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1.
Plast Reconstr Surg ; 149(2): 216e-228e, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35077416

RESUMO

BACKGROUND: Acute rejection is seen in 85 percent of composite vascular allogeneic transplants despite long-term immunosuppression. Recently, it was reported that the induction of endotoxin tolerance prolonged heart allograft survival in mice. However, it produced side effects in all the animals secondary to the inflammatory reaction. Galactomannan has shown endotoxin tolerance without this side effect in vitro. The authors hypothesized that galactomannan-induced endotoxin tolerance delays acute rejection in vascular allogeneic transplantation without the side effects produced by lipopolysaccharide. METHODS: Twenty-four rat hindlimb transplants were divided into four groups according to the preconditioning received: control, lipopolysaccharide (0.16 ml/kg), galactomannan 72 hours before (galactomannan-72) (8 ml/kg), and galactomannan 24 hours before (galactomannan-24) (8 ml/kg). Median acute rejection time, weight loss, and diarrheal episodes were monitored. Blood samples were collected at 0, 7, 21, 30, 45, and 60 days. Plasma cytokines (i.e., tumor necrosis factor alpha, interferon gamma), peripheral chimerism, and lymphocyte percentages were analyzed. RESULTS: Median allograft survival was 40 days (range, 40 to 44 days) in the control group, 68 days (range, 61 to 71 days) in the lipopolysaccharide group, and 70 days (range, 69 to 73 days) in both galactomannan groups (p = 0.001). Weight loss was higher in the lipopolysaccharide group (p < 0.001), as was the 83.3 percent rate of diarrheal episodes (control, 0 percent, p = 0.015; galactomannan-72, 0 percent, p = 0.015; and galactomannan-24, 16.7 percent, p = 0.02). Preconditioned rats had higher peripheral blood chimerism (lipopolysaccharide, 2.30 ± 0.13 percent; galactomannan-72, 2.63 ±1.46 percent; and galactomannan-24, 2.47 ± 0.19 percent) compared to the control group (2.06 ± 0.36 percent) (lipopolysaccharide, p = 0.04; galactomannan-72, p = 0.002; and galactomannan-24, p = 0.002). CONCLUSIONS: Induction of endotoxin tolerance delays acute rejection in the rat hindlimb transplantation model. Galactomannan preconditioning has no lipopolysaccharide side effects and was equally effective in delaying acute rejection. CLINICAL RELEVANCE STATEMENT: The contributions of this experimental work are very incipient. Although the use of galactomannan in clinical practice requires more studies to assess its safety, there is no doubt that immunomodulation may be one of the responses that solve the problem of long-term immunosuppression.


Assuntos
Tolerância à Endotoxina , Rejeição de Enxerto/etiologia , Membro Posterior/transplante , Doença Aguda , Aloenxertos/irrigação sanguínea , Animais , Modelos Animais de Doenças , Membro Posterior/irrigação sanguínea , Ratos , Fatores de Tempo , Transplante Homólogo
2.
FASEB J ; 34(12): 16179-16190, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33058223

RESUMO

Midkine (MDK) might mediate the proangiogenic effect of intermittent hypoxia (IH) in patients with obstructive sleep apnea (OSA) and cutaneous melanoma (CM). We compare circulating MDK in CM patients with and without OSA, and their relationship with tumor aggressiveness, while exploring in vitro effects of soluble MDK on human lymphatic endothelial (HLEC) and melanoma cell proliferation. In 360 CM patients, sleep studies and MDK serum level measurements were performed. The effect of MDK on cell proliferation was assessed using HLEC and melanoma cell lines with patient sera under both normoxia and IH. MDK levels were higher in severe OSA compared to mild OSA or non-OSA patients, whereas no differences in VEGF levels emerged. In OSA patients, MDK levels correlated with nocturnal hypoxemia and CM mitotic rate. In vitro, MDK promotes HLEC proliferation under IH conditions. Moreover, cultures of the human melanoma cell line C81-61 with sera from patients with the highest MDK levels promoted tumor cell proliferation, which was attenuated after the addition of MDK antibody. These responses were enhanced by IH exposures. In conclusion, in CM patients, OSA severity is associated with higher MDK levels, which, appear to enhance both the lymphangiogenesis as the intrinsic aggressiveness of CM tumor cells.


