppressing effector T cell-induced colitis and inhibiting airway hypersensitivity. HIF-2α-KO Treg cells have enhanced reprogramming into IL-17-secreting cells. We show crosstalk between HIF-2α and HIF-1α, and that HIF-2α represses HIF-1α expression. HIF-1α is upregulated in HIF-2α-KO Treg cells and further deletion of HIF-1α restores the inhibitory function of HIF-2α-KO Treg cells. Mice with Foxp3-conditional KO of HIF-2α are resistant to growth of MC38 colon adenocarcinoma and metastases of B16F10 melanoma. Together, these results indicate that targeting HIF-2α to destabilize Treg cells might be an approach for regulating the functional activity of Treg cells.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linfócitos T Reguladores/fisiologia , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Hiper-Reatividade Brônquica/genética , Linfócitos T CD4-Positivos/citologia , Diferenciação Celular , Reprogramação Celular , Colite/etiologia , Colite/patologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Feminino , Fatores de Transcrição Forkhead/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Interleucina-17/metabolismo , Masculino , Melanoma/genética , Melanoma/patologia , Camundongos Knockout , Linfócitos T Reguladores/metabolismo
7.
Nucleic Acids Res ; 48(19): 10890-10908, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-33021676

RESUMO

Although endogenous retroviruses (ERVs) are known to harbor cis-regulatory elements, their role in modulating cellular immune responses remains poorly understood. Using an RNA-seq approach, we show that several members of the ERV9 lineage, particularly LTR12C elements, are activated upon HIV-1 infection of primary CD4+ T cells. Intriguingly, HIV-1-induced ERVs harboring transcription start sites are primarily found in the vicinity of immunity genes. For example, HIV-1 infection activates LTR12C elements upstream of the interferon-inducible genes GBP2 and GBP5 that encode for broad-spectrum antiviral factors. Reporter assays demonstrated that these LTR12C elements drive gene expression in primary CD4+ T cells. In line with this, HIV-1 infection triggered the expression of a unique GBP2 transcript variant by activating a cryptic transcription start site within LTR12C. Furthermore, stimulation with HIV-1-induced cytokines increased GBP2 and GBP5 expression in human cells, but not in macaque cells that naturally lack the GBP5 gene and the LTR12C element upstream of GBP2. Finally, our findings suggest that GBP2 and GBP5 have already been active against ancient viral pathogens as they suppress the maturation of the extinct retrovirus HERV-K (HML-2). In summary, our findings uncover how human cells can exploit remnants of once-infectious retroviruses to regulate antiviral gene expression.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Retrovirus Endógenos/genética , Regulação da Expressão Gênica/imunologia , Infecções por HIV/genética , Regiões Promotoras Genéticas , Subpopulações de Linfócitos T/imunologia , Animais , Linfócitos T CD4-Positivos/citologia , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/imunologia , Células HEK293 , Infecções por HIV/imunologia , HIV-1 , Humanos , Macaca mulatta , Subpopulações de Linfócitos T/citologia
8.
Sci Rep ; 10(1): 17718, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-33077873

RESUMO

COVID-19 has been widely spreading. We aimed to examine adaptive immune cells in non-severe patients with persistent SARS-CoV-2 shedding. 37 non-severe patients with persistent SARS-CoV-2 presence that were transferred to Zhongnan hospital of Wuhan University were retrospectively recruited to the PP (persistently positive) group, which was further allocated to PPP group (n = 19) and PPN group (n = 18), according to their testing results after 7 days (N = negative). Epidemiological, demographic, clinical and laboratory data were collected and analyzed. Data from age- and sex-matched non-severe patients at disease onset (PA [positive on admission] patients, n = 37), and lymphocyte subpopulation measurements from matched 54 healthy subjects were extracted for comparison (HC). Compared with PA patients, PP patients had much improved laboratory findings. The absolute numbers of CD3+ T cells, CD4+ T cells, and NK cells were significantly higher in PP group than that in PA group, and were comparable to that in healthy controls. PPP subgroup had markedly reduced B cells and T cells compared to PPN group and healthy subjects. Finally, paired results of these lymphocyte subpopulations from 10 PPN patients demonstrated that the number of T cells and B cells significantly increased when the SARS-CoV-2 tests turned negative. Persistent SARS-CoV-2 presence in non-severe COVID-19 patients is associated with reduced numbers of adaptive immune cells. Monitoring lymphocyte subpopulations could be clinically meaningful in identifying fully recovered COVID-19 patients.


