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1.
Nat Commun ; 11(1): 5077, 2020 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033240

RESUMO

Although substantial progress has been made in cancer biology and treatment, clinical outcomes of bladder carcinoma (BC) patients are still not satisfactory. The tumor microenvironment (TME) is a potential target. Here, by single-cell RNA sequencing on 8 BC tumor samples and 3 para tumor samples, we identify 19 different cell types in the BC microenvironment, indicating high intra-tumoral heterogeneity. We find that tumor cells down regulated MHC-II molecules, suggesting that the downregulated immunogenicity of cancer cells may contribute to the formation of an immunosuppressive microenvironment. We also find that monocytes undergo M2 polarization in the tumor region and differentiate. Furthermore, the LAMP3 + DC subgroup may be able to recruit regulatory T cells, potentially taking part in the formation of an immunosuppressive TME. Through correlation analysis using public datasets containing over 3000 BC samples, we identify a role for inflammatory cancer-associated fibroblasts (iCAFs) in tumor progression, which is significantly related to poor prognosis. Additionally, we characterize a regulatory network depending on iCAFs. These results could help elucidate the protumor mechanisms of iCAFs. Our results provide deep insight into cancer immunology and provide an essential resource for drug discovery in the future.


Assuntos
Fibroblastos/patologia , Inflamação/patologia , Análise de Sequência de RNA , Análise de Célula Única , Bexiga Urinária/patologia , Área Sob a Curva , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Linhagem Celular Tumoral , Polaridade Celular , Proliferação de Células , Citocinas/metabolismo , Variações do Número de Cópias de DNA/genética , Células Dendríticas/metabolismo , Redes Reguladoras de Genes , Humanos , Ligantes , Glicoproteínas de Membrana Associadas ao Lisossomo/metabolismo , Monócitos/patologia , Células Mieloides/patologia , Proteínas de Neoplasias/metabolismo , Linfócitos T Reguladores/imunologia , Microambiente Tumoral , Bexiga Urinária/imunologia
2.
Nat Commun ; 11(1): 4545, 2020 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917858

RESUMO

TGF-ß1, ß2 and ß3 bind a common receptor to exert vastly diverse effects in cancer, supporting either tumor progression by favoring metastases and inhibiting anti-tumor immunity, or tumor suppression by inhibiting malignant cell proliferation. Global TGF-ß inhibition thus bears the risk of undesired tumor-promoting effects. We show that selective blockade of TGF-ß1 production by Tregs with antibodies against GARP:TGF-ß1 complexes induces regressions of mouse tumors otherwise resistant to anti-PD-1 immunotherapy. Effects of combined GARP:TGF-ß1/PD-1 blockade are immune-mediated, do not require FcγR-dependent functions and increase effector functions of anti-tumor CD8+ T cells without augmenting immune cell infiltration or depleting Tregs within tumors. We find GARP-expressing Tregs and evidence that they produce TGF-ß1 in one third of human melanoma metastases. Our results suggest that anti-GARP:TGF-ß1 mAbs, by selectively blocking a single TGF-ß isoform emanating from a restricted cellular source exerting tumor-promoting activity, may overcome resistance to PD-1/PD-L1 blockade in patients with cancer.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteínas de Membrana/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Animais , Antineoplásicos Imunológicos/uso terapêutico , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral/transplante , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/imunologia , Células HEK293 , Humanos , Proteínas de Membrana/metabolismo , Camundongos , Neoplasias/imunologia , Neoplasias/patologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
3.
Urologiia ; (4): 73-78, 2020 Sep.
Artigo em Russo | MEDLINE | ID: mdl-32897018

