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1.
Cardiovasc Ther ; 2020: 4018478, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042222

RESUMO

Background: Endothelial progenitor cells (EPCs) are recruited to injured endothelium and contribute to its regeneration. There is evidence that moderate ethanol consumption prevents the development and progression of atherosclerosis in a variety of in vitro and in vivo models and increases the mobilization of progenitor cells. Furthermore, there are studies that identified ethanol at low concentration as a therapeutic tool to mobilize progenitor cells in peripheral blood. At the same time, the cell number of EPCs represents a close link to cardiovascular system constitution and function and contributes to cardiovascular risk. The aim of this study was to evaluate the effect of low dose ethanol on typical features of endothelial colony-forming cells (ECFCs), a proliferative subtype of EPCs. Methods and Results: We tested whether ethanol impacts the functional abilities of ECFC (e.g., migration, tube formation, and proliferation) using in vitro assays, the intercommunication of ECFC by exploring cell surface molecules by flow cytometry, and the expression of (anti-)angiogenic molecules by ELISA. Low concentrations of ethanol concentration promoted migration, proliferation, and tubule formation of ECFC. The expression of the cell surface marker VE-cadherin, a protein which plays an important role in cell-cell interaction, was enhanced by ethanol, while (anti-)angiogenic molecule expression was not impacted. Conclusion: Ethanol at moderate concentrations increases the angiogenic abilities of endothelial progenitor cells thus possibly contributing to vasoprotection.


Assuntos
Indutores da Angiogênese/farmacologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Progenitoras Endoteliais/efeitos dos fármacos , Etanol/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Antígenos CD/metabolismo , Caderinas/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Células Progenitoras Endoteliais/metabolismo , Humanos
2.
PLoS One ; 15(10): e0238836, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33095797

RESUMO

Recently, the Cancer Genome Atlas and Asian Cancer Research Group propose two new classifications system of gastric cancer by using multi-platforms of molecular analyses. However, these highly complicated and cost technologies have not yet been translated into full clinical utility. In addition, the clinicians are expected to gain more guidance of treatment for different molecular subtypes. In this study, we developed a panel of gastric cancer patients in population from Southern China using commercially accessible TMA and immunohistochemical technology. A cohort of 259 GC patients was classified into 4 subtypes on the basis of expression of mismatch repair proteins (PMS2, MLH1, MSH2, and MSH6), E-cadherin and p21 protein. We observed that the subtypes presented distinct prognosis. dMMR-like subtype was associated with the best prognosis, and E-cadherin-a subtype was associated with the worst prognosis. Patients with p21-High and p21-Ligh subtypes had intermediate overall survival. In multivariate analysis, the dMMR-like subtype remained an independent prediction power for overall survival in the model. We described a molecular classification of gastric cancers using clinically applicable assay. The biological relevance of the four subtypes was illustrated by significant differences in prognosis. Our molecular classification provided an effective and inexpensive screening tool for improving prognostic models. Nevertheless, our study should be considered preliminary and carries a limited predictive value as a single-center retrospective study.


Assuntos
Proteínas de Neoplasias/metabolismo , Neoplasias Gástricas/classificação , Neoplasias Gástricas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/metabolismo , Biomarcadores Tumorais/metabolismo , Caderinas/metabolismo , China , Estudos de Coortes , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Reparo de Erro de Pareamento de DNA , Proteínas de Ligação a DNA/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Endonuclease PMS2 de Reparo de Erro de Pareamento/metabolismo , Proteína 1 Homóloga a MutL/metabolismo , Proteína 2 Homóloga a MutS/metabolismo , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Análise Serial de Tecidos
3.
Nat Commun ; 11(1): 5091, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-33037195

RESUMO

Sialic acid-binding immunoglobulin-type lectins (Siglecs) are immunomodulatory receptors that are regulated by their glycan ligands. The connections between Siglecs and human disease motivate improved methods to detect Siglec ligands. Here, we describe a new versatile set of Siglec-Fc proteins for glycan ligand detection. Enhanced sensitivity and selectivity are enabled through multimerization and avoiding Fc receptors, respectively. Using these Siglec-Fc proteins, Siglec ligands are systematically profiled on healthy and cancerous cells and tissues, revealing many unique patterns. Additional features enable the production of small, homogenous Siglec fragments and development of a quantitative ligand-binding mass spectrometry assay. Using this assay, the ligand specificities of several Siglecs are clarified. For CD33 (Siglec-3), we demonstrate that it recognizes both α2-3 and α2-6 sialosides in solution and on cells, which has implications for its link to Alzheimer's disease susceptibility. These soluble Siglecs reveal the abundance of their glycan ligands on host cells as self-associated molecular patterns.


