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1.
Biosensors (Basel) ; 13(5)2023 May 11.
Artigo em Inglês | MEDLINE | ID: covidwho-20231120

RESUMO

Increased frequency of CD4+CD25+ regulatory T-cells (Treg) has been associated with disease progression in chronic lymphocytic leukemia (CLL). Flow cytometric methods, which allow for the simultaneous analysis of their specific transcription factor Foxp3 and activated STAT proteins, together with proliferation can help to elucidate the signaling mechanisms driving Treg expansion and suppression of FOXP3- conventional CD4+T-cells (Tcon). Herein, we first report a novel approach in which STAT5 phosphorylation (pSTAT5) and proliferation (BrdU-FITC incorporation) could be analyzed specifically in FOXP3+ and FOXP3- responding cells after CD3/CD28 stimulation. The addition of magnetically purified CD4+CD25+ T-cells from healthy donors to cocultured autologous CD4+CD25- T-cells resulted in suppression of Tcon cell cycle progression accompanied by a decrease in pSTAT5. Next, a method using imaging flow cytometry is presented for the detection of cytokine-dependent pSTAT5 nuclear translocation in FOXP3-expressing cells. Finally, we discuss our experimental data obtained by combining Treg pSTAT5 analysis and antigen-specific stimulation with SARS-CoV-2 antigens. Applying these methods on samples from patients revealed Treg responses to antigen-specific stimulation and significantly higher basal pSTAT5 in CLL patients treated with immunochemotherapy. Thus, we speculate that through the use of this pharmacodynamic tool, the efficacy of immunosuppressive drugs and their possible off-target effects can be assessed.


Assuntos
COVID-19 , Leucemia Linfocítica Crônica de Células B , Humanos , Linfócitos T Reguladores/metabolismo , Leucemia Linfocítica Crônica de Células B/metabolismo , Citometria de Fluxo , SARS-CoV-2/metabolismo , Fator de Transcrição STAT5/metabolismo , Fator de Transcrição STAT5/farmacologia , Fatores de Transcrição Forkhead/metabolismo , Fatores de Transcrição Forkhead/farmacologia
2.
Orv Hetil ; 163(52): 2062-2066, 2022 Dec 25.
Artigo em Húngaro | MEDLINE | ID: covidwho-2309139

RESUMO

INTRODUCTION: In our study, we aimed to investigate whether the COVID-19 infection itself or the vaccination against it affect the differentiation of T cells in the thymus, and whether the reduction in T cell counts observed in the blood of COVID-19-infected individuals is also observed at the tissue level in the thymus. METHOD: Data from a total of 55 thymectomy patients were processed to create three groups: 1) the pre-COVID-19 (PC) group included 22 patients, 12 women and 10 men, who underwent thymectomy between 2008 and 2013; 2) in the no-COVID-19 (NC) group (patients without verified infection or vaccination), 20 patients, 11 women and 9 men, underwent thymectomy in 2020-2021; 3) the vaccinated or infected COVID-19 (VIC) group included 13 patients, 4 women and 9 men, who underwent thymectomy also in 2020-2021. The pathological samples were immunohistochemically tested for CD4, CD8, CD25 and FOXP3 to verify the helper, cytotoxic and regulatory T cells. RESULTS: The VIC group had significantly lower values for CD4, compared to the PC and NC groups. The FOXP3 value was significantly lower in the VIC and NC groups compared to the PC group. No significant differences were found for CD8 and CD25 between the groups studied. DISCUSSION: The COVID-19 infection or vaccination affects the T cell composition of the thymus. Decreased expression of CD4 has been demonstrated in the VIC group, which confirms a decrease in the T cell counts that also occurs in the thymus. The low FOXP3 levels observed in the NC group during the COVID-19 era, compared to the PC group, may be indicative of a high rate of asymptomatic coronavirus infections and a worsening of immunetolerance. CONCLUSION: First in the world, we have verified that the helper T cell composition of the thymus in COVID-19 infection era is reduced, and in the asymptomatic patients the immune function is decreased as well. Orv Hetil. 2022; 163(52): 2062-2066.