Assuntos
Linfócitos B/citologia , Infecções por Coronavirus/patologia , Pneumonia Viral/patologia , Linfócitos T/citologia , Adulto , Linfócitos B/imunologia , Linfócitos B/metabolismo , Betacoronavirus/isolamento & purificação , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Estudos de Casos e Controles , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Feminino , Humanos , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Masculino , Pandemias , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Linfócitos T/imunologia , Linfócitos T/metabolismo
9.
Nat Commun ; 11(1): 4402, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32879318

RESUMO

Genome-wide association studies have identified genetic variation contributing to complex disease risk. However, assigning causal genes and mechanisms has been more challenging because disease-associated variants are often found in distal regulatory regions with cell-type specific behaviours. Here, we collect ATAC-seq, Hi-C, Capture Hi-C and nuclear RNA-seq data in stimulated CD4+ T cells over 24 h, to identify functional enhancers regulating gene expression. We characterise changes in DNA interaction and activity dynamics that correlate with changes in gene expression, and find that the strongest correlations are observed within 200 kb of promoters. Using rheumatoid arthritis as an example of T cell mediated disease, we demonstrate interactions of expression quantitative trait loci with target genes, and confirm assigned genes or show complex interactions for 20% of disease associated loci, including FOXO1, which we confirm using CRISPR/Cas9.


Assuntos
Artrite Reumatoide/genética , Linfócitos T CD4-Positivos/metabolismo , Cromatina , Proteína Forkhead Box O1/genética , Doenças Autoimunes/genética , Linfócitos T CD4-Positivos/citologia , Cromatina/química , Cromatina/genética , Elementos Facilitadores Genéticos , Proteína Forkhead Box O1/metabolismo , Expressão Gênica , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Células HEK293 , Humanos , Cultura Primária de Células , Regiões Promotoras Genéticas , Locos de Características Quantitativas
10.
PLoS One ; 15(9): e0239396, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32966314

RESUMO

Despite recent progress in the treatment of rheumatoid arthritis (RA), many patients still fail to achieve remission or low disease activity. An imbalance between auto-reactive effector T cells (Teff) and regulatory T cells (Treg) may contribute to joint inflammation and damage in RA. Therefore, restoring this balance is a promising approach for the treatment of inflammatory arthritis. Accordingly, our group has previously shown that the combination of TGF-ß-releasing microparticles (MP), rapamycin-releasing MP, and IL-2-releasing MP (TRI MP) can effectively increase the ratio of Tregs to Teff in vivo and provide disease protection in several preclinical models. In this study TRI MP was evaluated in the collagen-induced arthritis (CIA) model. Although this formulation has been tested previously in models of destructive inflammation and transplantation, this is the first model of autoimmunity for which this therapy has been applied. In this context, TRI MP effectively reduced arthritis incidence, the severity of arthritis scores, and bone erosion. The proposed mechanism of action includes not only reducing CD4+ T cell proliferation, but also expanding a regulatory population in the periphery soon after TRI MP administration. These changes were reflected in the CD4+ T cell population that infiltrated the paws at the onset of arthritis and were associated with a reduction of immune infiltrate and inflammatory myeloid cells in the paws. TRI MP administration also reduced the titer of collagen antibodies, however the contribution of this reduced titer to disease protection remains uncertain since there was no correlation between collagen antibody titer and arthritis score.