RESUMO

BACKGROUND: The concept of the formation of immunological tolerance is a promising direction for correcting the renal transplant rejection. One of these methods is extracorporeal photochemotherapy (ECP), however, according to the literature, there is no single concept of its mechanisms of action in the formation of immunological tolerance in transplantology. AIM: To assess the effect of the preventive use of extracorporeal photochemotherapy on the factors of cellular immunity that contribute to the development of long-term tolerance in patients after kidney transplantation. MATERIALS AND METHODS: A total of 24 patients after a cadaveric kidney transplantation with group matching were included in the study. During the first six months after transplantation, 15 patients of the main group (MG) underwent 10 sessions of ECP in combination with the standard immunosuppression protocol, and 9 patients of the control group (CG) received only standard immunosuppressive therapy. Immunological studies were carried out by the 3rd year after transplantation. The number of cells expressing the antigens CD3, CD4, CD8, CD19, CD16 and CD56, the expression of co-stimulating molecules CD25, CD28 on T-lymphocytes, the number of T-regulatory cells with the CD3+ CD4+ CD25+ (hi) CD127- phenotype was evaluated. RESULTS: Compared with early post-transplant period, the number of naive CD3+CD4+CD45RO-CD28+ T-cells and CD28+ antigen expression was not different between two groups by 3 years after transplantation and with a group of otherwise healthy individuals (p=0.47 and p=0.26, respectively). Three years after transplantation, the T-helper lymphocyte count (CD3+CD4+) in MG were significantly higher than in CG (48.5+/-7.3% vs. 43.0+/-4.6%, respectively; p=0,04), cytotoxic T-lymphocytes count (CD3+CD8+) was 29.5+/-8.9% in MG, compared to 36.1+/-8.6% in CG (p=0.09), the ratio of CD4+/CD8+ in MG was significantly higher (1.83+/-0.72) than in CG (1.29+/-0.49) (p=0.04). CD19+ lymphocytes count was significantly below normal values in both groups, but in the CG it was more pronounced than in the MG (5.06+/-2.1% and 7.73+/-3%, respectively, (p=0.02) In the long-term period, CD3+CD4+CD25+(hi)CD127- T-regulatory cells count in MG was significantly higher than in CG (20.6+/-10.76*106/L and 12.9+/-4.97*106/l, respectively) (p=0.04). CONCLUSION: ECP initiates immunological tolerance through the activation of a second co-activation pathway between B-7 and CTLA-4 molecules in the early period after kidney transplantation. As a result, a clone of tolerogenic CD3+CD4+ T-lymphocytes is formed, which differentiates into T-regulatory cells and maintains immunological tolerance in the long-term period. Using ECP as a part of combination therapy allows to normalize the indicators of cellular immunity in the long-term period. BACKGROUND: The concept of the formation of immunological tolerance is a promising direction for correcting the renal transplant rejection. One of these methods is extracorporeal photochemotherapy (ECP), however, according to the literature, there is no single concept of its mechanisms of action in the formation of immunological tolerance in transplantology. AIM: To assess the effect of the preventive use of extracorporeal photochemotherapy on the factors of cellular immunity that contribute to the development of long-term tolerance in patients after kidney transplantation. MATERIALS AND METHODS: A total of 24 patients after a cadaveric kidney transplantation with group matching were included in the study. During the first six months after transplantation, 15 patients of the main group (MG) underwent 10 sessions of ECP in combination with the standard immunosuppression protocol, and 9 patients of the control group (CG) received only standard immunosuppressive therapy. Immunological studies were carried out by the 3rd year after transplantation. The number of cells expressing the antigens CD3, CD4, CD8, CD19, CD16 and CD56, the expression of co-stimulating molecules CD25, CD28 on T-lymphocytes, the number of T-regulatory cells with the CD3+ CD4+ CD25+ (hi) CD127- phenotype was evaluated. RESULTS: Compared with early post-transplant period, the number of naive CD3+CD4+CD45RO-CD28+ T-cells and CD28+ antigen expression was not different between two groups by 3 years after transplantation and with a group of otherwise healthy individuals (p=0.47 and p=0.26, respectively). Three years after transplantation, the T-helper lymphocyte count (CD3+CD4+) in MG were significantly higher than in CG (48.5+/-7.3% vs. 43.0+/-4.6%, respectively; p=0,04), cytotoxic T-lymphocytes count (CD3+CD8+) was 29.5+/-8.9% in MG, compared to 36.1+/-8.6% in CG (p=0.09), the ratio of CD4+/CD8+ in MG was significantly higher (1.83+/-0.72) than in CG (1.29+/-0.49) (p=0.04). CD19+ lymphocytes count was significantly below normal values in both groups, but in the CG it was more pronounced than in the MG (5.06+/-2.1% and 7.73+/-3%, respectively, (p=0.02) In the long-term period, CD3+CD4+CD25+(hi)CD127- T-regulatory cells count in MG was significantly higher than in CG (20.6+/-10.76*106/L and 12.9+/-4.97*106/l, respectively) (p=0.04). CONCLUSION: ECP initiates immunological tolerance through the activation of a second co-activation pathway between B-7 and CTLA-4 molecules in the early period after kidney transplantation. As a result, a clone of tolerogenic CD3+CD4+ T-lymphocytes is formed, which differentiates into T-regulatory cells and maintains immunological tolerance in the long-term period. Using ECP as a part of combination therapy allows to normalize the indicators of cellular immunity in the long-term period.


Assuntos
Transplante de Rim , Fotoferese , Rejeição de Enxerto , Humanos , Monitorização Imunológica , Linfócitos T Reguladores/imunologia
4.
Nat Commun ; 11(1): 4011, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32782249

RESUMO

Tryptophan catabolism by the enzymes indoleamine 2,3-dioxygenase 1 and tryptophan 2,3-dioxygenase 2 (IDO/TDO) promotes immunosuppression across different cancer types. The tryptophan metabolite L-Kynurenine (Kyn) interacts with the ligand-activated transcription factor aryl hydrocarbon receptor (AHR) to drive the generation of Tregs and tolerogenic myeloid cells and PD-1 up-regulation in CD8+ T cells. Here, we show that the AHR pathway is selectively active in IDO/TDO-overexpressing tumors and is associated with resistance to immune checkpoint inhibitors. We demonstrate that IDO-Kyn-AHR-mediated immunosuppression depends on an interplay between Tregs and tumor-associated macrophages, which can be reversed by AHR inhibition. Selective AHR blockade delays progression in IDO/TDO-overexpressing tumors, and its efficacy is improved in combination with PD-1 blockade. Our findings suggest that blocking the AHR pathway in IDO/TDO expressing tumors would overcome the limitation of single IDO or TDO targeting agents and constitutes a personalized approach to immunotherapy, particularly in combination with immune checkpoint inhibitors.