Assuntos
COVID-19 , Pandemias , Linfócitos T , Timo , Feminino , Humanos , Masculino , COVID-19/imunologia , COVID-19/prevenção & controle , Fatores de Transcrição Forkhead/metabolismo , Timo/imunologia , Contagem de Linfócitos , Linfócitos T/imunologia , Vacinação
3.
J Immunol ; 210(11): 1687-1699, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: covidwho-2300707

RESUMO

Although CD4+CD25+FOXP3+ regulatory T (TREG) cells have been studied in patients with COVID-19, changes in the TREG cell population have not been longitudinally examined during the course of COVID-19. In this study, we longitudinally investigated the quantitative and qualitative changes in the TREG cell population in patients with COVID-19. We found that the frequencies of total TREG cells and CD45RA-FOXP3hi activated TREG cells were significantly increased 15-28 d postsymptom onset in severe patients, but not in mild patients. TREG cells from severe patients exhibited not only increased proliferation but also enhanced apoptosis, suggesting functional derangement of the TREG cell population during severe COVID-19. The suppressive functions of the TREG cell population did not differ between patients with severe versus mild COVID-19. The frequency of TREG cells inversely correlated with SARS-CoV-2-specific cytokine production by CD4+ T cells and their polyfunctionality in patients with mild disease, suggesting that TREG cells are major regulators of virus-specific CD4+ T cell responses during mild COVID-19. However, such correlations were not observed in patients with severe disease. Thus, in this study, we describe distinctive changes in the TREG cell population in patients with severe and mild COVID-19. Our study provides a deep understanding of host immune responses upon SARS-CoV-2 infection in regard to TREG cells.


Assuntos
COVID-19 , Linfócitos T Reguladores , Humanos , SARS-CoV-2 , Linfócitos T CD4-Positivos , Subunidade alfa de Receptor de Interleucina-2 , Fatores de Transcrição Forkhead
4.
Int Arch Allergy Immunol ; 184(3): 291-301, 2023.
Artigo em Inglês | MEDLINE | ID: covidwho-2290461

RESUMO

INTRODUCTION: The favorable effects of probiotics have been demonstrated in allergic disorders. However, the underlying immunological mechanisms are poorly understood. In the present study, we investigated the improvement of clinical symptoms and immunological balance after receiving probiotics in patients with asthma. METHODS: The present study was a randomized, double-blind, placebo-controlled trial in which 40 patients with asthma were enrolled. They were treated with probiotics or placebo: 1 capsule/day for 8 weeks. Pulmonary function test, percentage of CD4+ CD25+ FoxP3+ Tregs, and gene expression of T-bet, GATA-3, RORγt, and Foxp3 in PBMCs were assessed at baseline and after treatment. RESULTS: Our results showed a significant increase in the expression of FoxP3 and CD4+ CD25+ FoxP3+ Tregs population, while RORγt and GATA3 expression were reduced. In addition, pulmonary function tests showed a significant improvement in forced expiratory volume and forced vital capacity after receiving probiotics. DISCUSSION/CONCLUSION: Our findings demonstrate that 8-week treatment with probiotic supplementation can control T-helper 2-predominant and Th17 pro-inflammatory responses and improve forced vital and forced expiratory volume in asthmatic patients. It seems probiotics can be used besides common treatments for patients with asthma.


Assuntos
Asma , Probióticos , Humanos , Linfócitos T Reguladores , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Suplementos Nutricionais , Probióticos/uso terapêutico , Fatores de Transcrição Forkhead/genética
5.
Immunol Cell Biol ; 101(3): 191-203, 2023 03.
Artigo em Inglês | MEDLINE | ID: covidwho-2249670

RESUMO

Type 1 diabetes (T1D) is a condition characterized by an absolute deficiency of insulin. Loss of insulin-producing pancreatic islet ß cells is one of the many causes of T1D. Viral infections have long been associated with new-onset T1D and the balance between virulence and host immunity determines whether the viral infection would lead to T1D. Herein, we detail the dynamic interaction of pancreatic ß cells with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the host immune system with respect to new-onset T1D. Importantly, ß cells express the crucial entry receptors and multiple studies confirmed that ß cells are infected by SARS-CoV-2. Innate immune system effectors, such as natural killer cells, can eliminate such infected ß cells. Although CD4+ CD25+ FoxP3+ regulatory T (TREG ) cells provide immune tolerance to prevent the destruction of the islet ß-cell population by autoantigen-specific CD8+ T cells, it can be speculated that SARS-CoV-2 infection may compromise self-tolerance by depleting TREG -cell numbers or diminishing TREG -cell functions by repressing Forkhead box P3 (FoxP3) expression. However, the expansion of ß cells by self-duplication, and regeneration from progenitor cells, could effectively replace lost ß cells. Appearance of islet autoantibodies following SARS-CoV-2 infection was reported in a few cases, which could imply a breakdown of immune tolerance in the pancreatic islets. However, many of the cases with newly diagnosed autoimmune response following SARS-CoV-2 infection also presented with significantly high HbA1c (glycated hemoglobin) levels that indicated progression of an already set diabetes, rather than new-onset T1D. Here we review the potential underlying mechanisms behind loss of functional ß-cell mass as a result of SARS-CoV-2 infection that can trigger new-onset T1D.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 1 , Viroses , Humanos , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T Reguladores , SARS-CoV-2/metabolismo , Insulina/metabolismo , Fatores de Transcrição Forkhead/metabolismo
6.
Int Arch Allergy Immunol ; 184(6): 557-566, 2023.
Artigo em Inglês | MEDLINE | ID: covidwho-2247754