Assuntos
Polissacarídeos/análise , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/química , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/metabolismo , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Neoplasias da Mama/metabolismo , Células CHO , Cricetulus , Feminino , Células HEK293 , Humanos , Fragmentos Fc das Imunoglobulinas/genética , Fragmentos Fc das Imunoglobulinas/metabolismo , Imunoglobulina G/genética , Imunoglobulina G/metabolismo , Células K562 , Espectrometria de Massas , Polissacarídeos/metabolismo , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/genética , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/isolamento & purificação , Ácidos Siálicos/metabolismo , Sialiltransferases/genética , Sialiltransferases/metabolismo , Baço/citologia , Baço/metabolismo , Estreptavidina/metabolismo
4.
mBio ; 11(5)2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948688

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection induces a T cell response that most likely contributes to virus control in COVID-19 patients but may also induce immunopathology. Until now, the cytotoxic T cell response has not been very well characterized in COVID-19 patients. Here, we analyzed the differentiation and cytotoxic profile of T cells in 30 cases of mild COVID-19 during acute infection. SARS-CoV-2 infection induced a cytotoxic response of CD8+ T cells, but not CD4+ T cells, characterized by the simultaneous production of granzyme A and B as well as perforin within different effector CD8+ T cell subsets. PD-1-expressing CD8+ T cells also produced cytotoxic molecules during acute infection, indicating that they were not functionally exhausted. However, in COVID-19 patients over the age of 80 years, the cytotoxic T cell potential was diminished, especially in effector memory and terminally differentiated effector CD8+ cells, showing that elderly patients have impaired cellular immunity against SARS-CoV-2. Our data provide valuable information about T cell responses in COVID-19 patients that may also have important implications for vaccine development.IMPORTANCE Cytotoxic T cells are responsible for the elimination of infected cells and are key players in the control of viruses. CD8+ T cells with an effector phenotype express cytotoxic molecules and are able to perform target cell killing. COVID-19 patients with a mild disease course were analyzed for the differentiation status and cytotoxic profile of CD8+ T cells. SARS-CoV-2 infection induced a vigorous cytotoxic CD8+ T cell response. However, this cytotoxic profile of T cells was not detected in COVID-19 patients over the age of 80 years. Thus, the absence of a cytotoxic response in elderly patients might be a possible reason for the more frequent severity of COVID-19 in this age group than in younger patients.


Assuntos
Linfócitos T CD8-Positivos/patologia , Infecções por Coronavirus/imunologia , Pneumonia Viral/imunologia , Linfócitos T Citotóxicos/patologia , Idoso de 80 Anos ou mais , Antígenos CD/metabolismo , Betacoronavirus/patogenicidade , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Citotoxinas/metabolismo , Feminino , Humanos , Imunidade Celular , Masculino , Pessoa de Meia-Idade , Pandemias , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/patologia , Linfócitos T Citotóxicos/imunologia
5.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 36(8): 680-686, 2020 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32958123

RESUMO

Objective To investigate the role of butyrophilin 3A1 (BTN3A1) in the activation and proliferation of human peripheral blood Vγ9Vδ2 T cells induced by M. tuberculosis heat resistant antigen (MTB-HAg). Methods Human peripheral blood mononuclear cells (PBMCs) were treated with BTN3A1 blocking antibody for 3 hours and then stimulated with MTB-HAg or phosphoantigen (PAg). At 24 hours of stimulation, the cells were collected to detect the expression of CD69 in Vγ9Vδ2 T cells by flow cytometry. At 20 hours of stimulation, the cells were collected to detect the proportions of cells producing helper T cell type I (Th1) cytokines IFN-γ and tumor necrosis factor α (TNF-α) in the Vγ9Vδ2 T cells. The PBMCs were also stimulated and cultured in IL-2-containing medium for 10 days, and the expansion and proliferation activity of Vγ9Vδ2 T cells were detected. Results After stimulated with MTB-HAg, the average fluorescence intensity of CD69 and the proportion of CD69 positive cells in Vγ9Vδ2 T cells decreased significantly in BTN3A1 blocked group, being 13.84% and 43.00% of those in the stimulated group, respectively. However, the average fluorescence intensity of CD69 molecules and the proportion of positive cells in PAg blocked group were significantly inhibited (3.10%, 4.47% and 9.53%, 10.91% of those in the stimulated group). The proportions of IFN-γ and TNF-α producing Vγ9Vδ2 T cells stimulated with MTB-HAg decreased significantly in the BTN3A1 blocked group, and the expansion number and cell proliferation activity of Vγ9Vδ2 T cells were also reduced significantly in the BTN3A1 blocked group. The results were similar to those of the PAg blocked group. Conclusion BTN3A1 promotes activation and proliferation of peripheral blood Vγ9Vδ2 T cells induced by MTB-HAg.