Assuntos
Proliferação de Células/fisiologia , Melanoma/metabolismo , Midkina/metabolismo , Neovascularização Patológica/metabolismo , Neoplasias Cutâneas/metabolismo , Apneia Obstrutiva do Sono/metabolismo , Adulto , Idoso , Linhagem Celular Tumoral , Células Cultivadas , Estudos Transversais , Feminino , Humanos , Hipóxia/metabolismo , Hipóxia/patologia , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Neovascularização Patológica/patologia , Neoplasias Cutâneas/patologia , Apneia Obstrutiva do Sono/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Melanoma Maligno Cutâneo
3.
Oncoimmunology ; 9(1): 1773204, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32923132

RESUMO

The 'cancer cell fusion' theory is controversial due to the lack of methods available to identify hybrid cells and to follow the phenomenon in patients. However, it seems to be one of the best explanations for both the origin and metastasis of primary tumors. Herein, we co-cultured lung cancer stem cells with human monocytes and analyzed the dynamics and properties of tumor-hybrid cells (THC), as well as the molecular mechanisms beneath this fusion process by several techniques: electron-microscopy, karyotyping, CRISPR-Cas9, RNA-seq, immunostaining, signaling blockage, among others. Moreover, mice models were assessed for in vivo characterization of hybrids colonization and invasiveness. Then, the presence of THCs in bloodstream and samples from primary and metastatic lesions were detected by FACS and immunofluorescence protocols, and their correlations with TNM stages established. Our data indicate that the generation of THCs depends on the expression of CD36 on tumor stem cells and the oxidative state and polarization of monocytes, the latter being strongly influenced by microenvironmental fluctuations. Highly oxidized M2-like monocytes show the strongest affinity to fuse with tumor stem cells. THCs are able to proliferate, colonize and invade organs. THC-specific cell surface signature CD36+CD14+PANK+ allows identifying them in matched primary tumor tissues and metastases as well as in bloodstream from patients with lung cancer, thus functioning as a biomarker. THCs levels in circulation correlate with TNM classification. Our results suggest that THCs are involved in both origin and spread of metastatic cells. Furthermore, they might set the bases for future therapies to avoid or eradicate lung cancer metastasis.


Assuntos
Neoplasias Pulmonares , Monócitos , Células-Tronco Neoplásicas , Animais , Fusão Celular , Humanos , Células Híbridas , Camundongos
4.
J Clin Immunol ; 40(2): 388-398, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32008135

RESUMO

In 2014, a child with broad combined immunodeficiency (CID) who was homozygous for a private BCL10 allele was reported to have complete inherited human BCL10 deficiency. In the present study, we report a new BCL10 mutation in another child with CID who was homozygous for a BCL10 variant (R88X), previously reported as a rare allele in heterozygosis (minor allele frequency, 0.000003986). The mutant allele was a loss-of-expression and loss-of-function allele. As with the previously reported patient, this patient had complete BCL10 deficiency. The clinical phenotype shared features, such as respiratory infections, but differed from that of the previous patient that he did not develop significant gastroenteritis episodes or chronic colitis. Cellular and immunological phenotypes were similar to those of the previous patient. TLR4, TLR2/6, and Dectin-1 responses were found to depend on BCL10 in fibroblasts, and final maturation of T cell and B cell maturation into memory cells was affected. Autosomal-recessive BCL10 deficiency should therefore be considered in children with CID.


Assuntos
Proteína 10 de Linfoma CCL de Células B/genética , Linfócitos B/imunologia , Síndromes de Imunodeficiência/genética , Mutação/genética , Linfócitos T/imunologia , Células Cultivadas , Transtornos Cromossômicos , Homozigoto , Humanos , Memória Imunológica , Lactente , Lectinas Tipo C/metabolismo , Masculino , Infecções Respiratórias , Receptores Toll-Like/metabolismo
5.
J Surg Res ; 249: 232-240, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31796217