Assuntos
Cinurenina/imunologia , Macrófagos/imunologia , Receptores de Hidrocarboneto Arílico/antagonistas & inibidores , Linfócitos T Reguladores/imunologia , Animais , Resistencia a Medicamentos Antineoplásicos , Humanos , Tolerância Imunológica , Imunoterapia , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Camundongos , Neoplasias/imunologia , Neoplasias/terapia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais , Triptofano Oxigenase/genética , Triptofano Oxigenase/metabolismo , Células Tumorais Cultivadas , Microambiente Tumoral
5.
PLoS Pathog ; 16(8): e1008696, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760139

RESUMO

HLA-B*35Px is associated with HIV-1 disease rapid progression to AIDS. However, the mechanism(s) underlying this deleterious effect of this HLA allele on HIV-1 infection outcome has not fully understood. CD8+ T cells play a crucial role to control the viral replication but impaired CD8+ T cells represent a major hallmark of HIV-1 infection. Here, we examined the effector functions of CD8+ T cells restricted by HLA-B*35Px (HLA-B*35:03 and HLA-B*35:02), HLA-B*27/B57 and non-HLA-B*27/B57 (e.g. HLA-A*01, A*02, A*03, A*11, A*24, A*26, B*40, B*08, B*38, B*44). CD8+ T cells restricted by HLA-B*35Px exhibited an impaired phenotype compared with those restricted by HLA-B*27/B57 and even non-HLA-B*27/B57. CD8+ T cells restricted by non-HLA-B*27/B57 when encountered their cognate epitopes upregulated TIM-3 and thus became suppressed by regulatory T cells (Tregs) via TIM-3: Galectin-9 (Gal-9). Strikingly, CD8+ T cells restricted by HLA-B*35Px expressed fewer TIM-3 and therefore did not get suppressed by Tregs, which was similar to CD8+ T cells restricted by HLA-B*27/B57. Instead, CD8+ T cells restricted by HLA-B*35Px upon recognition of their cognate epitopes upregulated CTLA-4. The transcriptional and impaired phenotype (e.g. poor effector functions) of HIV-specific CD8+ T cells restricted by HLA-B*35 was related to persistent CTLA-4, elevated Eomes and blimp-1 but poor T-bet expression. As such, anti-CTLA-4 antibody, Ipilimumab, reversed the impaired proliferative capacity of antigen-specific CD8+ T cells restricted by HLA-B*35Px but not others. This study supports the concept that CD8+ T resistance to Tregs-mediated suppression is related to allele restriction rather than the epitope specificity. Our results aid to explain a novel mechanism for the inability of HIV-specific CD8+ T cells restricted by HLA-B*35Px to control viral replication.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Antígeno CTLA-4/metabolismo , Epitopos de Linfócito T/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Antígeno HLA-B35/imunologia , Replicação Viral , Antígeno CTLA-4/imunologia , Citocinas/metabolismo , Infecções por HIV/metabolismo , Infecções por HIV/virologia , HIV-1/metabolismo , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Ativação Linfocitária/imunologia , Fenótipo , Linfócitos T Reguladores/imunologia
6.
Vascul Pharmacol ; 133-134: 106777, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32750408

RESUMO

Atherosclerosis is a systemic chronic inflammatory disease. Many antioxidants including alpha-lipoic acid (LA), a product of lipoic acid synthase (Lias), have proven to be effective for treatment of this disease. However, the question remains whether LA regulates the immune response as a protective mechanism against atherosclerosis. We initially investigated whether enhanced endogenous antioxidant can retard the development of atherosclerosis via immunomodulation. To explore the impact of enhanced endogenous antioxidant on the retardation of atherosclerosis via immune regulation, our laboratory has recently created a double mutant mouse model, using apolipoprotein E-deficient (Apoe-/-) mice crossbred with mice overexpressing lipoic acid synthase gene (LiasH/H), designated as LiasH/HApoe-/- mice. Their littermates, Lias+/+Apoe-/- mice, served as a control. Distinct redox environments between the two strains of mice have been established and they can be used to facilitate identification of antioxidant targets in the immune response. At 6 months of age, LiasH/HApoe-/- mice had profoundly decreased atherosclerotic lesion size in the aortic sinus compared to their Lias+/+Apoe-/- littermates, accompanied by significantly enhanced numbers of regulatory T cells (Tregs) and anti-oxidized LDL autoantibody in the vascular system, and reduced T cell infiltrates in aortic walls. Our results represent a novel exploration into an environment with increased endogenous antioxidant and its ability to alleviate atherosclerosis, likely through regulation of the immune response. These outcomes shed light on a new therapeutic strategy using antioxidants to lessen atherosclerosis.


Assuntos
Aorta/enzimologia , Doenças da Aorta/prevenção & controle , Aterosclerose/prevenção & controle , Placa Aterosclerótica , Sulfurtransferases/biossíntese , Animais , Aorta/imunologia , Aorta/patologia , Doenças da Aorta/enzimologia , Doenças da Aorta/imunologia , Doenças da Aorta/patologia , Aterosclerose/enzimologia , Aterosclerose/imunologia , Aterosclerose/patologia , Autoanticorpos/sangue , Modelos Animais de Doenças , Indução Enzimática , Lipoproteínas LDL/imunologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Oxirredução , Estresse Oxidativo , Sulfurtransferases/genética , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo
7.
Eur J Endocrinol ; 183(5): R133-R147, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32755992

RESUMO

The SARS-CoV-2 virus responsible for the COVID-19 pandemic has generated an explosion of interest both in the mechanisms of infection leading to dissemination and expression of this disease, and in potential risk factors that may have a mechanistic basis for disease propagation or control. Vitamin D has emerged as a factor that may be involved in these two areas. The focus of this article is to apply our current understanding of vitamin D as a facilitator of immunocompetence both with regard to innate and adaptive immunity and to consider how this may relate to COVID-19 disease. There are also intriguing potential links to vitamin D as a factor in the cytokine storm that portends some of the most serious consequences of SARS-CoV-2 infection, such as the acute respiratory distress syndrome. Moreover, cardiac and coagulopathic features of COVID-19 disease deserve attention as they may also be related to vitamin D. Finally, we review the current clinical data associating vitamin D with SARS-CoV-2 infection, a putative clinical link that at this time must still be considered hypothetical.