Assuntos
Antígenos de Bactérias , Antígenos CD , Butirofilinas , Ativação Linfocitária , Linfócitos T , Antígenos de Bactérias/imunologia , Antígenos CD/genética , Antígenos CD/metabolismo , Butirofilinas/genética , Butirofilinas/metabolismo , Proliferação de Células/genética , Humanos , Ativação Linfocitária/genética , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia
6.
Nat Commun ; 11(1): 4660, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938908

RESUMO

Intratumor spatial heterogeneity facilitates therapeutic resistance in glioblastoma (GBM). Nonetheless, understanding of GBM heterogeneity is largely limited to the surgically resectable tumor core lesion while the seeds for recurrence reside in the unresectable tumor edge. In this study, stratification of GBM to core and edge demonstrates clinically relevant surgical sequelae. We establish regionally derived models of GBM edge and core that retain their spatial identity in a cell autonomous manner. Upon xenotransplantation, edge-derived cells show a higher capacity for infiltrative growth, while core cells demonstrate core lesions with greater therapy resistance. Investigation of intercellular signaling between these two tumor populations uncovers the paracrine crosstalk from tumor core that promotes malignancy and therapy resistance of edge cells. These phenotypic alterations are initiated by HDAC1 in GBM core cells which subsequently affect edge cells by secreting the soluble form of CD109 protein. Our data reveal the role of intracellular communication between regionally different populations of GBM cells in tumor recurrence.


Assuntos
Antígenos CD/metabolismo , Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Histona Desacetilase 1/metabolismo , Proteínas de Neoplasias/metabolismo , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Feminino , Proteínas Ligadas por GPI/metabolismo , Regulação Neoplásica da Expressão Gênica , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/mortalidade , Histona Desacetilase 1/antagonistas & inibidores , Histona Desacetilase 1/genética , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Humanos , Camundongos SCID , Fenilbutiratos/farmacologia , Transdução de Sinais , Microambiente Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
7.
PLoS One ; 15(9): e0239284, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32941503

RESUMO

The Rho GTPase RAC1 is an important regulator of cytoskeletal dynamics, but the role of macrophage-specific RAC1 has not been explored during atherogenesis. We analyzed RAC1 expression in human carotid atherosclerotic plaques using immunofluorescence and found higher macrophage RAC1 expression in advanced plaques compared with intermediate human atherosclerotic plaques. We then produced mice with Rac1-deficient macrophages by breeding conditional floxed Rac1 mice (Rac1fl/fl) with mice expressing Cre from the macrophage-specific lysosome M promoter (LC). Atherosclerosis was studied in vivo by infecting Rac1fl/fl and Rac1fl/fl/LC mice with AdPCSK9 (adenoviral vector overexpressing proprotein convertase subtilisin/kexin type 9). Rac1fl/fl/LC macrophages secreted lower levels of IL-6 and TNF-α and exhibited reduced foam cell formation and lipid uptake. The deficiency of Rac1 in macrophages reduced the size of aortic atherosclerotic plaques in AdPCSK9-infected Rac1fl/fl/LC mice. Compare with controls, intima/media ratios, the size of necrotic cores, and numbers of CD68-positive macrophages in atherosclerotic plaques were reduced in Rac1-deficient mice. Moreover, we found that RAC1 interacts with actin-binding filamin A. Macrophages expressed increased RAC1 levels in advanced human atherosclerosis. Genetic inactivation of RAC1 impaired macrophage function and reduced atherosclerosis in mice, suggesting that drugs targeting RAC1 may be useful in the treatment of atherosclerosis.


Assuntos
Aterosclerose/metabolismo , Macrófagos/metabolismo , Neuropeptídeos/genética , Proteínas rac1 de Ligação ao GTP/genética , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/genética , Antígenos de Diferenciação Mielomonocítica/metabolismo , Aterosclerose/genética , Aterosclerose/patologia , Células Cultivadas , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Metabolismo dos Lipídeos , Camundongos , Camundongos Endogâmicos C57BL , Neuropeptídeos/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo
8.
Front Immunol ; 11: 1870, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983106

RESUMO

Coronavirus disease 2019 (COVID-19) which is caused by the novel SARS-CoV-2 virus is a severe flu-like illness which is associated with hyperinflammation and immune dysfunction. The virus induces a strong T and B cell response but little is known about the immune pathology of this viral infection. Acute Plasmodium falciparum malaria also causes acute clinical illness and is characterized by hyperinflammation due to the strong production of pro-inflammatory cytokines and a massive activation of T cells. In malaria, T cells express a variety of co-inhibitory receptors which might be a consequence of their activation but also might limit their overwhelming function. Thus, T cells are implicated in protection as well as in pathology. The outcome of malaria is thought to be a consequence of the balance between co-activation and co-inhibition of T cells. Following the hypothesis that T cells in COVID-19 might have a similar, dual function, we comprehensively characterized the differentiation (CCR7, CD45RO) and activation status (HLA-DR, CD38, CD69, CD226), the co-expression of co-inhibitory molecules (PD1, TIM-3, LAG-3, BTLA, TIGIT), as well as the expression pattern of the transcription factors T-bet and eomes of CD8+ and CD4+ T cells of PBMC of n = 20 SARS-CoV-2 patients compared to n = 10 P. falciparum infected patients and n = 13 healthy controls. Overall, acute COVID-19 and malaria infection resulted in a comparably elevated activation and altered differentiation status of the CD8+ and CD4+ T cell populations. T effector cells of COVID-19 and malaria patients showed higher frequencies of the inhibitory receptors T-cell immunoglobulin mucin-3 (TIM-3) and Lymphocyte-activation gene-3 (LAG-3) which was linked to increased activation levels and an upregulation of the transcription factors T-bet and eomes. COVID-19 patients with a more severe disease course showed higher levels of LAG-3 and TIM-3 than patients with a mild disease course. During recovery, a rapid normalization of these inhibitory receptors could be observed. In summary, comparing the expression of different co-inhibitory molecules in CD8+ and CD4+ T cells in COVID-19 vs. malaria, there is a transient increase of the expression of certain inhibitory receptors like LAG-3 and TIM-3 in COVID-19 in the overall context of acute immune activation.