RESUMO

BACKGROUND: Galactomannan (GAL), a polysaccharide present on the cell wall of several fungi, has shown an ability to modulate inflammatory responses through the dectin-1 receptor in human macrophages. However, studies evaluating the modulatory properties of this polysaccharide in in vivo inflammatory scenarios are scarce. We hypothesized that GAL pretreatment would modulate local and remote damage related to intestinal reperfusion after an ischemic insult. MATERIALS AND METHODS: Adult male Balb/c mice were subjected to intestinal ischemia-reperfusion injury by reversible occlusion of the superior mesenteric artery, consisting of 45 min of ischemia followed by 3 or 24 h of reperfusion. Intragastric GAL (70 mg/kg) was administered 12 h before ischemia, and saline solution was used in the control animals. Jejunum, lung, and blood samples were taken for the analysis of histology, gene expression, plasma cytokine levels, and nitrosative stress. RESULTS: Intestinal and lung histologic alterations were attenuated by GAL pretreatment, showing significant differences compared with nontreated animals. Interleukin 1ß, monocyte chemoattractant protein 1, and IL-6 messenger RNA expression were considerably downregulated in the small intestine of the GAL group. In addition, GAL treatment significantly prevented plasma interleukin 6 and monocyte chemoattractant protein 1 upregulation and diminished nitrate and nitrite levels after 3 h of intestinal reperfusion. CONCLUSIONS: GAL pretreatment constitutes a novel and promising therapy to reduce local and remote damage triggered by intestinal ischemia-reperfusion injury. Further in vivo and in vitro studies to understand GAL's modulatory effects are warranted.


Assuntos
Mucosa Intestinal/efeitos dos fármacos , Isquemia/complicações , Mananas/administração & dosagem , Traumatismo por Reperfusão/prevenção & controle , Animais , Modelos Animais de Doenças , Galactose/análogos & derivados , Humanos , Mucosa Intestinal/irrigação sanguínea , Mucosa Intestinal/patologia , Jejuno/irrigação sanguínea , Jejuno/efeitos dos fármacos , Jejuno/patologia , Masculino , Camundongos , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/patologia
6.
Sleep ; 43(5)2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-31782790

RESUMO

Immunosurveillance is compromised in patients with obstructive sleep apnea (OSA) as reflected by overexpression of the programmed death cell receptor and its ligand (PD-1/PD-L1) coinhibitory axis. However, the contributions of intermittent hypoxia (IH) and sleep fragmentation (SF) are unclear. We therefore evaluated the expression of PD-1 and PD-L1 on immune cells from mice subjected to IH or SF, and in human cells exposed to IH, oxidative stress, or both conditions. Six-week-old male C57BL/6J mice were exposed to either IH or SF using previously established in vivo models. Moreover, human peripheral blood mononuclear cells (PBMC) were cultured overnight under normoxia, IH, hydrogen peroxide (H2O2), or both. Murine splenocytes and human PBMC were isolated, and labeled using surface-specific antibodies for flow cytometry analysis. Compared to control mice, IH induced higher expression of PD-L1 on F4/80 cells and of PD-1 on CD4+ and CD8+ T-cells, whereas no significant changes emerged after SF. In vitro models of IH and oxidative stress showed similar changes for expression of PD-L1 on human monocytes and PD-1 on CD4+ T-cells. Furthermore, H2O2 increased PD-1 expression on CD8+ T-cells, compromising their cytotoxic capacity assessed by perforin expression, similar to IH. No evidence of synergistic effects was apparent. Therefore, PD-1/PD-L1 upregulation reported in patients with OSA appears to be preferentially mediated by IH rather than SF.


Assuntos
Antígeno B7-H1 , Privação do Sono , Animais , Humanos , Peróxido de Hidrogênio , Hipóxia , Leucócitos Mononucleares , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1 , Regulação para Cima
7.
Genome Med ; 11(1): 66, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31665078