Assuntos
Imunidade Adaptativa/imunologia , Infecções por Coronavirus/imunologia , Síndrome da Liberação de Citocina/imunologia , Imunidade Inata/imunologia , Imunocompetência/imunologia , Pulmão/imunologia , Pneumonia Viral/imunologia , Linfócitos T/imunologia , Vitamina D/imunologia , Peptídeos Catiônicos Antimicrobianos/imunologia , Autofagia/imunologia , Betacoronavirus , Defensinas/imunologia , Humanos , Pandemias , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th17/imunologia , Células Th2/imunologia , Vitamina D/análogos & derivados
8.
Science ; 369(6506): 984-988, 2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32820125

RESUMO

Germinal center (GC) responses potentiate the generation of follicular regulatory T (TFR) cells. However, the molecular cues driving TFR cell formation remain unknown. Here, we show that sclerostin domain-containing protein 1 (SOSTDC1), secreted by a subpopulation of follicular helper T (TFH) cells and T-B cell border-enriched fibroblastic reticular cells, is developmentally required for TFR cell generation. Fate tracking and transcriptome assessment in reporter mice establishes SOSTDC1-expressing TFH cells as a distinct T cell population that develops after SOSTDC1- TFH cells and loses the ability to help B cells for antibody production. Notably, Sostdc1 ablation in TFH cells results in substantially reduced TFR cell numbers and consequently elevated GC responses. Mechanistically, SOSTDC1 blocks the WNT-ß-catenin axis and facilitates TFR cell differentiation.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Linfócitos B/imunologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Centro Germinativo/imunologia , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Camundongos , Camundongos Mutantes , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
9.
Mol Immunol ; 125: 1-8, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32610164

RESUMO

BACKGROUND: Follicular helper T (Tfh) cells are a subgroup of activated CD4+ T cells which can assist the formation and maintenance of germinal centers. Follicular regulatory T (Tfr) cells are a new class of regulatory T cells which play a major role in suppressing cells in humoral immunity. In contrast to the role of Tfh cells, Tfr cells can inhibit the function of Tfh cells and B cells. Imbalance of blood Tfr/Tfh ratio resulted in the expansion of auto-reactive B cells and auto-antibody production (). However, the effect of Tfr cells and Tfh cells in the pathogenesis of RA (rheumatoid arthritis) is unclear. The purpose of this study was to investigate the function of Tfr cells and Tfh cells in the pathogenesis of RA. METHODS: We recruited 20 patients fulfilled the the American College of Rheumatology diagnosis criteria and 20 healthy controls (HCs). The number of CD4+CXCR5+Foxp3+ Tfr cells and CD4+CXCR5+ Tfh cells in 20 RA patients were measured by flow cytometry analysis. Furthermore, the correlations between the Tfr/Tfh ratio and the characteristic clinical parameters were assessed. The serum levels of IL-21(interleukin-21), CXCL13 (chemokine (C-X-C motif) ligand 13) and TGF-ß (Transforming growth factor-ß) were measured by ELISA. The formation of ectopic germinal center (GC) of synovial membrane was examined by H&E staining. The transcriptional levels of CXCR5 (C-X-C chemokine receptor type 5), CXCL13, ICOS (inducible co-stimulater) and TGF-ß mRNA were also analyzed. In addition, the expression of Bcl-6 (B-cell lymphoma 6), CXCR5, CXCL13 and ICOS in synovial membrane were examined by immunohistochemistry. RESULTS: RA patients had more Tfh cells in peripheral blood, conversely, the frequency of blood Tfr cells (p < 0.05) and the ratio of Tfr/Tfh were significantly decreased compared to healthy controls (p < 0.05, p < 0.01). Furthermore, the ratio of Tfr/Tfh was negatively correlated with values of ESR (r=-0.57, p < 0.05), RF (r=-0.5275, p < 0.001), CRP (r=-0.4486, p < 0.001), IgG (r=-0.4631, p < 0.05), DAS28 scores (r=-0.5645, p < 0.01), as well as the levels of IL-21(r=-0.7398, p < 0.01), CXCL13 (r=-0.4832, p < 0.05). However, the ratio of Tfr/Tfh was positively with the serum level of TGF-ß (r=0.5115, p < 0.05). Higher mRNA expression of CXCR5, CXCL13, ICOS and lower TGF-ß mRNA expression were observed in RA patients. The serum expression level of IL-21, CXCL13 was significantly increased and expression of TGF-ß was significantly decreased in RA patients. Furthermore, ectopic germinal center formation and higher expression of Bcl-6, CXCR5, ICOS, CXCL13 in the synovial membrane of the joints in RA patients were observed. CONCLUSIONS: The decreased blood CD4+CXCR5+Foxp3+ Tfr cells/CD4+CXCR5+ Tfh cells may be responsible for the immunopathogenesis of RA.