RESUMO

INTRODUCTION: The prevalence of coronavirus disease 2019 (COVID-19) has rapidly increased worldwide. More investigation is needed to progress toward understanding the exact role of immune responses in the pathology of the disease, leading to improved anticipation and treatment options. METHODS: In the present study, we examined the relative expression of T-bet, GATA3, RORγt, and FoxP3 transcription factors as well as laboratory indicators in 79 hospitalized patients along with 20 healthy subjects as a control group. In order to make an exact comparison between various degrees of severity of disease, patients were divided into critical (n = 12) and severe (n = 67) groups. To evaluate the expression of genes of interest by performing real-time PCR, blood samples were obtained from each participant. RESULTS: We found a significant increase in the expression of T-bet, GATA3, and RORγt and a reduction in the expression of FoxP3 in the critically ill patients compared to the severe and control groups. Also, we noticed that the GATA3 and RORγt expressions were elevated in the severe group in comparison with healthy subjects. Additionally, the GATA3 and RORγt expressions showed a positive correlation with elevation in CRP and hepatic enzyme concentration. Moreover, we observed that the GATA3 and RORγt expressions were the independent risk factors for the severity and outcome of COVID-19. DISCUSSION: The present study showed that the overexpression of T-bet, GATA3, and RORγt, as well as a decrease in the FoxP3 expression was associated with the severity and fatal outcome of COVID-19.


Assuntos
COVID-19 , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares , Humanos , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismo , Fatores Imunológicos , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Fator de Transcrição GATA3/genética , Fator de Transcrição GATA3/metabolismo
7.
Immunobiology ; 228(2): 152343, 2023 03.
Artigo em Inglês | MEDLINE | ID: covidwho-2210509

RESUMO

INTRODUCTION: It has been demonstrated that the patients with severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) suffer from severe inflammation. Due to the ethnics, the immune responses may be different. Additionally, microRNAs may alter immune responses in the patients. The current study was aimed to evaluate the expression of T helper subsets-related transcription factors, some T helper 17 (Th17) products, and two microRNAs, including miR-155 and miR-194, in the Iranian hospitalized patients. METHODS: In this study, T-box expressed in T cells (T-bet), GATA binding protein 3, The retinoid orphan receptor gamma t (RORγt), forkhead box P3 (FOXP3), interleukin (IL)-17A, IL-8, and CC ligand 20 (CCL20) mRNA levels and, miR-155 and miR-194 levels were evaluated in 70 patients suffered from severe coronavirus disease 2019 (COVID-19) and 70 healthy subjects using Real-Time qPCR technique. RESULTS: The findings showed that RORγt, and FOXP3 mRNA levels were significantly increased, while IL-17A, IL-8, and CCL20 mRNA levels were significantly decreased in the hospitalized SARS-CoV-2 infected patients. Although the levels of miR-155 and miR-194 were not different between groups, miR-194 has negative and positive correlations with RORγt and IL-17A in the Iranian healthy controls. CONCLUSION: This study reports although RORγt was up-regulated, IL-17A, IL-8, and CCL20 mRNA levels were significantly decreased in the hospitalized SARS-CoV-2 infected patients. It may be concluded that up-regulation of FOXP3, via development of T regulatory lymphocytes suppresses Th17 functions and neutralizes Th17 activities. MiR-194 may play crucial roles in regulation of RORγt and IL-17A expression in healthy people, the phenomenon that is disrupted in the severe SARS-CoV-2 infected patients.