RESUMO

BACKGROUND: Sepsis, a life-threatening organ dysfunction caused by a dysregulated systemic immune response to infection, associates with reduced responsiveness to subsequent infections. How such tolerance is acquired is not well understood but is known to involve epigenetic and transcriptional dysregulation. METHODS: Bead arrays were used to compare global DNA methylation changes in patients with sepsis, non-infectious systemic inflammatory response syndrome, and healthy controls. Bioinformatic analyses were performed to dissect functional reprogramming and signaling pathways related to the acquisition of these specific DNA methylation alterations. Finally, in vitro experiments using human monocytes were performed to test the induction of similar DNA methylation reprogramming. RESULTS: Here, we focused on DNA methylation changes associated with sepsis, given their potential role in stabilizing altered phenotypes. Tolerized monocytes from patients with sepsis display changes in their DNA methylomes with respect to those from healthy controls, affecting critical monocyte-related genes. DNA methylation profiles correlate with IL-10 and IL-6 levels, significantly increased in monocytes in sepsis, as well as with the Sequential Organ Failure Assessment score; the observed changes associate with TFs and pathways downstream to toll-like receptors and inflammatory cytokines. In fact, in vitro stimulation of toll-like receptors in monocytes results in similar gains and losses of methylation together with the acquisition of tolerance. CONCLUSION: We have identified a DNA methylation signature associated with sepsis that is downstream to the response of monocytes to inflammatory signals associated with the acquisition of a tolerized phenotype and organic dysfunction.


Assuntos
Citocinas/genética , Metilação de DNA , DNA/análise , Mediadores da Inflamação/metabolismo , Inflamação/complicações , Monócitos/patologia , Insuficiência de Múltiplos Órgãos/complicações , Sepse/diagnóstico , Idoso , Estudos de Casos e Controles , DNA/genética , Feminino , Humanos , Inflamação/genética , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Monócitos/metabolismo , Insuficiência de Múltiplos Órgãos/genética , Fenótipo , Sepse/etiologia , Sepse/metabolismo , Transdução de Sinais
8.
Respirology ; 24(7): 684-692, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30656807

RESUMO

BACKGROUND AND OBJECTIVE: In obstructive sleep apnoea (OSA), intermittent hypoxia (IH) compromises immune surveillance through the upregulation of the programmed cell death-1 (PD-1) receptor and its ligand (PD-L1). Because the risk of OSA-related cancer depends on age, we assessed PD-L1/PD-1 expression in middle-aged and older patients with OSA as well as in a murine model. METHODS: PD-L1 expression was studied in 41 patients with severe OSA and 40 healthy volunteers (HV), divided into two groups (≤55 and >55 years of age). We used flow cytometry, quantitative PCR (qPCR) and ELISA to determine PD-L1 expression on monocytes and plasma PD-L1 protein levels. Moreover, we analysed PD-L1 expression on an in vivo IH model with old and young mice. RESULTS: In subjects up to 55 years of age, severe OSA increased PD-L1 surface protein and mRNA level expression on monocytes and soluble-PD-L1 protein concentration in plasma compared to HV. PD-L1 and hypoxia-induced factor (HIF)-1α expression correlated with age in HV, whereas in patients with OSA there was a negative relationship. In the mice exposed to IH, PD-L1 expression on F4/80+ splenocytes was also only increased in young animals. HIF-1α expression was significantly higher in patients with OSA than in HV in subjects up to 55 years of age, while PD-L1 expression in monocytes was related to HIF-1α expression in young patients with OSA. CONCLUSION: PD-L1 upregulation in patients with OSA as a consequence of HIF-1α activation occurs mainly in young patients. In older patients with OSA, upregulation was not detected, possibly due to impaired oxygen sensitivity.


Assuntos
Antígeno B7-H1/sangue , Subunidade alfa do Fator 1 Induzível por Hipóxia/sangue , Hipóxia/sangue , Apneia Obstrutiva do Sono/sangue , Adulto , Fatores Etários , Idoso , Animais , Antígeno B7-H1/genética , Estudos de Casos e Controles , Feminino , Humanos , Hipóxia/etiologia , Hipóxia/fisiopatologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Masculino , Camundongos , Pessoa de Meia-Idade , Monócitos/metabolismo , RNA Mensageiro , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/fisiopatologia , Ativação Transcricional , Regulação para Cima
10.
J Cyst Fibros ; 18(5): 630-635, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30442491