Assuntos
Antígenos CD/metabolismo , Betacoronavirus/genética , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por Coronavirus/imunologia , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Ativação Linfocitária/imunologia , Malária Falciparum/imunologia , Plasmodium falciparum/isolamento & purificação , Pneumonia Viral/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Doença Aguda , Adulto , Idoso , Células Cultivadas , Estudos de Coortes , Infecções por Coronavirus/virologia , Feminino , Humanos , Malária Falciparum/parasitologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/virologia , Receptor de Morte Celular Programada 1/metabolismo , Índice de Gravidade de Doença
9.
Life Sci ; 259: 118389, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32898522

RESUMO

AIMS: Adenosine triphosphate (ATP) is released at a high concentration in the tumor microenvironment. The overexpression of ectonucleotidases in non-small-cell lung cancer (NSCLC), metabolizing ΑΤP to the immunosuppressive adenosine, is studied. MATERIALS AND METHODS: We examined the expression of the ectonucleotidases CD73 and CD39 in NSCLC in parallel with immunological parameters and markers of hypoxia and anaerobic metabolism. In vitro experiments with A549 and H1299 lung cancer cell lines were also conducted. RESULTS: CD73 and CD39 were not expressed by normal bronchial and alveolar epithelium. In contrast, these were overexpressed by cancer cells, cancer-associated fibroblasts (CAFs), and tumor-infiltrating lymphocytes (TILs). High CD73 cancer cell expression was directly linked with lactate dehydrogenase LDH5 and with hypoxia-inducible factor HIF1α expression by cancer cells. The expression of CD39 by CAFs was directly linked with PD-L1 expression by cancer cells. A significant abundance of FOXP3+ and PD-1+ TILs was noted in tumors with high CD73 and CD39 stroma expression. In in vitro experiments, hypoxia and acidity induced CD73 mRNA and protein levels in cancer cell lines. Exposure of cancer cell lines to adenosine induced the expression of PD-L1 and LDHA mRNA and protein levels. CONCLUSION: Ectonucleotidases are up-regulated in cancer cells, CAFs, and TILs in lung tumors. Such overexpression is linked with regulatory TIL-phenotype and PD-L1 up-regulation by cancer cells. Overexpression of LDH5 is up-regulated by adenosine, creating a vicious cycle, as the high amounts of ATP produced by LDH5-mediated anaerobic glycolysis promote the production of adenosine by a tumor microenvironment rich in ectonucleotidases.


Assuntos
5'-Nucleotidase/metabolismo , Antígenos CD/metabolismo , Apirase/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Hipóxia/etiologia , Neoplasias Pulmonares/metabolismo , Adenosina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígeno B7-H1/metabolismo , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Hipóxia/metabolismo , Tolerância Imunológica , Neoplasias Pulmonares/enzimologia , Masculino , Pessoa de Meia-Idade
10.
Sci Immunol ; 5(51)2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32989174

RESUMO

Severe COVID-19 is characterized by excessive inflammation of the lower airways. The balance of protective versus pathological immune responses in COVID-19 is incompletely understood. Mucosa-associated invariant T (MAIT) cells are antimicrobial T cells that recognize bacterial metabolites, and can also function as innate-like sensors and mediators of antiviral responses. Here, we investigated the MAIT cell compartment in COVID-19 patients with moderate and severe disease, as well as in convalescence. We show profound and preferential decline in MAIT cells in the circulation of patients with active disease paired with strong activation. Furthermore, transcriptomic analyses indicated significant MAIT cell enrichment and pro-inflammatory IL-17A bias in the airways. Unsupervised analysis identified MAIT cell CD69high and CXCR3low immunotypes associated with poor clinical outcome. MAIT cell levels normalized in the convalescent phase, consistent with dynamic recruitment to the tissues and later release back into the circulation when disease is resolved. These findings indicate that MAIT cells are engaged in the immune response against SARS-CoV-2 and suggest their possible involvement in COVID-19 immunopathogenesis.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/patologia , Células T Invariáveis Associadas à Mucosa/imunologia , Pneumonia Viral/patologia , Adulto , Idoso , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Infecções por Coronavirus/imunologia , Feminino , Humanos , Imunidade Inata/imunologia , Inflamação/imunologia , Interleucina-17/metabolismo , Lectinas Tipo C/metabolismo , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/imunologia , Receptores CXCR3/metabolismo , Adulto Jovem
11.
PLoS One ; 15(8): e0225420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764749