Assuntos
COVID-19 , MicroRNAs , Linfócitos T Reguladores , Células Th17 , Humanos , COVID-19/imunologia , COVID-19/metabolismo , COVID-19/patologia , Fatores de Transcrição Forkhead/metabolismo , Interleucina-17/metabolismo , Interleucina-8/metabolismo , Irã (Geográfico) , MicroRNAs/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , RNA Mensageiro/genética , SARS-CoV-2/genética
8.
Front Immunol ; 13: 984476, 2022.
Artigo em Inglês | MEDLINE | ID: covidwho-2154723

RESUMO

Regulatory T cells that express the transcription factor Foxp3 (Treg cells) are a highly heterogenous population of immunoregulatory cells critical for maintaining immune homeostasis and preventing immunopathology during infections. Tissue resident Treg (TR-Treg) cells are maintained within nonlymphoid tissues and have been shown to suppress proinflammatory tissue resident T cell responses and promote tissue repair. Human populations are repetitively exposed to influenza infections and lung tissue resident effector T cell responses are associated with flu-induced long-term pulmonary sequelae. The kinetics of TR-Treg cell development and molecular features of TR-Treg cells during repeated and/or long-term flu infections are unclear. Utilizing a Foxp3RFP/IL-10GFP dual reporter mouse model along with intravascular fluorescent in vivo labeling, we characterized the TR-Treg cell responses to repetitive heterosubtypic influenza infections. We found lung tissue resident Treg cells accumulated and expressed high levels of co-inhibitory and co-stimulatory receptors post primary and secondary infections. Blockade of PD-1 or ICOS signaling reveals that PD-1 and ICOS signaling pathways counter-regulate TR-Treg cell expansion and IL-10 production, during secondary influenza infection. Furthermore, the virus-specific TR-Treg cell response displayed distinct kinetics, when compared to conventional CD4+ tissue resident memory T cells, during secondary flu infection. Our results provide insight into the tissue resident Foxp3+ regulatory T cell response during repetitive flu infections, which may be applicable to other respiratory infectious diseases such as tuberculosis and COVID.


Assuntos
COVID-19 , Animais , Fatores de Transcrição Forkhead/metabolismo , Humanos , Proteína Coestimuladora de Linfócitos T Induzíveis/metabolismo , Interleucina-10 , Camundongos , Infecções por Orthomyxoviridae , Receptor de Morte Celular Programada 1/metabolismo , Linfócitos T Reguladores
9.
Bull Exp Biol Med ; 173(6): 740-744, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: covidwho-2103946

RESUMO

The possibility of finding persistent SARS-CoV-2 viral particles in human peripheral blood leukocytes after a novel coronavirus infection was shown. The results of droplet digital PCR showed that 19 of 24 examined subjects had from 4 to 555 copies of the Nsp4 SARS-CoV-2 gene in 5-6 months after infection. The presence of this transcript in peripheral blood leukocytes was associated with reduced expression of FOXP3 gene and increased level of RORγ gene mRNA. The copy number of the Nsp4 gene negatively correlated with the level of FOXP3 gene mRNA (r=-0.45; p=0.028), but showed a positive correlation with the DANCR long non-coding RNA (r=0.94; p<0.001). In SARS-CoV-2-positive healthy individuals, the level of TLR2, NLRP3, and IL1B gene transcripts was higher than in SARS-CoV-2-negative donors. The presence of SARS-CoV-2 in a persistent form is probably associated with impaired immunosuppression and the development of chronic inflammation in apparently healthy volunteers after a new coronavirus infection.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , RNA Viral/genética , COVID-19/genética , RNA Mensageiro/genética , Leucócitos , Fatores de Transcrição Forkhead
10.
Front Immunol ; 13: 916411, 2022.
Artigo em Inglês | MEDLINE | ID: covidwho-2022705

RESUMO

Coronavirus disease 2019 (COVID-19) has been raging all around the world since the beginning of 2020, and leads to acute respiratory distress syndrome (ARDS) with strong cytokine storm which contributes to widespread tissue damage and even death in severe patients. Over-activated immune response becomes one of the characteristics of severe COVID-19 patients. Regulatory T cells (Treg) play an essential role in maintaining the immune homeostasis, which restrain excessive inflammation response. So FOXP3+ Tregs might participate in the suppression of inflammation caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Besides suppressive function, tissue resident Tregs are also responsible for tissue repair. In this review, we mainly summarize the latest research focusing on the change of FOXP3+ Tregs in the COVID-19 patients, discuss the relationship between disease severity and number change of Tregs and speculate the potential role of FOXP3+ Tregs during SARS-CoV-2 infection. Furthermore, we introduce some potential Treg-based therapies to improve patients' outcomes, which include small molecular drugs, antibody drugs, CAR-Treg and cytokine treatment. We hope to reduce tissue damage of severe COVID-19 patients and offer better prognosis through Treg-based therapy.