RESUMO

BACKGROUND: Cystic fibrosis (CF) is an endotoxin tolerance (ET)-related disease. Given that increased PD-L1 has been reported in ET, its expression and physiological effects on cystic fibrosis monocytes should be studied. METHODS: We analyzed the phenotype and ex vivo response of immune system cells in 32 patients with CF, 19 of them colonized by Pseudomonas aeruginosa. An in vitro model was developed of Pseudomonas aeruginosa colonization using purified lipopolysaccharides (LPS) from one of the most prevalent strains in patients with CF (a CF-adapted Pseudomonas aeruginosa ST395 clone). Changes in the immune response, including cytokine production and T-lymphocyte proliferation, as well as expression of PD-L1, were evaluated. RESULTS: PD-L1 was overexpressed in the monocytes of patients with CF compared with healthy volunteers, and levels of this immune checkpoint were associated with Pseudomonas aeruginosa colonization. In addition, patients with Pseudomonas aeruginosa colonization showed a patent ET status, including poor inflammatory response, reduced HLA-DR expression and T-lymphocyte proliferation impairment. PD-L1/PD-1 blocking assays reverted the impaired adaptive response. Ultimately, monocytes from healthy volunteers cultured in the presence of the clinically relevant strain of Pseudomonas aeruginosa or serum collected from patients with CF colonized by Pseudomonas aeruginosa reproduced the previous observed features. CONCLUSIONS: Pseudomonas aeruginosa colonization in patients with CF was associated with PD-L1 overexpression and impaired T cell response, and LPS from this pathogen induced the observed phenotype. Our findings open new avenues for the use of anti-PD-1/PD-L1 immunotherapy in patients with CF who are colonized by Pseudomonas aeruginosa.


Assuntos
Imunidade Adaptativa/fisiologia , Antígeno B7-H1/metabolismo , Fibrose Cística/imunologia , Fibrose Cística/metabolismo , Monócitos/metabolismo , Pseudomonas aeruginosa , Adulto , Carga Bacteriana , Estudos de Casos e Controles , Fibrose Cística/microbiologia , Feminino , Humanos , Masculino
11.
Front Immunol ; 9: 2008, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30233593

RESUMO

Sepsis is a pathology in which patients suffer from a proinflammatory response and a dysregulated immune response, including T cell exhaustion. A number of therapeutic strategies to treat human sepsis, which are different from antimicrobial and fluid resuscitation treatments, have failed in clinical trials, and solid biomarkers for sepsis are still lacking. Herein, we classified 85 patients with sepsis into two groups according to their blood oxygen saturation (SaO2): group I (SaO2 ≤ 92%, n = 42) and group II (SaO2 > 92%, n = 43). Blood samples were taken before any treatment, and the immune response after ex vivo LPS challenge was analyzed, as well as basal expression of PD-L1 on monocytes and levels of sPD-L1 in sera. The patients were followed up for 1 month. Taking into account reinfection and exitus frequency, a significantly poorer evolution was observed in patients from group I. The analysis of HLA-DR expression on monocytes, T cell proliferation and cytokine profile after ex vivo LPS stimulation confirmed an impaired immune response in group I. In addition, these patients showed both, high levels of PD-L1 on monocytes and sPD-L1 in serum, resulting in a down-regulation of the adaptive response. A blocking assay using an anti-PD-1 antibody reverted the impaired response. Our data indicated that SaO2 levels on admission have emerged as a potential signature for immune status, including PD-L1 expression. An anti-PD-1 therapy could restore the T cell response in hypoxemic sepsis patients with SaO2 ≤ 92% and high PD-L1 levels.


Assuntos
Antígeno B7-H1/metabolismo , Biomarcadores/sangue , Células Sanguíneas/imunologia , Monócitos/imunologia , Oxigênio/sangue , Sepse/diagnóstico , Linfócitos T/imunologia , Imunidade Adaptativa , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Bloqueadores/farmacologia , Antígeno B7-H1/imunologia , Células Cultivadas , Testes Diagnósticos de Rotina , Feminino , Humanos , Tolerância Imunológica , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Sepse/imunologia , Sepse/mortalidade , Análise de Sobrevida
12.
Mediators Inflamm ; 2018: 7373921, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29997451