RESUMO

The H196 residue in SIVmac239 Nef is conserved across the majority of HIV and SIV isolates, lies immediately adjacent to the AP-2 (adaptor protein 2) binding di-leucine domain (ExxxLM195), and is critical for several described AP-2 dependent Nef functions, including the downregulation of tetherin (BST-2/CD317), CD4, and others. Surprisingly, many stocks of the closely related SIVmac251 swarm virus harbor a nef allele encoding a Q196. In SIVmac239, this variant is associated with loss of multiple AP-2 dependent functions. Publicly available sequences for SIVmac251 stocks were mined for variants linked to Q196 that might compensate for functional defects associated with this residue. Variants were engineered into the SIVmac239 backbone and in Nef expression plasmids and flow cytometry was used to examine surface tetherin expression in primary CD4 T cells and surface CD4 expression in SupT1 cells engineered to express rhesus CD4. We found that SIVmac251 stocks that encode a Q196 residue in Nef uniformly also encode an upstream R191 residue. We show that R191 restores the ability of Nef to downregulate tetherin in the presence of Q196 and has a similar but less pronounced impact on CD4 expression. However, a published report showed Q196 commonly evolves to H196 in vivo, suggesting a fitness cost. R191 may represent compensatory evolution to restore the ability to downregulate tetherin lost in viruses harboring Q196.


Assuntos
Antígeno 2 do Estroma da Médula Óssea/metabolismo , Vírus da Imunodeficiência Símia/genética , Proteínas Virais Reguladoras e Acessórias/genética , Animais , Antígenos CD/metabolismo , Antígeno 2 do Estroma da Médula Óssea/genética , Linfócitos T CD4-Positivos/metabolismo , Proteínas Ligadas por GPI/metabolismo , Produtos do Gene nef/metabolismo , Macaca mulatta/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/metabolismo , Vírus da Imunodeficiência Símia/fisiologia , Proteínas Virais Reguladoras e Acessórias/metabolismo
12.
Nat Immunol ; 21(9): 1107-1118, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32788748

RESUMO

In coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the relationship between disease severity and the host immune response is not fully understood. Here we performed single-cell RNA sequencing in peripheral blood samples of 5 healthy donors and 13 patients with COVID-19, including moderate, severe and convalescent cases. Through determining the transcriptional profiles of immune cells, coupled with assembled T cell receptor and B cell receptor sequences, we analyzed the functional properties of immune cells. Most cell types in patients with COVID-19 showed a strong interferon-α response and an overall acute inflammatory response. Moreover, intensive expansion of highly cytotoxic effector T cell subsets, such as CD4+ effector-GNLY (granulysin), CD8+ effector-GNLY and NKT CD160, was associated with convalescence in moderate patients. In severe patients, the immune landscape featured a deranged interferon response, profound immune exhaustion with skewed T cell receptor repertoire and broad T cell expansion. These findings illustrate the dynamic nature of immune responses during disease progression.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Interferon Tipo I/metabolismo , Pneumonia Viral/imunologia , Receptores Imunológicos/metabolismo , Adolescente , Adulto , Idoso , Antígenos CD/genética , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Estudos de Coortes , Infecções por Coronavirus/sangue , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Feminino , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/imunologia , Proteínas Ligadas por GPI/metabolismo , Humanos , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , RNA-Seq , Receptores Imunológicos/genética , Receptores Imunológicos/imunologia , Índice de Gravidade de Doença , Análise de Célula Única
13.
BMC Infect Dis ; 20(1): 590, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778058

RESUMO

BACKGROUND: Antiviral therapy is recommended for patients with immune-active chronic hepatitis B (CHB) to decrease the risk of liver-related complications. However, the outcomes of the pegylated IFN-α (PEG-IFN-α) therapy vary among CHB patients. We aimed to identify factors that can influence the outcomes in CHB patients who received antiviral PEG-IFN-α monotherapy. METHODS: Thirty-two CHB patients who received PEG-IFN-α monotherapy were enrolled in this study. All of the patients underwent two liver biopsies at baseline and 6 months after the initiation of the therapy. CD8+ T cells, CD4+ T cells, CD68+ mononuclear cells, and PD-1 levels in the 64 liver biopsy specimens were examined via immunofluorescence. RESULTS: The overall median frequency of CD8+ T cells in the liver tissues of 32 CHB patients significantly decreased at 6 months after the therapy initiation (p < 0.01). In the FIER (fibrosis and inflammation response with HBeAg seroconversion) group, CD8+PD-1+ T cells significantly decreased at 6 months (p < 0.05), while CD8+PD-1- T cells had no significant difference. On the contrary, in the FIENR (no fibrosis and inflammation response and HBeAg seroconversion) group, CD8+PD-1- T cells significantly decreased after 6 months of PEG-IFN-α treatment (p < 0.05), while CD8+PD-1+ T cells had no significant difference. In addition, the levels of CD68+ mononuclear cells in the FIER group showed an overall increasing trend after treatment (p < 0.05). CONCLUSIONS: The changes in the levels of CD8+PD-1+ T cells and CD68+ mononuclear cells may be related to the response to PEG-IFN-α therapy.