Assuntos
Artrite Reumatoide/sangue , Artrite Reumatoide/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Idoso , Citocinas/sangue , Citocinas/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Mol Immunol ; 125: 162-171, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32688118

RESUMO

BACKGROUND: Baicalin has many biological properties such as anti-oxidation and anti-allergy. The current study aimed to explore the effect of Baicalin on allergic rhinitis (AR) and its potential mechanism of action. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated by density gradient centrifugation. Expression levels of Th17 and Treg cells-related proteins in nasal mucosa and peripheral blood cells were detected by real-time quantitative PCR, flow cytometry and Western blot. The mice were randomly divided into Control, ovalbumin (OVA), l-Baicalin, H-Baicalin, DSGC, 3-MA, and H-Baicalin + Rapa groups. Changes of allergic rhinitis conditions and eosinophil infiltration of the mice were detected and scored by Diff-Quik staining, and histological changes were observed by Hematoxylin & Eosin (H&E) staining and Periodate Schiff (PAS) staining. Serological changes, expression levels of interleukin-17A (IL-17A), interleukin-10 (IL-10), eosinophilic cationic protein (ECP) and anti-OVA-specific antibodies were detected by Enzyme-linked immunosorbent assay (ELISA). RESULTS: Clinical case analysis found that AR patients had a Th17/Treg imbalance and activated autophagy, however, Baicalin restored Th17/Treg cell balance and inhibited autophagy in vitro. in vivo experiments demonstrated that Baicalin inhibited OVA-induced allergic nasal symptoms and the activation of autophagy pathway, which was the same as the regulation of 3-MA, while Rapa could weaken the effects of H-baicalin. Moreover, Baicalin reduced the infiltration of different inflammatory cells of the nasal lavage fluid, prevented the damages to epithelial cells, and improved nasal mucosal thickness and mucus secretion. In addition, Baicalin regulated the balance of mouse anti-OVA-specific antibody levels and expressions of Th17/Treg-associated cytokines. CONCLUSION: Our study revealed that Baicalin can be used to treat AR, and the effect is realized through inhibiting autophagy to regulate Th17/Treg cell differentiation.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Autofagia/efeitos dos fármacos , Flavonoides/farmacologia , Rinite Alérgica/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Células Th17/efeitos dos fármacos , Animais , Autofagia/imunologia , Humanos , Camundongos , Linfócitos T Reguladores/imunologia , Células Th17/imunologia
11.
Scand J Immunol ; 92(4): e12942, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32697349

RESUMO

It is a central tenet of the clonal selection theory, that lymphocyte repertoires are tolerized to self-antigens during their ontogeny. Germinal centres are the sites in secondary lymphoid tissues where B cells undergo affinity maturation and class-switching to produce high-affinity antibodies. This process is crucial, both in our ability to mount protective humoral responses to infections and to vaccinations, but it is also involved in untoward reactions to self-antigens, which underlie autoimmunity. The process of affinity maturation poses a significant challenge to tolerance, as the random nature of somatic hypermutation can introduce novel reactivities. Therefore, it has been a long-standing idea that mechanisms must exist which limit the emergence of autoreactivity at the germinal centre level. One of these mechanisms is the requirement for linked recognition, which imposes on B cells a dependence on centrally tolerant T follicular helper cells. However, as linked recognition can be bypassed by adduct formation of autoantigenic complexes, it has been an appealing notion that there should be an additional layer of dominant mechanisms regulating emergence of autoreactive specificities. About a decade ago, this notion was addressed by the discovery of a novel subset of T regulatory cells localizing to the germinal centre and regulating germinal centre B-cell responses. Here, we detail the progress that has been made towards characterizing this T follicular regulatory cell subset and understanding the functions of these 'guardians of the germinal centre'.


Assuntos
Centro Germinativo/imunologia , Tolerância a Antígenos Próprios/imunologia , Linfócitos T Reguladores/imunologia , Animais , Linfócitos B/imunologia , Humanos
12.
Mikrobiyol Bul ; 54(2): 266-278, 2020 Apr.
Artigo em Turco | MEDLINE | ID: mdl-32723282

RESUMO

Hepatitis B infection is still among the most important public health problems worldwide, even great improvements have been made in the treatment strategies. Hepatitis B virus (HBV) replicates itself by entering the liver cells and simultaneously with the antigen release, many antagonistic immune responses are induced by the regulatory cells including T cell (Treg), T helper 17 (Th17), T helper 1 (Th1) and T helper 2 (Th2) cells. The main function of Treg cells is to develop an appropriate immune response against infection and to suppress the immune response if it is not required. Tregs suppress the effector T cells via secreting immune system supressor cytokines such as Transforming Growth Factor-Beta and interleukin (IL)-10 or contact dependent way. Tregs protect cells from immunopathologic damage of HBV specific T cell immune response and also cause viral persistence, cirrhosis, hepatocellular carsinoma (HCC) and autoimmunity but the mechanisms are not clear, yet. In this study, we aimed to determine whether evaluation of Treg cells and cytokine IL-10 levels together in hepatitis B patients is useful that may indicate the disease survey and response to the treatment. The peripheral blood samples of ninety-one volunteers, including 61 HBV infected patients and 30 healthy controls selected from applicants of Infectious Diseases Outpatient/Clinic Service, were taken. Their CD4+CD25highFOXP3+CD152+CD127lowTreg cell distribution were measured by flow cytometry method, using the recently defined markers. The level of IL-10 cytokine released by immunomodulatory cells was determined by quantitative ELISA method. Treg cell percentages of the patients with acute hepatitis B were below the normal range (2-4%) (median= 1.50%, 0.6-3.5) and the difference was statistically significant (p= 0.005). Treg cell percentages of the patients with chronic hepatitis B were higher than the control group (p< 0.05), and it was found to be related to the parameters used in the diagnosis, staging and follow-up of the disease. IL-10 levels were significantly higher in all hepatitis B clinical stages compared to the healthy controls (median= 11.7, 17.3-44.9) (p< 0.05). Also, in parallel with Treg cells, IL-10 levels were correlated with HBV DNA load and HBsAg levels (r= 0.48, p< 0.02). Treg cells and the related cytokine IL-10 are thought to play an important role in the immunology of HBV infection and therefore, promising to follow up the disease and to develop new therapeutic strategies targeting the Treg cell.