RESUMO

Obstructive sleep apnea (OSA) is a syndrome characterized by repeated pauses in breathing induced by a partial or complete collapse of the upper airways during sleep. Intermittent hypoxia (IH), a hallmark characteristic of OSA, has been proposed to be a major determinant of cancer development, and patients with OSA are at a higher risk of tumors. Both OSA and healthy monocytes have been found to show enhanced HIF1α expression under IH. Moreover, these cells under IH polarize toward a tumor-promoting phenotype in a HIF1α-dependent manner and influence tumor growth via vascular endothelial growth factor (VEGF). Monocytes from patients with OSA increased the tumor-induced microenvironment and exhibited an impaired cytotoxicity in a 3D tumor in vitro model as a result of the increased HIF1α secretion. Adequate oxygen restoration both in vivo (under continuous positive airway pressure treatment, CPAP) and in vitro leads the monocytes to revert the tumor-promoting phenotype, demonstrating the plasticity of the innate immune system and the oxygen recovery relevance in this context.


Assuntos
Leucócitos Mononucleares/metabolismo , Apneia Obstrutiva do Sono/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Idoso , Biomarcadores/metabolismo , Sobrevivência Celular/fisiologia , Células Cultivadas , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Pessoa de Meia-Idade , Oxigênio/metabolismo , Estudos Prospectivos , Esferoides Celulares/metabolismo
13.
Clin Epigenetics ; 10: 20, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29449904

RESUMO

Background: Integration of human immunodeficiency virus type 1 (HIV-1) into the host genome causes global disruption of the chromatin environment. The abundance level of various chromatin-modifying enzymes produces these alterations and affects both the provirus and cellular gene expression. Here, we investigated potential changes in enzyme expression and global DNA methylation in chronically infected individuals with HIV-1 and compared these changes with non-HIV infected individuals. We also evaluated the effect of viral replication and degree of disease progression over these changes. Results: Individuals with HIV-1 had a significant surge in the expression of DNA and histone methyltransferases (DNMT3A and DNMT3B, SETDB1, SUV39H1) compared with non-infected individuals, with the exception of PRMT6, which was downregulated. Some histone deacetylases (HDAC2 and HDAC3) were also upregulated in patients with HIV. Among individuals with HIV-1 with various degrees of progression and HIV control, the group of treated patients with undetectable viremia showed greater differences with the other two groups (untreated HIV-1 controllers and non-controllers). These latter two groups exhibited a similar behavior between them. Of interest, the overexpression of genes that associate with viral protein Tat (such as SETDB1 along with DNMT3A and HDAC1, and SIRT-1) was more prevalent in treated patients. We also observed elevated levels of global DNA methylation in individuals with HIV-1 in an inverse correlation with the CD4/CD8 ratio. Conclusions: The current study shows an increase in chromatin-modifying enzymes and remodelers and in global DNA methylation in patients with chronic HIV-1 infection, modulated by various levels of viral control and progression.


Assuntos
Linfócitos T CD4-Positivos/química , Metilação de DNA , Perfilação da Expressão Gênica/métodos , Infecções por HIV/genética , Histona Metiltransferases/genética , Adulto , Relação CD4-CD8 , Estudos de Casos e Controles , Montagem e Desmontagem da Cromatina , Progressão da Doença , Feminino , Regulação da Expressão Gênica , Infecções por HIV/imunologia , HIV-1/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Replicação Viral
14.
J Infect Dis ; 217(3): 393-404, 2018 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-28973671

RESUMO

Sepsis, among other pathologies, is an endotoxin tolerance (ET)-related disease. On admission, we classified 48 patients with sepsis into 3 subgroups according to the ex vivo response to lipopolysaccharide. This response correlates with the Acute Physiology and Chronic Health Evaluation (APACHE) II score and the ET degree. Moreover, the ET-related classification determines the outcome of these patients. Programmed cell death-ligand 1 (PD-L1) expression on septic monocytes is also linked with ET status. In addition to the regulation of cytokine production, one of the hallmarks of ET that significantly affects patients with sepsis is T-cell proliferation impairment or a poor switch to the adaptive response. PD-L1/programmed cell death-1 (PD-1) blocking and knockdown assays on tolerant monocytes from both patients with sepsis and the in vitro model reverted the impaired adaptive response. Mechanistically, the transcription factor hypoxia-inducible factor-1α (HIF1α) has been translocated into the nucleus and drives PD-L1 expression during ET in human monocytes. This fact, together with patient classification according to the ex vivo lipopolysaccharide response, opens an interesting field of study and potential personalized clinical applications, not only for sepsis but also for all ET-associated pathologies.