Assuntos
Antivirais/uso terapêutico , Linfócitos T CD8-Positivos/metabolismo , Hepatite B Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Fígado/patologia , Polietilenoglicóis/uso terapêutico , Adulto , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Antígenos E da Hepatite B/sangue , Antígenos E da Hepatite B/imunologia , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Fígado/metabolismo , Masculino , Receptor de Morte Celular Programada 1/metabolismo , Proteínas Recombinantes/uso terapêutico , Adulto Jovem
15.
Free Radic Res ; 54(7): 540-555, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32842802

RESUMO

Radiotherapy is an important treatment regime for lung cancer, worldwide. However, radiation-induced pneumonitis and fibrosis are the treatment-limiting toxicities among patients who have undergone radiotherapy. The epithelial cells via epithelial to mesenchymal transition [EMT] acquires mesenchymal phenotype, which ultimately leads to fibrosis. Many investigations are focussed on understanding the signalling pathways mediating in EMT, however, the role of histone methylation is less understood in radiation-induced lung EMT. In the present study, we analysed the effect of vanillin, an antioxidant, on histone methylation during radiation-induced EMT. The thoracic region of Wistar rats was irradiated with a fractionated dose of X-ray (3 Gy/day) for two weeks (total of 30 Gy). The irradiated animals were sacrificed at the 8th and 16th weeks and tissues were used for analyses. Our data showed that radiation decreased the level of antioxidant enzymes such as SOD, catalase and reduced glutathione that would ultimately enhance oxidative stress in the tissues. Histopathological analysis revealed that radiation increased the infiltration of inflammatory cells to the tissue injury site. Total global histone methylation was increased upon irradiation, which was effectively prevented by vanillin administration. Vanillin enhanced E-cadherin expression and decreased the mesenchymal markers N-cadherin and vimentin in the irradiated lung tissue. The ChIP-qPCR analysis suggested that snail expression in the nucleus might involve in the enrichment of suppressive marker H3K9me3 on the E-cadherin promoter. Finally, we suggested that vanillin administration decreased radiation-induced oxidative stress and EMT expression. Additionally, irradiation increased the H3K9 methylation status with nuclear translocation of snail during lung EMT.


Assuntos
Antígenos CD/metabolismo , Benzaldeídos/metabolismo , Caderinas/metabolismo , Histonas/metabolismo , Pulmão/efeitos da radiação , Células A549 , Animais , Antígenos CD/genética , Caderinas/genética , Transição Epitelial-Mesenquimal , Feminino , Humanos , Pulmão/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/radioterapia , Metilação/efeitos da radiação , Estresse Oxidativo/efeitos da radiação , Regiões Promotoras Genéticas , Ratos , Ratos Wistar
16.
Life Sci ; 259: 118273, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32800831

RESUMO

AIMS: To explore the mechanisms of erythropoietin (EPO)'s protection on inner blood-retinal barrier (iBRB) in experimental diabetic retinopathy. MATERIAL AND METHODS: Male SD rats were rendered diabetic with streptozotocin, followed by intravitreal injection of EPO. The permeability of iBRB was examined with fluorescein isothiocyanate (FITC)-dextran. Human retinal microvascular endothelial cells (HRMECs) and human umbilical vein endothelial cells (HUVECs) were treated with glyoxal and studied for cell viability and barrier function. The expressions of vascular endothelial (VE)-cadherin, Src kinase, vascular endothelial growth factor (VEGF) and VEGF receptor-2 (VEGFR2) were analyzed with Western blot, ELISA, qPCR, or immunofluorescence. KEY FINDINGS: VE-cadherin in rat retinas was down-regulated with diabetes progression. EPO treatment could increase VE-cadherin expression at week 8 and week 16. The expressions of p-Src and p-VE-cadherin were increased at week 2, while decreased at week 8 of diabetes; which were prevented by EPO. The leakage of FITC-dextran in 8-week diabetic rat retinas was ameliorated by EPO. In vitro results showed the expressions of VEGF, p-Src and p-VE-cadherin were increased significantly, accompanied with the decreased barrier function, which were prevented by EPO. Ranibizumab and CGP77675 also inhibited the glyoxal-induced phosphorylation of Src and VE-cadherin. Cellular fractionation showed EPO mitigated the VE-cadherin internalization in glyoxal-treated cells. SIGNIFICANCE: EPO maintained the expression of VE-cadherin in experimental diabetic retinopathy by inhibiting its phosphorylation and internalization through VEGF/VEGFR2/Src pathway, thus improved the integrity of iBRB.