Assuntos
Artrite Experimental/prevenção & controle , Interleucina-2/farmacologia , Microesferas , Sirolimo/farmacologia , Fator de Crescimento Transformador beta/farmacologia , Animais , Artrite Experimental/imunologia , Artrite Experimental/metabolismo , Autoanticorpos/metabolismo , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Contagem de Células , Citocinas/metabolismo , Modelos Animais de Doenças , Liberação Controlada de Fármacos , Interleucina-2/química , Masculino , Camundongos , Sirolimo/química , Fator de Crescimento Transformador beta/química
11.
Nucleic Acids Res ; 48(18): 10164-10183, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-32990751

RESUMO

T cells are central to the immune response against various pathogens and cancer cells. Complex networks of transcriptional and post-transcriptional regulators, including microRNAs (miRNAs), coordinate the T cell activation process. Available miRNA datasets, however, do not sufficiently dissolve the dynamic changes of miRNA controlled networks upon T cell activation. Here, we established a quantitative and time-resolved expression pattern for the entire miRNome over a period of 24 h upon human T-cell activation. Based on our time-resolved datasets, we identified central miRNAs and specified common miRNA expression profiles. We found the most prominent quantitative expression changes for miR-155-5p with a range from initially 40 molecules/cell to 1600 molecules/cell upon T-cell activation. We established a comprehensive dynamic regulatory network of both the up- and downstream regulation of miR-155. Upstream, we highlight IRF4 and its complexes with SPI1 and BATF as central for the transcriptional regulation of miR-155. Downstream of miR-155-5p, we verified 17 of its target genes by the time-resolved data recorded after T cell activation. Our data provide comprehensive insights into the range of stimulus induced miRNA abundance changes and lay the ground to identify efficient points of intervention for modifying the T cell response.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Ativação Linfocitária , MicroRNAs/metabolismo , Subpopulações de Linfócitos T/metabolismo , Adulto , Linfócitos T CD4-Positivos/citologia , Feminino , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Subpopulações de Linfócitos T/citologia , Adulto Jovem
12.
PLoS One ; 15(9): e0239399, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32946499

RESUMO

HIV-1 infection exhibits a significant sex bias. This study aimed at identifying and examining lymphocyte associated sex differences in HIV-1 pathogenesis using a data-driven approach. To select targets for investigating sex differences in lymphocytes, data of microarray experiments and literature mining were integrated. Data from three large-scale microarray experiments were obtained from NCBI/GEO and screened for sex differences in gene expression. Literature mining was employed to identify sex biased genes in the microarray data, which were relevant to HIV-1 pathogenesis and lymphocyte biology. Sex differences in gene expression of selected genes were investigated by RT-qPCR and flowcytometry in healthy individuals and persons living with HIV-1. A significant and consistent sex bias was identified in 31 genes, the majority of which were related to immunity and expressed at higher levels in women. Using literature mining, three genes (DPP4, FCGR1A and SOCS3) were selected for analysis by qPCR because of their relevance to HIV, as well as, B and T cell biology. DPP4 exhibited the most significant sex bias in mRNA expression (p = 0.00029). Therefore, its expression was further analyzed on B and T cells using flowcytometry. In HIV-1 infected controllers and healthy individuals, frequencies of CD4+DPP4+ T cells were higher in women compared to men (p = 0.037 and p = 0.027). In women, CD4 T cell counts correlated with a predominant decreased in DPP4+CD4+ T cells (p = 0.0032). Sex differences in DPP4 expression abrogated in progressive HIV-1 infection. In conclusion, we found sex differences in the pathobiology of T cells in HIV-1 infection using a data-driven approach. Our results indicate that DPP4 expression on CD4+ T cells might contribute to the immunological sex differences observed in chronic HIV­1 infection.


Assuntos
Linfócitos T CD4-Positivos/citologia , Mineração de Dados , Dipeptidil Peptidase 4/metabolismo , Infecções por HIV/genética , Infecções por HIV/imunologia , HIV-1/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos , Adulto , Linfócitos T CD4-Positivos/metabolismo , Contagem de Células , Progressão da Doença , Feminino , Humanos , Masculino , Distribuição por Sexo
13.
Proc Natl Acad Sci U S A ; 117(36): 22357-22366, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32839313