Assuntos
Imunidade Adaptativa , Antígeno B7-H1/biossíntese , Endotoxinas/imunologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Tolerância Imunológica , Sepse/patologia , APACHE , Adulto , Idoso , Idoso de 80 Anos ou mais , Células Cultivadas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia
15.
Eur Respir J ; 50(4)2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29051270

RESUMO

Obstructive sleep apnoea (OSA) is associated with higher cancer incidence, tumour aggressiveness and cancer mortality, as well as greater severity of infections, which have been attributed to an immune deregulation. We studied the expression of programmed cell death (PD)-1 receptor and its ligand (PD-L1) on immune cells from patients with OSA, and its consequences on immune-suppressing activity. We report that PD-L1 was overexpressed on monocytes and PD-1 was overexpressed on CD8+ T-cells in a severity-dependent manner. PD-L1 and PD-1 overexpression were induced in both the human in vitro and murine models of intermittent hypoxia, as well as by hypoxia-inducible factor-1α transfection. PD-L1/PD-1 crosstalk suppressed T-cell proliferation and activation of autologous T-lymphocytes and impaired the cytotoxic activity of CD8+ T-cells. In addition, monocytes from patients with OSA exhibited high levels of retinoic acid related orphan receptor, which might explain the differentiation of myeloid-derived suppressor cells. Intermittent hypoxia upregulated the PD-L1/PD-1 crosstalk in patients with OSA, resulting in a reduction in CD8+ T-cell activation and cytotoxicity, providing biological plausibility to the increased incidence and aggressiveness of cancer and the higher risk of infections described in these patients.


Assuntos
Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/fisiologia , Monócitos/fisiologia , Receptor de Morte Celular Programada 1/metabolismo , Apneia Obstrutiva do Sono/metabolismo , Adulto , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Transdução de Sinais , Apneia Obstrutiva do Sono/diagnóstico , Regulação para Cima
16.
Front Immunol ; 8: 915, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28824640

RESUMO

System dynamics is a powerful tool that allows modeling of complex and highly networked systems such as those found in the human immune system. We have developed a model that reproduces how the exposure of human monocytes to lipopolysaccharides (LPSs) induces an inflammatory state characterized by high production of tumor necrosis factor alpha (TNFα), which is rapidly modulated to enter into a tolerant state, known as endotoxin tolerance (ET). The model contains two subsystems with a total of six states, seven flows, two auxiliary variables, and 14 parameters that interact through six differential and nine algebraic equations. The parameters were estimated and optimized to obtain a model that fits the experimental data obtained from human monocytes treated with various LPS doses. In contrast to publications on other animal models, stimulation of human monocytes with super-low-dose LPSs did not alter the response to a second LPSs challenge, neither inducing ET, nor enhancing the inflammatory response. Moreover, the model confirms the low production of TNFα and increased levels of C-C motif ligand 2 when monocytes exhibit a tolerant state similar to that of patients with sepsis. At present, the model can help us better understand the ET response and might offer new insights on sepsis diagnostics and prognosis by examining the monocyte response to endotoxins in patients with sepsis.