Assuntos
Antígenos CD/biossíntese , Barreira Hematorretiniana/metabolismo , Caderinas/biossíntese , Retinopatia Diabética/metabolismo , Eritropoetina/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Quinases da Família src/metabolismo , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Barreira Hematorretiniana/efeitos dos fármacos , Barreira Hematorretiniana/patologia , Caderinas/genética , Caderinas/metabolismo , Permeabilidade Capilar/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/patologia , Regulação para Baixo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Vasos Retinianos/efeitos dos fármacos , Vasos Retinianos/metabolismo , Vasos Retinianos/patologia
17.
Mol Carcinog ; 59(10): 1174-1187, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32805084

RESUMO

Long noncoding RNAs (LncRNAs) have emerged as important players in cancer biology. Increasing evidence suggests that LncRNAs are frequently dysregulated in cancer and may function as oncogenes or tumor suppressors. Urothelial carcinoma associated 1 (UCA1), a LncRNA, firstly identified in bladder transitional cell carcinoma, seems to act as an oncogene in many different types of human cancers by promoting cell proliferation and migration. In this study, we revealed a novel biological function of UCA1, which was different from that reported by previous studies, was responsible for maintaining the low-tumorigenic, nonmetastatic phenotypes in primary prostate epithelial cells. UCA1 could stabilize E-cadherin protein by preventing the interaction between E-cadherin and its E3 ligase MDM2, which suppressed MDM2-mediated ubiquitination and degradation of E-cadherin. In addition, we also found that UCA1 acted as a sponge of miR-296-3p, which targeted E-cadherin gene CDH1 messenger RNA at the posttranscription level. Taken together, these findings demonstrated that UCA1 had a new important role in effectively keeping E-cadherin at a high level through a dual mechanism, which maintained primary prostate cancer cells at the low-tumorigenic and nonmetastatic status.


Assuntos
Antígenos CD/metabolismo , Biomarcadores Tumorais/metabolismo , Caderinas/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias da Próstata/patologia , RNA Longo não Codificante/genética , Animais , Antígenos CD/genética , Apoptose , Biomarcadores Tumorais/genética , Caderinas/genética , Proliferação de Células , Humanos , Masculino , Camundongos , Camundongos SCID , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Int J Nanomedicine ; 15: 4151-4169, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606670

RESUMO

Purpose: Focused ultrasound (FUS) is a noninvasive method to produce thermal and mechanical destruction along with an immune-stimulatory effect against cancer. However, FUS ablation alone appears insufficient to generate consistent antitumor immunity. In this study, a multifunctional nanoparticle was designed to boost FUS-induced immune effects and achieve systemic, long-lasting antitumor immunity, along with imaging and thermal enhancement. Materials and Methods: PEGylated PLGA nanoparticles encapsulating astragalus polysaccharides (APS) and gold nanorods (AuNRs) were constructed by a simple double emulsion method, characterized, and tested for cytotoxicity. The abilities of PA imaging and thermal-synergetic ablation efficiency were analyzed in vitro and in vivo. The immune-synergistic effect on dendritic cell (DC) differentiation in vitro and the immune response in vivo were also evaluated. Results: The obtained APS/AuNR/PLGA-PEG nanoparticles have an average diameter of 255.00±0.1717 nm and an APS-loading efficiency of 54.89±2.07%, demonstrating their PA imaging capability and high biocompatibility both in vitro and in vivo. In addition, the as-prepared nanoparticles achieved a higher necrosis cell rate and induced apoptosis rate in an in vitro cell suspension assay, greater necrosis area and decreased energy efficiency factor (EEF) in an in vivo rabbit liver assay, and remarkable thermal-synergic performance. In particular, the nanoparticles upregulated the expression of MHC-II, CD80 and CD86 on cocultured DCs in vitro, followed by declining phagocytic function and enhanced interleukin (IL)-12 and interferon (INF)-γ production. Furthermore, they boosted the production of tumor necrosis factor (TNF)-α, IFN-γ, IL-4, IL-10, and IgG1 (P< 0.001) but not IgG2a. Immune promotion peaked on day 3 after FUS in vivo. Conclusion: The multifunctional APS/AuNR/PLGA-PEG nanoparticles can serve as an excellent synergistic agent for FUS therapy, facilitating real-time imaging, promoting thermal ablation effects, and boosting FUS-induced immune effects, which have the potential to be used for further clinical FUS treatment.