Assuntos
Carcinoma Hepatocelular , Vírus da Hepatite B , Hepatite B , Interleucina-10 , Linfócitos T Reguladores , Hepatite B/sangue , Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B Crônica , Humanos , Interleucina-10/sangue , Neoplasias Hepáticas , Linfócitos T Reguladores/imunologia
13.
Gene ; 757: 144931, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32640308

RESUMO

OBJECTIVE: The aim of this study is to investigate the role of close homolog of L1 (CHL1) on inflammatory bowel disease (IBD), and the correlation with the balance of Th17/Treg. METHODS: Dextran sodium sulfate (DSS)-induced IBD mice model was established. CHL1 knockout (KO) mice and CHL1 wild-type (WT) mice were subjected to DSS. CHL1 expression was detected using qRT-PCR. Weight was recorded daily, and disease activity index (DAI) score was assessed. The colon length and histological changes were measured. The number of neutrophils, macrophages and T cells was observed by immunohistochemistry. The expression of inflammatory cytokines and the proportion of Th17/Treg cells were detected by qRT-PCR and flow cytometry. The expression of RORγt, STAT3 and Foxp3 was detected by using immunohistochemistry and Western blot. RESULTS: CHL1 expression was upregulated in DSS-induced IBD mice. DSS-CHLl-KO mice exhibited less weight loss than the DSS-CHLl-WT mice. The DAI score and histological score were decreased in DSS-CHLl-KO mice compared with DSS-CHLl-WT mice, while colon length was increased. Number of neutrophils, macrophages and T cells, and expression of TNF-α, IL-6, IL-17A, IL-21 and IL-23 were decreased in DSS-CHLl-KO mice, while IL-10 expression was increased. Moreover, CHL1-deficient inhibited Th17 cells differentiation and promoted Treg cells differentiation in IBD mice. CHL1-deficient also inhibited the expression of RORγt and STAT3, and promoted the expression of Foxp3 in IBD mice. CONCLUSION: CHL1-deficient reduces the inflammatory response by regulating the balance of Th17/Treg in mice with IBD. CHL1 is expected to be a new target for the treatment of IBD.


Assuntos
Moléculas de Adesão Celular/genética , Doenças Inflamatórias Intestinais/genética , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Animais , Moléculas de Adesão Celular/deficiência , Diferenciação Celular , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Doenças Inflamatórias Intestinais/sangue , Doenças Inflamatórias Intestinais/imunologia , Interleucinas/genética , Interleucinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Linfócitos T Reguladores/citologia , Células Th17/citologia
14.
Nat Commun ; 11(1): 3272, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32601304

RESUMO

Tumor-draining lymph node (TDLN) invasion by metastatic cells in breast cancer correlates with poor prognosis and is associated with local immunosuppression, which can be partly mediated by regulatory T cells (Tregs). Here, we study Tregs from matched tumor-invaded and non-invaded TDLNs, and breast tumors. We observe that Treg frequencies increase with nodal invasion, and that Tregs express higher levels of co-inhibitory/stimulatory receptors than effector cells. Also, while Tregs show conserved suppressive function in TDLN and tumor, conventional T cells (Tconvs) in TDLNs proliferate and produce Th1-inflammatory cytokines, but are dysfunctional in the tumor. We describe a common transcriptomic signature shared by Tregs from tumors and nodes, including CD80, which is significantly associated with poor patient survival. TCR RNA-sequencing analysis indicates trafficking between TDLNs and tumors and ongoing Tconv/Treg conversion. Overall, TDLN Tregs are functional and express a distinct pattern of druggable co-receptors, highlighting their potential as targets for cancer immunotherapy.


Assuntos
Linfonodos/patologia , Metástase Linfática/imunologia , Linfócitos T Reguladores/imunologia , Antígeno B7-1/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Imunossupressão , Linfonodos/citologia , Linfonodos/imunologia , Metástase Linfática/patologia , Linfócitos T Reguladores/metabolismo
15.
PLoS One ; 15(7): e0232307, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32667911

RESUMO

In the mammalian gut CD103+ve myeloid DCs are known to suppress inflammation threatened by luminal bacteria, but stimuli driving DC precursor maturation towards this beneficial phenotype are incompletely understood. We isolated CD11+ve DCs from mesenteric lymph nodes (MLNs) of healthy mice; CD103+ve DCs were 8-24 fold more likely than CD103-ve DCs to exhibit extensive of prior phagocytosis of apoptotic intestinal epithelial cells. However, CD103+ve and CD103-ve MLN DCs exhibited similar ex vivo capacity to ingest apoptotic cells, indicating that apoptotic cells might drive immature DC maturation towards the CD103+ve phenotype. When cultured with apoptotic cells, myeloid DC precursors isolated from murine bone marrow and characterised as lineage-ve CD103-ve, displayed enhanced expression of CD103 and ß8 integrin and acquired increased capacity to induce T regulatory lymphocytes (Tregs) after 7d in vitro. However, DC precursors isolated from αv-tie2 mice lacking αv integrins in the myeloid line exhibited reduced binding of apoptotic cells and complete deficiency in the capacity of apoptotic cells and/or latent TGF-ß1 to enhance CD103 expression in culture, whereas active TGF-ß1 increased DC precursor CD103 expression irrespective of αv expression. Fluorescence microscopy revealed clustering of αv integrin chains and latent TGF-ß1 at points of contact between DC precursors and apoptotic cells. We conclude that myeloid DC precursors can deploy αv integrin to orchestrate binding of apoptotic cells, activation of latent TGF-ß1 and acquisition of the immunoregulatory CD103+ve ß8+ve DC phenotype. This implies that a hitherto unrecognised consequence of apoptotic cell interaction with myeloid phagocytes is programming that prevents inflammation.