Assuntos
COVID-19 , Linfócitos T Reguladores , COVID-19/imunologia , Síndrome da Liberação de Citocina , Fatores de Transcrição Forkhead , Humanos , Inflamação , SARS-CoV-2 , Linfócitos T Reguladores/imunologia
11.
J Med Virol ; 94(5): 2089-2101, 2022 05.
Artigo em Inglês | MEDLINE | ID: covidwho-1626431

RESUMO

COVID-19 is a disease characterized by acute respiratory failure and is a major health problem worldwide. Here, we aimed to investigate the role of CD39 expression in Treg cell subsets in COVID-19 immunopathogenesis and its relationship to disease severity. One hundred and ninety COVID-19 patients (juveniles, adults) and 43 volunteers as healthy controls were enrolled in our study. Flow cytometric analysis was performed using a 10-color monoclonal antibody panel from peripheral blood samples. In adult patients, CD39+ Tregs increased with disease severity. In contrast, CD39+ Tregs were decreased in juvenile patients in an age-dependent manner. Overall, our study reveals an interesting profile of CD39-expressing Tregs in adult and juvenile cases of COVID-19. Our results provide a better understanding of the possible role of Tregs in the mechanism of immune response in COVID-19 cases.


Assuntos
Apirase , COVID-19 , Linfócitos T Reguladores , Adulto , Apirase/biossíntese , Apirase/imunologia , Apirase/metabolismo , COVID-19/imunologia , COVID-19/metabolismo , Fatores de Transcrição Forkhead , Humanos , Índice de Gravidade de Doença , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia
12.
BMC Gastroenterol ; 21(1): 462, 2021 Dec 11.
Artigo em Inglês | MEDLINE | ID: covidwho-1571741

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) is defined as an emerging infectious disease caused by severe acute respiratory syndrome coronavirus 2 and celiac disease (CD) is one of the autoimmune multiorgan diseases, which can be accompanied by an increased risk of viral infections. CD patients, especially untreated subjects, may be at greater risk of infections such as viral illnesses. Interleukin (IL)-6, CD4, CD25, and FOXP3 are known as genes affecting immune homeostasis and relate to the inflammation state. This study aimed to compare the expression levels of aforementioned genes in peripheral blood samples of CD and severe COVID-19 patients. METHODS: Sixty newly diagnosed CD patients with median age (mean ± SD) of 35.40 ± 24.12 years; thirty confirmed severe COVID-19 patients with median age (mean ± SD) of 59.67 ± 17.22, and 60 healthy subjects with median age (mean ± SD) of 35.6 ± 13.02 years; were recruited from March to September 2020. Fresh whole blood samples were collected, total RNA was obtained and cDNA synthesis was carried out. RNA expression levels of IL-6, CD4, CD25, and FOXP3 genes were assessed using real-time quantitative RT-PCR according to the 2-∆∆Ct formula. Statistical analysis was performed using SPSS (V.21) and GraphPad, Prism (V.6). RESULTS: While increased expression of CD4, CD25, and FOXP3 was observed in CD patients compared to the control group (p = 0.02, p = 0.03, and p < 0.0001 respectively) and COVID-19 patients group (p < 0.0001 for all of them), their expression levels in COVID-19 patients decreased compared to controls (p < 0.0001, p = 0.01, p = 0.007, respectively). Increased IL-6 expression was observed in both groups of patients compared to controls (p < 0.0001 for both of them). CONCLUSIONS: Although untreated CD patients may be at greater risk of developing into severe COVID-19 if they are infected by SARS-CoV-2 virus (due to their high expression of IL-6), increased expression of anti-inflammatory markers in these patients may be beneficial for them with the ability of reducing the severity of COVID-19 disease, which needs to be proven in future studies involving celiac patients infected with COVID-19.