RESUMO

Fever is a conserved and prominent response to infection. Yet, the issue of how CD4 T cell responses are modulated if they occur at fever temperatures remains poorly addressed. We have examined the priming of naive CD4 T cells in vitro at fever temperatures, and we report notable fever-mediated modulation of their cytokine commitment. When naive CD4 T cells were primed by plate-bound anti-CD3 and anti-CD28 monoclonal antibodies at moderate fever temperature (39 °C), they enhanced commitment to IL4/5/13 (Th2) and away from IFNg (Th1). This was accompanied by up-regulation of the Th2-relevant transcription factor GATA3 and reduction in the Th1-relevant transcription factor Tbet. Fever sensing by CD4 T cells involved transient receptor potential vanilloid cation channels (TRPVs) since TRPV1/TRPV4 antagonism blocked the febrile Th2 switch, while TRPV1 agonists mediated a Th2 switch at 37 °C. The febrile Th2 switch was IL4 independent, but a γ-secretase inhibitor abrogated it, and it was not found in Notch1-null CD4 T cells, identifying the Notch pathway as a major mediator. However, when naive CD4 T cells were primed via antigen and dendritic cells (DCs) at fever temperatures, the Th2 switch was abrogated via increased production of IL12 from DCs at fever temperatures. Thus, immune cells directly sense fever temperatures with likely complex physiological consequences.


Assuntos
Linfócitos T CD4-Positivos/fisiologia , Diferenciação Celular/fisiologia , Febre/fisiopatologia , Receptores Notch/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Temperatura Corporal/fisiologia , Linfócitos T CD4-Positivos/citologia , Células Cultivadas , Temperatura Alta , Camundongos , Modelos Biológicos
14.
Nature ; 584(7822): 624-629, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32788723

RESUMO

Conventional type 1 dendritic cells (cDC1)1 are thought to perform antigen cross-presentation, which is required to prime CD8+ T cells2,3, whereas cDC2 are specialized for priming CD4+ T cells4,5. CD4+ T cells are also considered to help CD8+ T cell responses through a variety of mechanisms6-11, including a process whereby CD4+ T cells 'license' cDC1 for CD8+ T cell priming12. However, this model has not been directly tested in vivo or in the setting of help-dependent tumour rejection. Here we generated an Xcr1Cre mouse strain to evaluate the cellular interactions that mediate tumour rejection in a model requiring CD4+ and CD8+ T cells. As expected, tumour rejection required cDC1 and CD8+ T cell priming required the expression of major histocompatibility class I molecules by cDC1. Unexpectedly, early priming of CD4+ T cells against tumour-derived antigens also required cDC1, and this was not simply because they transport antigens to lymph nodes for processing by cDC2, as selective deletion of major histocompatibility class II molecules in cDC1 also prevented early CD4+ T cell priming. Furthermore, deletion of either major histocompatibility class II or CD40 in cDC1 impaired tumour rejection, consistent with a role for cognate CD4+ T cell interactions and CD40 signalling in cDC1 licensing. Finally, CD40 signalling in cDC1 was critical not only for CD8+ T cell priming, but also for initial CD4+ T cell activation. Thus, in the setting of tumour-derived antigens, cDC1 function as an autonomous platform capable of antigen processing and priming for both CD4+ and CD8+ T cells and of the direct orchestration of their cross-talk that is required for optimal anti-tumour immunity.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Apresentação Cruzada , Células Dendríticas/imunologia , Neoplasias/imunologia , Animais , Apresentação do Antígeno/imunologia , Linfócitos T CD4-Positivos/citologia , Antígenos CD40/imunologia , Antígenos CD40/metabolismo , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Feminino , Antígenos de Histocompatibilidade Classe II/imunologia , Camundongos , Transdução de Sinais
15.
Nat Commun ; 11(1): 3366, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32632165