Assuntos
Antígenos CD/metabolismo , Apoptose , Células Dendríticas/imunologia , Regulação da Expressão Gênica , Imunomodulação , Cadeias alfa de Integrinas/metabolismo , Integrina alfaV/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Feminino , Camundongos Endogâmicos C57BL , Células Mieloides/citologia , Fagocitose , Linfócitos T Reguladores/imunologia
16.
Proc Natl Acad Sci U S A ; 117(29): 17166-17176, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32632016

RESUMO

Signaling of 17ß-estradiol (estrogen) through its two nuclear receptors, α and ß (ERα, ERß), is an important mechanism of transcriptional regulation. Although ERs are broadly expressed by cells of the immune system, the mechanisms by which they modulate immune responses remain poorly understood. ERß-specific signaling is reduced in patients with chronic inflammatory diseases, including systemic lupus erythematosus and inflammatory bowel disease, and our previous work suggests that dysregulation of ERß-specific signaling contributes to enhanced intestinal inflammation in female SAMP/YitFC mice, a spontaneous model of Crohn's disease-like ileitis. The present study builds on these prior observations to identify a nonredundant, immunoprotective role for ERß-specific signaling in TGF-ß-dependent regulatory T cell (Treg) differentiation. Using a strain of congenic SAMP mice engineered to lack global expression of ERß, we observed dramatic, female-specific exacerbation of intestinal inflammation accompanied by significant reductions in intestinal Treg frequency and function. Impaired Treg suppression in the absence of ERß was associated with aberrant overexpression of Tsc22d3 (GILZ), a glucocorticoid-responsive transcription factor not normally expressed in mature Tregs, and ex vivo data reveal that forced overexpression of GILZ in mature Tregs inhibits their suppressive function. Collectively, our findings identify a pathway of estrogen-mediated immune regulation in the intestine, whereby homeostatic expression of ERß normally functions to limit Treg-specific expression of GILZ, thereby maintaining effective immune suppression. Our data suggest that transcriptional cross-talk between glucocorticoid and steroid sex hormone signaling represents an important and understudied regulatory node in chronic inflammatory disease.


Assuntos
Receptor beta de Estrogênio/metabolismo , Estrogênios/metabolismo , Inflamação/imunologia , Intestinos/imunologia , Transdução de Sinais/fisiologia , Linfócitos T Reguladores/imunologia , Adolescente , Adulto , Animais , Doença de Crohn/imunologia , Modelos Animais de Doenças , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/genética , Feminino , Glucocorticoides/metabolismo , Humanos , Ileíte/patologia , Doenças Inflamatórias Intestinais/imunologia , Intestinos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Adulto Jovem
17.
Mol Immunol ; 123: 106-115, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32485469

RESUMO

Hepatocytes are the targets in autoimmune hepatitis (AIH) that results in T cell-dependent liver injury. However, hepatocytes may also affect the hepatic T cells in AIH, but the underlying mechanisms are not fully understood. Here we report that hepatocytes could secrete galectin-9 (Gal-9) to suppress the intrahepatic production of Th1 cytokine IFN-γ and restrict AIH development, but hepatocyte damage resulted in opposite effects due to release of TLR2/4 ligands that promoted the intrahepatic production of IL-1ß, IL-6, and IL-12. Through Tim-3, Gal-9 could efficiently suppress the intrahepatic T cell activation despite presence of TLR2/4 ligands, thus attenuating Th1 response in AIH. Intriguingly, intrahepatic IL-6/IL-12 suppressed the effect of TGF-ß on Treg cells. Therefore, in AIH, Gal-9 promoted Foxp3 expression and function of hepatic Treg cells through TL1A signaling, although Treg function was still impaired, compared with that in naive state. Due to its promoting effect on Treg function, together with its effect on T effector cells in a Tim-3-independent way, Gal-9 could attenuate intrahepatic IFN-γ production by hindering the increase of hepatic CD4+CD43+ T cells resulting from extrahepatic T cell activation. TLR2/4 ligands attenuated the effects of Gal-9 on Treg cells and CD4+CD43+ T cells by increasing intrahepatic IL-6 and IL-12. Blocking TLR2/4 ligands could efficiently suppress intrahepatic IFN-γ production, liver injury, and hepatic fibrosis. These findings suggest that hepatocytes paradoxically affect Th1 response in AIH due to Gal-9 expression and TLR2/4 ligands release, and that targeting TLR2/4 signaling may provide an important approach in the therapeutic strategy for AIH.


Assuntos
Galectinas/metabolismo , Hepatite Autoimune/metabolismo , Hepatócitos/fisiologia , Interferon gama/metabolismo , Fígado/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Células Cultivadas , Hepatite Autoimune/imunologia , Hepatite Autoimune/patologia , Ligantes , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Linfócitos T Reguladores/patologia , Células Th1/imunologia , Células Th1/metabolismo
18.
Nat Commun ; 11(1): 2781, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32493900

RESUMO

Mutations disrupting regulatory T (Treg) cell function can cause IPEX and IPEX-related disorders, but whether established disease can be reversed by correcting these mutations is unclear. Treg-specific deletion of the chromatin remodeling factor Brg1 impairs Treg cell activation and causes fatal autoimmunity in mice. Here, we show with a reversible knockout model that re-expression of Brg1, in conjunction with the severe endogenous proinflammatory environment, can convert defective Treg cells into powerful, super-activated Treg cells (SuperTreg cells) that can resolve advanced autoimmunity,  with  Brg1 re-expression in a minor fraction of Treg cells sufficient for the resolution in some cases. SuperTreg cells have enhanced trafficking and regulatory capabilities, but become deactivated as the inflammation subsides, thus avoiding excessive immune suppression. We propose a simple, robust yet safe gene-editing-based therapy for IPEX and IPEX-related disorders that exploits the defective Treg cells and the inflammatory environment pre-existing in the patients.


