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1.
Entropy (Basel) ; 25(12)2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38136521

RESUMO

Real-time performance and reliability are two critical indicators in cyber-physical production systems (CPPS). To meet strict requirements in terms of these indicators, it is necessary to solve complex job-shop scheduling problems (JSPs) and reserve considerable redundant resources for unexpected jobs before production. However, traditional job-shop methods are difficult to apply under dynamic conditions due to the uncertain time cost of transmission and computation. Edge computing offers an efficient solution to this issue. By deploying edge servers around the equipment, smart factories can achieve localized decisions based on computational intelligence (CI) methods offloaded from the cloud. Most works on edge computing have studied task offloading and dispatching scheduling based on CI. However, few of the existing methods can be used for behavior-level control due to the corresponding requirements for ultralow latency (10 ms) and ultrahigh reliability (99.9999% in wireless transmission), especially when unexpected computing jobs arise. Therefore, this paper proposes a dynamic resource prediction scheduling (DRPS) method based on CI to achieve real-time localized behavior-level control. The proposed DRPS method primarily focuses on the schedulability of unexpected computing jobs, and its core ideas are (1) to predict job arrival times based on a backpropagation neural network and (2) to perform real-time migration in the form of human-computer interaction based on the results of resource analysis. An experimental comparison with existing schemes shows that our DRPS method improves the acceptance ratio by 25.9% compared to the earliest deadline first scheme.

2.
Entropy (Basel) ; 25(9)2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37761588

RESUMO

A 5G system is an advanced solution for industrial wireless motion control. However, because the scheduling model of 5G new radio (NR) is more complicated than those of other wireless networks, existing real-time scheduling algorithms cannot be used to improve the 5G performance. This results in NR resources not being fully available for industrial systems. Supervised learning has been widely used to solve complicated problems, and its advantages have been demonstrated in multiprocessor scheduling. One of the main reasons why supervised learning has not been used for 5G NR scheduling is the lack of training datasets. Therefore, in this paper, we propose two methods based on optimization modulo theories (OMT) and satisfiability modulo theories (SMT) to generate training datasets for 5G NR scheduling. Our OMT-based method contains fewer variables than existing work so that the Z3 solver can find optimal solutions quickly. To further reduce the solution time, we transform the OMT-based method into an SMT-based method and tighten the search space of SMT based on three theorems and an algorithm. Finally, we evaluate the solution time of our proposed methods and use the generated dataset to train a supervised learning model to solve the 5G NR scheduling problem. The evaluation results indicate that our SMT-based method reduces the solution time by 74.7% compared to existing ones, and the supervised learning algorithm achieves better scheduling performance than other polynomial-time algorithms.

3.
J Pediatr Genet ; 12(4): 312-317, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38162156

RESUMO

Wolf-Hirschhorn syndrome (WHS) is a contiguous gene deletion condition. The WHS core phenotype includes developmental delays, intellectual disabilities, seizures, and distinctive facial features. Various other comorbidities have also been reported, such as hearing loss, heart defects, as well as eye problems and kidney problems. In this report, we present a case of WHS accompanied by hyperparathyroidism and hypercalcemia, which has not been previously reported. A girl was born at 37 weeks of gestation by vaginal delivery. She was small for the gestational age (2,045 g) and admitted to neonatal intensive care unit. She had typical WHS facial features and was found to have bilateral small kidneys associated with transient metabolic acidosis and renal insufficiency. She had right-sided sensorineural hearing loss, a small atrial septal defect, and colpocephaly and hypoplasia of corpus callosum. She had a single seizure which was well controlled with an oral antiepileptic medication. Cytogenetic studies demonstrated a large terminal chromosome 4p deletion (21.4 Mb) and 4p duplication (2.1 Mb) adjacent to the deletion. A unique finding in this patient is her consistently elevated levels of parathyroid hormone and serum calcium, suggesting hyperparathyroidism. We present this rare case along with a review of the literature and hope to draw an attention to a potential relationship between WHS and hyperparathyroidism.

4.
Entropy (Basel) ; 25(1)2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36673149

RESUMO

The increasingly large structure of neural networks makes it difficult to deploy on edge devices with limited computing resources. Network pruning has become one of the most successful model compression methods in recent years. Existing works typically compress models based on importance, removing unimportant filters. This paper reconsiders model pruning from the perspective of structural redundancy, claiming that identifying functionally similar filters plays a more important role, and proposes a model pruning framework for clustering-based redundancy identification. First, we perform cluster analysis on the filters of each layer to generate similar sets with different functions. We then propose a criterion for identifying redundant filters within similar sets. Finally, we propose a pruning scheme that automatically determines the pruning rate of each layer. Extensive experiments on various benchmark network architectures and datasets demonstrate the effectiveness of our proposed framework.