Assuntos
COVID-19 , Doença Celíaca , Adolescente , Adulto , Doença Celíaca/genética , Criança , Fatores de Transcrição Forkhead/genética , Homeostase , Humanos , Interleucina-2 , Interleucina-6/genética , Pessoa de Meia-Idade , SARS-CoV-2 , Linfócitos T Reguladores , Adulto Jovem
13.
PLoS Pathog ; 17(12): e1010085, 2021 12.
Artigo em Inglês | MEDLINE | ID: covidwho-1559373

RESUMO

Regulatory T (Treg) cells, which constitute about 5-10% of CD4+T cells expressing Foxp3 transcription factor and CD25(IL-2 receptor α chain), are key regulators in controlling immunological self-tolerance and various immune responses. However, how Treg cells control antigen-specific immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains unclear. In this study, we examined the effect of transient breakdown of the immunological tolerance induced by Treg-cell depletion on adaptive immune responses against administered SARS-CoV-2 antigen, spike protein 1 (S1). Notably, without the use of adjuvants, transient Treg-cell depletion in mice induced anti-S1 antibodies that neutralized authentic SARS-CoV-2, follicular helper T cell formation and S1-binding germinal center B cell responses, but prevented the onset of developing autoimmune diseases. To further clarify the mechanisms, we investigated maturation of dendritic cells (DCs), which is essential to initiate antigen-specific immunity. We found that the transient Treg-cell depletion resulted in maturation of both migratory and resident DCs in draining lymph nodes that captured S1-antigen. Moreover, we observed S1-specific CD4+ T cells and CD8+ T cells with interferon-γ production. Thus, captured S1 was successfully presented by DCs, including cross-presentation to CD8+ T cells. These data indicate that transient Treg-cell depletion in the absence of adjuvants induces maturation of antigen-presenting DCs and succeeds in generating antigen-specific humoral and cellular immunity against emerging SARS-CoV-2 antigens. Finally, we showed that SARS-CoV-2 antigen-specific immune responses induced by transient Treg-cell depletion in the absence of adjuvants were compatible with those induced with an effective adjuvant, polyriboinosinic:polyribocytidyl acid (poly IC) and that the combination of transient Treg-cell depletion with poly IC induced potent responses. These findings highlight the capacity for manipulating Treg cells to induce protective adaptive immunity to SARS-CoV-2 with activating antigen-presenting DCs, which may improve the efficacy of ongoing vaccine therapies and help enhance responses to emerging SARS-CoV-2 variants.


Assuntos
Imunidade Adaptativa/imunologia , Antígenos Virais/imunologia , COVID-19/imunologia , Fatores de Transcrição Forkhead/imunologia , SARS-CoV-2/imunologia , Animais , Apresentação de Antígeno/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , COVID-19/virologia , Chlorocebus aethiops , Células Dendríticas/imunologia , Feminino , Centro Germinativo/imunologia , Humanos , Tolerância Imunológica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos MRL lpr , Linfócitos T Reguladores/imunologia , Células Vero
15.
ACS Infect Dis ; 7(6): 1483-1502, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: covidwho-1387146

RESUMO

Viral proteases are highly specific and recognize conserved cleavage site sequences of ∼6-8 amino acids. Short stretches of homologous host-pathogen sequences (SSHHPS) can be found spanning the viral protease cleavage sites. We hypothesized that these sequences corresponded to specific host protein targets since >40 host proteins have been shown to be cleaved by Group IV viral proteases and one Group VI viral protease. Using PHI-BLAST and the viral protease cleavage site sequences, we searched the human proteome for host targets and analyzed the hit results. Although the polyprotein and host proteins related to the suppression of the innate immune responses may be the primary targets of these viral proteases, we identified other cleavable host proteins. These proteins appear to be related to the virus-induced phenotype associated with Group IV viruses, suggesting that information about viral pathogenesis may be extractable directly from the viral genome sequence. Here we identify sequences cleaved by the SARS-CoV-2 papain-like protease (PLpro) in vitro within human MYH7 and MYH6 (two cardiac myosins linked to several cardiomyopathies), FOXP3 (an X-linked Treg cell transcription factor), ErbB4 (HER4), and vitamin-K-dependent plasma protein S (PROS1), an anticoagulation protein that prevents blood clots. Zinc inhibited the cleavage of these host sequences in vitro. Other patterns emerged from multispecies sequence alignments of the cleavage sites, which may have implications for the selection of animal models and zoonosis. SSHHPS/nsP is an example of a sequence-specific post-translational silencing mechanism.