Assuntos
Astrágalo (Planta)/química , Neoplasias da Mama/terapia , Ouro/química , Nanopartículas Multifuncionais/química , Nanotubos/química , Polissacarídeos/química , Terapia por Ultrassom , Animais , Antígenos CD/metabolismo , Apoptose , Morte Celular , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Citocinas/metabolismo , Células Dendríticas/citologia , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Imunoglobulina G/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Camundongos Endogâmicos BALB C , Fagocitose , Técnicas Fotoacústicas , Poliésteres/síntese química , Poliésteres/química , Polietilenoglicóis/síntese química , Polietilenoglicóis/química , Coelhos , Nanomedicina Teranóstica , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
Immunol Med ; 43(4): 161-170, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32649844

RESUMO

Cow milk is a nourishing food containing numerous essential nutrients. In Japan, the consumption of cow milk is thought to enhance resistance to exhaustion-related diseases. Although several nutrients in cow milk, such as lactoferrin, are thought to modulate immune cells, the mechanisms remain unclear. Recently, the immunoregulatory functions of food-derived microRNAs or exosomes have been reported. Therefore, we studied the effects of exosomes derived from cow milk (CM-Exs) on immune cells in the present study. We obtained blood samples from healthy adult donors with the approval of the ethics committee. Peripheral blood mononuclear cells (PBMCs) were stimulated with CM-Exs in the absence or presence of interleukin-2 (IL-2) and IL-12. Cell surface markers and intracellular cytokine production were analysed by flow cytometry. CM-Ex stimulation enhanced the expression of CD69 on NK cells. Although CM-Ex stimulation alone did not induce interferon-γ (IFN-γ) production by NK cells or γδT cells, simultaneous stimulation with CM-Ex, IL-2 and IL-12 significantly enhanced IFN-γ production. In conclusion, cow milk consumption alone may not activate immune cells; however, CM-Exs could enhance immune cells under inflammatory conditions.


Assuntos
Exossomos/imunologia , Exossomos/fisiologia , Células Matadoras Naturais/imunologia , Leucócitos Mononucleares/imunologia , Ativação Linfocitária , Leite/citologia , Linfócitos T/imunologia , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Células Cultivadas , Citocinas/metabolismo , Citometria de Fluxo , Humanos , Interferon gama/metabolismo , Interleucina-12/imunologia , Interleucina-2/imunologia , Células Matadoras Naturais/metabolismo , Lectinas Tipo C/metabolismo , Leucócitos Mononucleares/metabolismo , Linfócitos T/metabolismo
20.
Nature ; 584(7820): 291-297, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32728216

RESUMO

The majority of therapies that target individual proteins rely on specific activity-modulating interactions with the target protein-for example, enzyme inhibition or ligand blocking. However, several major classes of therapeutically relevant proteins have unknown or inaccessible activity profiles and so cannot be targeted by such strategies. Protein-degradation platforms such as proteolysis-targeting chimaeras (PROTACs)1,2 and others (for example, dTAGs3, Trim-Away4, chaperone-mediated autophagy targeting5 and SNIPERs6) have been developed for proteins that are typically difficult to target; however, these methods involve the manipulation of intracellular protein degradation machinery and are therefore fundamentally limited to proteins that contain cytosolic domains to which ligands can bind and recruit the requisite cellular components. Extracellular and membrane-associated proteins-the products of 40% of all protein-encoding genes7-are key agents in cancer, ageing-related diseases and autoimmune disorders8, and so a general strategy to selectively degrade these proteins has the potential to improve human health. Here we establish the targeted degradation of extracellular and membrane-associated proteins using conjugates that bind both a cell-surface lysosome-shuttling receptor and the extracellular domain of a target protein. These initial lysosome-targeting chimaeras, which we term LYTACs, consist of a small molecule or antibody fused to chemically synthesized glycopeptide ligands that are agonists of the cation-independent mannose-6-phosphate receptor (CI-M6PR). We use LYTACs to develop a CRISPR interference screen that reveals the biochemical pathway for CI-M6PR-mediated cargo internalization in cell lines, and uncover the exocyst complex as a previously unidentified-but essential-component of this pathway. We demonstrate the scope of this platform through the degradation of therapeutically relevant proteins, including apolipoprotein E4, epidermal growth factor receptor, CD71 and programmed death-ligand 1. Our results establish a modular strategy for directing secreted and membrane proteins for lysosomal degradation, with broad implications for biochemical research and for therapeutics.


Assuntos
Espaço Extracelular/metabolismo , Lisossomos/metabolismo , Proteínas de Membrana/metabolismo , Proteólise , Proteínas Recombinantes de Fusão/metabolismo , Animais , Anticorpos/química , Anticorpos/metabolismo , Antígenos CD/metabolismo , Apolipoproteína E4/metabolismo , Antígeno B7-H1/metabolismo , Sistemas CRISPR-Cas , Linhagem Celular , Receptores ErbB/metabolismo , Feminino , Glicopeptídeos/síntese química , Glicopeptídeos/metabolismo , Humanos , Ligantes , Proteínas de Membrana/química , Camundongos , Domínios Proteicos , Transporte Proteico , Receptor IGF Tipo 2/metabolismo , Receptores da Transferrina/metabolismo , Proteínas Recombinantes de Fusão/síntese química , Proteínas Recombinantes de Fusão/química , Solubilidade , Especificidade por Substrato
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