17.
Eur Respir J ; 49(6)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28619958

RESUMO

Obstructive sleep apnoea (OSA) is associated with cancer incidence and mortality. The contribution of the immune system appears to be crucial; however, the potential role of monocytes and natural killer (NK) cells remains unclear.Quantitative reverse transcriptase PCR, flow cytometry and in vitro assays were used to analyse the phenotype and immune response activity in 92 patients with OSA (60 recently diagnosed untreated patients and 32 patients after 6 months of treatment with continuous positive airway pressure (CPAP)) and 29 healthy volunteers (HV).We determined that monocytes in patients with OSA exhibit an immunosuppressive phenotype, including surface expression of glycoprotein-A repetitions predominant protein (GARP) and transforming growth factor-ß (TGF-ß), in contrast to those from the HV and CPAP groups. High levels of TGF-ß were detected in OSA sera. TGF-ß release by GARP+ monocytes impaired NK cytotoxicity and maturation. This altered phenotype correlated with the hypoxic severity clinical score (CT90). Reoxygenation eventually restored the altered phenotypes and cytotoxicity.This study demonstrates that GARP+ monocytes from untreated patients with OSA have an NK-suppressing role through their release of TGF-ß. Our findings show that monocyte plasticity immunomodulates NK activity in this pathology, suggesting a potential role in cancer incidence.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas/métodos , Hipóxia , Células Matadoras Naturais/fisiologia , Proteínas de Membrana/metabolismo , Monócitos/fisiologia , Apneia Obstrutiva do Sono , Fator de Crescimento Transformador beta/metabolismo , Citotoxicidade Imunológica , Feminino , Humanos , Hipóxia/etiologia , Hipóxia/metabolismo , Hipóxia/terapia , Masculino , Pessoa de Meia-Idade , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/imunologia , Apneia Obstrutiva do Sono/terapia , Resultado do Tratamento , Evasão Tumoral
18.
J Immunol ; 198(5): 2038-2046, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28115526

RESUMO

Patients with acute ischemic stroke (AIS) suffer from infections associated with mortality. The relevance of the innate immune system, and monocytes in particular, has emerged as an important factor in the evolution of these infections. The study enrolled 14 patients with AIS, without previous treatment, and 10 healthy controls. In the present study, we show that monocytes from patients with AIS exhibit a refractory state or endotoxin tolerance. The patients were unable to orchestrate an inflammatory response against LPS and expressed three factors reported to control the evolution of human monocytes into a refractory state: IL-1R-associated kinase-M, NFkB2/p100, and hypoxia-inducible factor-1α. The levels of circulating mitochondrial DNA (mtDNA) in patients with AIS correlated with impaired inflammatory response of isolated monocytes. Interestingly, the patients could be classified into two groups: those who were infected and those who were not, according to circulating mtDNA levels. This finding was validated in an independent cohort of 23 patients with AIS. Additionally, monocytes from healthy controls, cultured in the presence of both sera from patients and mtDNA, reproduced a refractory state after endotoxin challenge. This effect was negated by either a TLR9 antagonist or DNase treatment. The present data further extend our understanding of endotoxin tolerance implications in AIS. A putative role of mtDNA as a new biomarker of stroke-associated infections, and thus a clinical target for preventing poststroke infection, has also been identified.


Assuntos
Biomarcadores/sangue , Células Sanguíneas/imunologia , DNA Mitocondrial/sangue , Infecções/imunologia , Isquemia/imunologia , Monócitos/imunologia , Acidente Vascular Cerebral/imunologia , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Células Cultivadas , Endotoxinas/imunologia , Feminino , Humanos , Tolerância Imunológica , Imunidade Inata , Infecções/etiologia , Isquemia/complicações , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/complicações
20.
Oncoimmunology ; 5(12): e1242544, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28123879

RESUMO

Ibrutinib has emerged as a promising therapy for patients with chronic lymphocytic leukemia (CLL) who are nonresponsive to standard therapies. The refractory state of monocytes and T-cell exhaustion in patients with CLL could explain the morbidity and mortality reported in these patients. We studied the effect of ibrutinib on the immune response of four relapsed patients with CLL during the first treatment cycle. We observed the ability to recover the standard response against bacterial stimulus in CD14+ cells, improving levels of phospho-Erk1/2 and antigen presentation. Meanwhile, ibrutinib drove Th1-selective pressure in T lymphocytes, thus, reducing the PD-1 and PDL-1 expression. Our data suggest the impact of BTK inhibition along with immunomodulation on the innate immune response and a switch to the specific adaptive immune response, which might help to decrease infectious complications. The potential effect of ibrutinib on CLL patient outcomes is worthy of further study, because infections could be reduced with the use of ibrutinib.

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