Assuntos
Papaína , Peptídeo Hidrolases , SARS-CoV-2/enzimologia , Proteases Virais/metabolismo , Sequência de Aminoácidos , Miosinas Cardíacas/química , Fatores de Transcrição Forkhead/química , Humanos , Cadeias Pesadas de Miosina/química , Papaína/metabolismo , Peptídeo Hidrolases/metabolismo , Proteína S/química , Receptor ErbB-4/química
16.
Proc Natl Acad Sci U S A ; 118(37)2021 09 14.
Artigo em Inglês | MEDLINE | ID: covidwho-1373495

RESUMO

The hallmark of severe COVID-19 is an uncontrolled inflammatory response, resulting from poorly understood immunological dysfunction. We hypothesized that perturbations in FoxP3+ T regulatory cells (Treg), key enforcers of immune homeostasis, contribute to COVID-19 pathology. Cytometric and transcriptomic profiling revealed a distinct Treg phenotype in severe COVID-19 patients, with an increase in Treg proportions and intracellular levels of the lineage-defining transcription factor FoxP3, correlating with poor outcomes. These Tregs showed a distinct transcriptional signature, with overexpression of several suppressive effectors, but also proinflammatory molecules like interleukin (IL)-32, and a striking similarity to tumor-infiltrating Tregs that suppress antitumor responses. Most marked during acute severe disease, these traits persisted somewhat in convalescent patients. A screen for candidate agents revealed that IL-6 and IL-18 may individually contribute different facets of these COVID-19-linked perturbations. These results suggest that Tregs may play nefarious roles in COVID-19, by suppressing antiviral T cell responses during the severe phase of the disease, and by a direct proinflammatory role.


Assuntos
COVID-19/etiologia , Linfócitos T Reguladores/fisiologia , Adulto , Idoso , Linfócitos T CD4-Positivos/virologia , Feminino , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Inflamação/metabolismo , Inflamação/virologia , Interleucina-18/genética , Interleucina-18/metabolismo , Subunidade alfa de Receptor de Interleucina-2/genética , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Linfócitos do Interstício Tumoral/fisiologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/virologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
Virology ; 563: 74-81, 2021 11.
Artigo em Inglês | MEDLINE | ID: covidwho-1373295

RESUMO

The levels of messenger RNA (mRNA) transcription of FOXP3, IFN-γ, TNF, IL-6 and COX-2 from both COVID-19 infected and control subjects were evaluated using SYBRTM green real-time polymerase chain reaction (RT-PCR). Severe/critical cases showed significantly lower lymphocyte counts and higher neutrophil counts than the mild or moderate cases. There were significantly lower levels of mRNA expressions of IFN-γ, TNFα and FOXP3 in COVID-19 patients than in the control group. On the other hand, IL-6 and COX-2 expressions were significantly higher in patients suffering from severe disease. FOXP3 expressions were correlated with the severities of hypoxia and were excellent in predicting the disease severity. This was followed by the IL-6, COX-2 and TNFα expressions. FOXP3 expression was the only biomarker to show a significant correlation with patient mortality. It was concluded that SARS-CoV-2 infection is associated with the downregulation of FOXP3 and upregulations of IL-6 and COX-2.


Assuntos
COVID-19/metabolismo , Citocinas/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Hipóxia/metabolismo , RNA Mensageiro/metabolismo , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença
18.
Front Immunol ; 12: 655122, 2021.
Artigo em Inglês | MEDLINE | ID: covidwho-1365539

RESUMO

FOXP3+ regulatory T cells (Tregs) are central for maintaining peripheral tolerance and immune homeostasis. Because of their immunosuppressive characteristics, Tregs are a potential therapeutic target in various diseases such as autoimmunity, transplantation and infectious diseases like COVID-19. Numerous studies are currently exploring the potential of adoptive Treg therapy in different disease settings and novel genome editing techniques like CRISPR/Cas will likely widen possibilities to strengthen its efficacy. However, robust and expeditious protocols for genome editing of human Tregs are limited. Here, we describe a rapid and effective protocol for reaching high genome editing efficiencies in human Tregs without compromising cell integrity, suitable for potential therapeutic applications. By deletion of IL2RA encoding for IL-2 receptor α-chain (CD25) in Tregs, we demonstrated the applicability of the method for downstream functional assays and highlighted the importance for CD25 for in vitro suppressive function of human Tregs. Moreover, deletion of IL6RA (CD126) in human Tregs elicits cytokine unresponsiveness and thus may prevent IL-6-mediated instability of Tregs, making it an attractive target to potentially boost functionality in settings of adoptive Treg therapies to contain overreaching inflammation or autoimmunity. Thus, our rapid and efficient protocol for genome editing in human Tregs may advance possibilities for Treg-based cellular therapies.