Assuntos
Diabetes Mellitus Tipo 1/congênito , Diarreia/imunologia , Doenças Genéticas Ligadas ao Cromossomo X/imunologia , Doenças do Sistema Imunitário/congênito , Linfócitos T Reguladores/imunologia , Alelos , Animais , Citocinas/metabolismo , DNA Helicases/deficiência , Diabetes Mellitus Tipo 1/imunologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Fluorescência Verde/metabolismo , Doenças do Sistema Imunitário/imunologia , Ativação Linfocitária/imunologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Nucleares/deficiência , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores CXCR3/metabolismo , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Análise de Sobrevida , Linfócitos T Reguladores/efeitos dos fármacos , Tamoxifeno/farmacologia , Fatores de Transcrição/deficiência
19.
Nature ; 585(7826): 591-596, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32526765

RESUMO

Recent clinical and experimental evidence has evoked the concept of the gut-brain axis to explain mutual interactions between the central nervous system and gut microbiota that are closely associated with the bidirectional effects of inflammatory bowel disease and central nervous system disorders1-4. Despite recent advances in our understanding of neuroimmune interactions, it remains unclear how the gut and brain communicate to maintain gut immune homeostasis, including in the induction and maintenance of peripheral regulatory T cells (pTreg cells), and what environmental cues prompt the host to protect itself from development of inflammatory bowel diseases. Here we report a liver-brain-gut neural arc that ensures the proper differentiation and maintenance of pTreg cells in the gut. The hepatic vagal sensory afferent nerves are responsible for indirectly sensing the gut microenvironment and relaying the sensory inputs to the nucleus tractus solitarius of the brainstem, and ultimately to the vagal parasympathetic nerves and enteric neurons. Surgical and chemical perturbation of the vagal sensory afferents at the hepatic afferent level reduced the abundance of colonic pTreg cells; this was attributed to decreased aldehyde dehydrogenase (ALDH) expression and retinoic acid synthesis by intestinal antigen-presenting cells. Activation of muscarinic acetylcholine receptors directly induced ALDH gene expression in both human and mouse colonic antigen-presenting cells, whereas genetic ablation of these receptors abolished the stimulation of antigen-presenting cells in vitro. Disruption of left vagal sensory afferents from the liver to the brainstem in mouse models of colitis reduced the colonic pTreg cell pool, resulting in increased susceptibility to colitis. These results demonstrate that the novel vago-vagal liver-brain-gut reflex arc controls the number of pTreg cells and maintains gut homeostasis. Intervention in this autonomic feedback feedforward system could help in the development of therapeutic strategies to treat or prevent immunological disorders of the gut.


Assuntos
Encéfalo/citologia , Intestinos/citologia , Intestinos/inervação , Fígado/citologia , Fígado/inervação , Neurônios/fisiologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/imunologia , Vias Aferentes , Animais , Células Apresentadoras de Antígenos/imunologia , Colite/imunologia , Colite/metabolismo , Colite/patologia , Homeostase , Humanos , Intestinos/imunologia , Masculino , Camundongos , Ratos , Receptores Muscarínicos/metabolismo , Baço/citologia , Baço/imunologia , Nervo Vago/fisiologia
20.
Nature ; 583(7816): 447-452, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32499651

RESUMO

Genetic variations underlying susceptibility to complex autoimmune and allergic diseases are concentrated within noncoding regulatory elements termed enhancers1. The functions of a large majority of disease-associated enhancers are unknown, in part owing to their distance from the genes they regulate, a lack of understanding of the cell types in which they operate, and our inability to recapitulate the biology of immune diseases in vitro. Here, using shared synteny to guide loss-of-function analysis of homologues of human enhancers in mice, we show that the prominent autoimmune and allergic disease risk locus at chromosome 11q13.52-7 contains a distal enhancer that is functional in CD4+ regulatory T (Treg) cells and required for Treg-mediated suppression of colitis. The enhancer recruits the transcription factors STAT5 and NF-κB to mediate signal-driven expression of Lrrc32, which encodes the protein glycoprotein A repetitions predominant (GARP). Whereas disruption of the Lrrc32 gene results in early lethality, mice lacking the enhancer are viable but lack GARP expression in Foxp3+ Treg cells, which are unable to control colitis in a cell-transfer model of the disease. In human Treg cells, the enhancer forms conformational interactions with the promoter of LRRC32 and enhancer risk variants are associated with reduced histone acetylation and GARP expression. Finally, functional fine-mapping of 11q13.5 using CRISPR-activation (CRISPRa) identifies a CRISPRa-responsive element in the vicinity of risk variant rs11236797 capable of driving GARP expression. These findings provide a mechanistic basis for association of the 11q13.5 risk locus with immune-mediated diseases and identify GARP as a potential target in their therapy.


Assuntos
Cromossomos Humanos Par 11/genética , Colite/genética , Colite/imunologia , Elementos Facilitadores Genéticos/genética , Predisposição Genética para Doença/genética , Linfócitos T Reguladores/imunologia , Acetilação , Alelos , Animais , Cromossomos de Mamíferos/genética , Feminino , Fatores de Transcrição Forkhead/metabolismo , Histonas/metabolismo , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Sintenia/genética
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