RESUMO

CD4+ T lymphocytes consist of naïve, antigen-specific memory, and memory-phenotype (MP) cell compartments at homeostasis. We recently showed that MP cells exert innate-like effector function during host defense, but whether MP CD4+ T cells are functionally heterogeneous and, if so, what signals specify the differentiation of MP cell subpopulations under homeostatic conditions is still unclear. Here we characterize MP lymphocytes as consisting of T-bethigh, T-betlow, and T-bet- subsets, with innate, Th1-like effector activity exclusively associated with T-bethigh cells. We further show that the latter population depends on IL-12 produced by CD8α+ type 1 dendritic cells (DC1) for its differentiation. Finally, our data demonstrate that this tonic IL-12 production requires TLR-MyD88 signaling independent of foreign agonists, and is further enhanced by CD40-CD40L interactions between DC1 and CD4+ T lymphocytes. We propose that optimal differentiation of T-bethigh MP lymphocytes at homeostasis is driven by self-recognition signals at both the DC and Tcell levels.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/imunologia , Homeostase/imunologia , Memória Imunológica/imunologia , Proteínas com Domínio T/imunologia , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Antígenos CD40/imunologia , Antígenos CD40/metabolismo , Ligante de CD40/genética , Ligante de CD40/imunologia , Ligante de CD40/metabolismo , Antígenos CD8/imunologia , Antígenos CD8/metabolismo , Comunicação Celular/imunologia , Células Dendríticas/citologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Interleucina-12/genética , Interleucina-12/imunologia , Interleucina-12/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Transdução de Sinais/imunologia , Proteínas com Domínio T/metabolismo , Células Th1/citologia , Células Th1/imunologia , Células Th1/metabolismo
16.
EBioMedicine ; 57: 102885, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32650275

RESUMO

BACKGROUND: Elucidating the role of T cell responses in COVID-19 is of utmost importance to understand the clearance of SARS-CoV-2 infection. METHODS: 30 hospitalized COVID-19 patients and 60 age- and gender-matched healthy controls (HC) participated in this study. We used two comprehensive 11-colour flow cytometric panels conforming to Good Laboratory Practice and approved for clinical diagnostics. FINDINGS: Absolute numbers of lymphocyte subsets were differentially decreased in COVID-19 patients according to clinical severity. In severe disease (SD) patients, all lymphocyte subsets were reduced, whilst in mild disease (MD) NK, NKT and γδ T cells were at the level of HC. Additionally, we provide evidence of T cell activation in MD but not SD, when compared to HC. Follow up samples revealed a marked increase in effector T cells and memory subsets in convalescing but not in non-convalescing patients. INTERPRETATION: Our data suggest that activation and expansion of innate and adaptive lymphocytes play a major role in COVID-19. Additionally, recovery is associated with formation of T cell memory as suggested by the missing formation of effector and central memory T cells in SD but not in MD. Understanding T cell-responses in the context of clinical severity might serve as foundation to overcome the lack of effective anti-viral immune response in severely affected COVID-19 patients and can offer prognostic value as biomarker for disease outcome and control. FUNDING: Funded by State of Lower Saxony grant 14-76,103-184CORONA-11/20 and German Research Foundation, Excellence Strategy - EXC2155"RESIST"-Project ID39087428, and DFG-SFB900/3-Project ID158989968, grants SFB900-B3, SFB900-B8.


Assuntos
Betacoronavirus/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por Coronavirus/imunologia , Ativação Linfocitária/imunologia , Pneumonia Viral/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Feminino , Humanos , Memória Imunológica/imunologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Pandemias , Prognóstico , Índice de Gravidade de Doença , Adulto Jovem
17.
Cytometry A ; 97(8): 772-776, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32542842

RESUMO

A reduced peripheral blood absolute lymphocyte count with an elevated neutrophil count has been a consistent observation in hospitalized coronavirus disease 2019 (COVID-19) patients. In this brief meta-analysis, the reduction of lymphocyte subset counts in COVID-19 patients was investigated across 20 peer-reviewed studies meeting criteria for reporting lymphocyte subset counts and COVID-19 disease severity. CD4+ T cell, CD8+ T cell, B cell, NK cell, and total lymphocyte cell counts all showed statistically significant reduction in patients with severe/critical COVID-19 disease compared to mild/moderate disease. T-cell subsets showed the largest standardized magnitude of change. In some studies, multivariate analysis has shown that CD4 and/or CD8 T-cells counts are independently predictive of patient outcomes. © 2020 International Society for Advancement of Cytometry.