Assuntos
Edição de Genes/métodos , Subunidade alfa de Receptor de Interleucina-2/genética , Receptores de Interleucina-6/genética , Linfócitos T Reguladores/metabolismo , Buffy Coat/citologia , Sistemas CRISPR-Cas/genética , Fatores de Transcrição Forkhead/metabolismo , Técnicas de Silenciamento de Genes , Células HEK293 , Voluntários Saudáveis , Humanos , Imunoterapia Adotiva/métodos , Cultura Primária de Células , RNA Guia de Cinetoplastídeos/genética , Fatores de Tempo
19.
Nat Commun ; 12(1): 4354, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: covidwho-1315596

RESUMO

Understanding how SARS-CoV-2 spreads within the respiratory tract is important to define the parameters controlling the severity of COVID-19. Here we examine the functional and structural consequences of SARS-CoV-2 infection in a reconstructed human bronchial epithelium model. SARS-CoV-2 replication causes a transient decrease in epithelial barrier function and disruption of tight junctions, though viral particle crossing remains limited. Rather, SARS-CoV-2 replication leads to a rapid loss of the ciliary layer, characterized at the ultrastructural level by axoneme loss and misorientation of remaining basal bodies. Downregulation of the master regulator of ciliogenesis Foxj1 occurs prior to extensive cilia loss, implicating this transcription factor in the dedifferentiation of ciliated cells. Motile cilia function is compromised by SARS-CoV-2 infection, as measured in a mucociliary clearance assay. Epithelial defense mechanisms, including basal cell mobilization and interferon-lambda induction, ramp up only after the initiation of cilia damage. Analysis of SARS-CoV-2 infection in Syrian hamsters further demonstrates the loss of motile cilia in vivo. This study identifies cilia damage as a pathogenic mechanism that could facilitate SARS-CoV-2 spread to the deeper lung parenchyma.


Assuntos
COVID-19/patologia , Cílios/ultraestrutura , Depuração Mucociliar/fisiologia , SARS-CoV-2 , Animais , Axonema , Corpos Basais , Cílios/metabolismo , Cílios/patologia , Cricetinae , Citocinas , Células Epiteliais/patologia , Fatores de Transcrição Forkhead/metabolismo , Humanos , Pulmão/patologia , Masculino , Mesocricetus , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Replicação Viral
20.
Open Biol ; 11(6): 210069, 2021 06.
Artigo em Inglês | MEDLINE | ID: covidwho-1261130

RESUMO

The COVID-19 pandemic has wreaked unprecedented societal havoc worldwide. The infected individuals may present mild to severe symptoms, with nearly 20% of the confirmed patients impaired with significant complications, including multi-organ failure. Acute respiratory distress imposed by SARS-CoV-2 largely results from an aggravated cytokine storm and deregulated immune response. The forkhead box O (FoxO) transcription factors are reported to play a significant role in maintaining normal cell physiology by regulating survival, apoptosis, oxidative stress, development and maturation of T and B lymphocytes, secretion of inflammatory cytokines, etc. We propose a potent anti-inflammatory approach based on activation of the FoxO as an attractive strategy against the novel coronavirus. This regime will be focused on restoring redox and inflammatory homeostasis along with repair of the damaged tissue, activation of lymphocyte effector and memory cells. Repurposing FoxO activators as a means to alleviate the inflammatory burst following SARS-CoV-2 infection can prove immensely valuable in the ongoing pandemic and provide a reliable groundwork for enriching our repertoire of antiviral modalities for any such complication in the future. Altogether, our review highlights the possible efficacy of FoxO activation as a novel arsenal for clinical management of COVID-19.


Assuntos
COVID-19/metabolismo , COVID-19/virologia , Fatores de Transcrição Forkhead/metabolismo , Interações Hospedeiro-Patógeno , SARS-CoV-2/fisiologia , Biomarcadores , COVID-19/epidemiologia , Citocinas/metabolismo , Gerenciamento Clínico , Suscetibilidade a Doenças , Descoberta de Drogas , Regulação da Expressão Gênica/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Inflamação/tratamento farmacológico , Inflamação/etiologia , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Terapia de Alvo Molecular , Oxirredução , Transdução de Sinais , Tratamento Farmacológico da COVID-19
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