Assuntos
Linfócitos B/citologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Infecções por Coronavirus/sangue , Células Matadoras Naturais/citologia , Pneumonia Viral/sangue , Subpopulações de Linfócitos T/citologia , Betacoronavirus , Humanos , Contagem de Linfócitos , Neutrófilos/citologia , Pandemias
18.
Clin Chim Acta ; 510: 1-4, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32598880

RESUMO

This study mainly focused on the very serious COVID-19 epidemic situation at present and provided a new insight for the treatment and monitor of patients with COVID-19. Through this meta-analysis, we could draw a conclusion that less expression of blood CD4+ and CD8+ T cells count might reflect the severity of infection and often accompanied by a poor prognosis. Hence, we inferred blood CD4+ and CD8+ T cells count could be a promising biomarker for disease assessment and monitor of patients with COVID-19.


Assuntos
Linfócitos T CD4-Positivos/citologia , Linfócitos T CD8-Positivos/citologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/imunologia , Regulação da Expressão Gênica , Pneumonia Viral/diagnóstico , Pneumonia Viral/imunologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Prognóstico
19.
J Med Chem ; 63(11): 6003-6027, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32421343

RESUMO

We disclose a study on nucleoside triphosphate (NTP) analogues in which the γ-phosphate is covalently modified by two different biodegradable masking units and d4T as nucleoside analogue that enable the delivery of d4TTP with high selectivity in phosphate buffer (pH 7.3) and by enzyme-triggered reactions in human CD4+ T-lymphocyte CEM cell extracts. This allows the bypass of all steps normally needed in the intracellular phosphorylation. These TriPPPro-nucleotides comprising an acyloxybenzyl (AB; ester) or an alkoxycarbonyloxybenzyl (ACB; carbonate) in combination with an ACB moiety are described as NTP delivery systems. The introduction of these two different groups led to the selective formation of γ-(ACB)-d4TTPs by chemical hydrolysis and in particular by cell extract enzymes. γ-(AB)-d4TTPs are faster cleaved than γ-(ACB)-d4TTPs. In antiviral assays, the compounds are highly active against HIV-1 and HIV-2 in wild-type CEM/O cells and more importantly in thymidine kinase-deficient CD4+ T-cells (CEM/TK-).


Assuntos
Fármacos Anti-HIV/farmacologia , HIV-1/efeitos dos fármacos , HIV-2/efeitos dos fármacos , Nucleotídeos/química , Pró-Fármacos/química , Animais , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacocinética , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Esterases/metabolismo , Meia-Vida , Humanos , Hidrólise , Fígado/enzimologia , Nucleotídeos/metabolismo , Nucleotídeos/farmacologia , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacologia , Suínos
20.
EMBO Mol Med ; 12(6): e12661, 2020 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-32379923

RESUMO

The ongoing severe acute respiratory sickness coronavirus 2 (SARS-CoV-2) pandemic has resulted in more than 3,600,000 detected cases of COVID-19 illness and nearly 260,000 deaths worldwide as of May 6, 2020. Recently, BCG vaccination was shown to correlate with reduced COVID-19 case fatality rates (preprint: Miller et al, 2020; preprint: Sala & Miyakawa, 2020; https://www.jsatonotes.com/2020/03/if-i-were-north-americaneuropeanaustral.html). The most recent data from publicly available resources also indicate that both COVID-19 incidence and total deaths are strongly associated with the presence or absence of national mandatory BCG vaccination programs. As seen in Table 1, seven of eight countries with very low numbers of total deaths (< 40 per 1 million population) adopted a mandatory BCG vaccination program using one of a set of 6 separate BCG strains (Table 1). In contrast, COVID-19 mortality was markedly higher in countries where BCG vaccination is not widely administered or is given only to high-risk groups. COVID-19 mortality was also higher in countries where widespread BCG vaccination was discontinued more than 20 years ago and in countries that used the BCG Denmark strain regularly or temporarily. This raises the question of whether BCG vaccination and reduced COVID-19 mortality are causally related. An additional question is why different BCG strains may be variably associated with mortality.


Assuntos
Vacina BCG/imunologia , Infecções por Coronavirus/patologia , Pneumonia Viral/patologia , Betacoronavirus/isolamento & purificação , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/virologia , Citocinas/metabolismo , Humanos , Mycobacterium bovis/genética , Mycobacterium bovis/imunologia , Mycobacterium bovis/metabolismo , Pandemias , Pneumonia Viral/mortalidade , Pneumonia Viral/virologia , Risco , Sorogrupo , Análise de Sobrevida , Vacinação
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