5.
J Cereb Blood Flow Metab ; 41(6): 1277-1290, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32933360

RESUMO

Oxygen supply for ischemic brain tissue during stroke is critical to neuroprotection. Remote ischemic conditioning (RIC) treatment is effective for stroke. However, it is not known whether RIC can improve brain tissue oxygen supply. In current study, we employed a mouse model of stroke created by middle cerebral artery occlusion (MCAO) to investigate the effect of RIC on oxygen supply to the ischemic brain tissue using a hypoxyprobe system. Erythrocyte oxygen-carrying capacity and tissue oxygen exchange were assessed by measuring oxygenated hemoglobin and oxygen dissociation curve. We found that RIC significantly mitigated hypoxic signals and decreased neural cell death, thereby preserving neurological functions. The tissue oxygen exchange was markedly enhanced, along with the elevated hemoglobin P50 and right-shifted oxygen dissociation curve. Intriguingly, RIC markedly elevated 2,3-biphosphoglycerate (2,3-BPG) levels in erythrocyte, and the erythrocyte 2,3-BPG levels were highly negatively correlated with the hypoxia in the ischemic brain tissue. Further, adoptive transfusion of 2,3-BPG-rich erythrocytes prepared from RIC-treated mice significantly enhanced the oxygen supply to the ischemic tissue in MCAO mouse model. Collectively, RIC protects against ischemic stroke through improving oxygen supply to the ischemic brain tissue where the enhanced tissue oxygen delivery and exchange by RIC-induced 2,3-BPG-rich erythrocytes may play a role.


Assuntos
2,3-Difosfoglicerato/metabolismo , Isquemia Encefálica/sangue , Eritrócitos/metabolismo , Precondicionamento Isquêmico , Acidente Vascular Cerebral/sangue , Animais , Encéfalo/irrigação sanguínea , Isquemia Encefálica/fisiopatologia , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Acidente Vascular Cerebral/fisiopatologia
6.
Oncotarget ; 11(47): 4411-4420, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33315966

RESUMO

Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic neoplasm that exhibits myelodysplastic and myeloproliferative characteristics with heterogeneous clinical and pathological features. There are limited publications on the ethnic and racial disparity of cytogenetics and genomics in CMML patients. This study aims to define the cytogenetic and molecular landscape in Hispanic CMML patients from Puerto Rico and explore its possible clinical significance. One hundred and eleven (111) Hispanic CMML patients from Puerto Rico were diagnosed in our institute from 2009 to 2018. Karyotypes were available in one hundred and seven (107) patients. Seventeen (17) patients had abnormal karyotypes (17/107, 16%). Compared to previously published data, Hispanic CMML patients in this study had significantly lower rates of overall cytogenetic abnormalities (16% vs 27-28%, p < 0.05) and trisomy 8 (2% vs 7%, p < 0.05). Among one hundred and eleven (111) Hispanic CMML patients, 40-gene myeloid molecular profile tests were performed in fifty-six (56) CMML patients. Gene mutations were identified in fifty-four (54) patients (96%). The most frequent mutated genes were: TET2, SRSF2, ASXL1, ZRSR2, DNMT3A, NRAS, CBL, and RUNX1. Twenty-nine (29) out of fifty-six (56) patients (29/56, 52%) had mutated TET2/wild type ASXL1 (muTET2/wtASXL1). Previous studies indicated that mutated ASXL1, DNMT3A, NRAS, RUNX1, and SETBP1 may associate with an unfavorable prognosis and muTET2/wtASXL1 may associate with a favorable prognosis in CMML patients. Compared to previously published data, Hispanic CMML patients from Puerto Rico in this study had significantly lower mutation rates in ASXL1 and SETBP1, and a higher rate of muTET2/wtASXL1. The findings raise the possibility of a favorable prognosis in Hispanic CMML patients.

7.
Neuroreport ; 30(12): 834-841, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31283710

RESUMO

Remote ischemic preconditioning (RIPC) is an effective regimen for neuroprotection in ischemic stroke. Exosomes are extracellular vesicles released into the blood, where they can transfer signals throughout the body. Several studies have demonstrated that RIPC leads to many changes in circulating exosomes. However, the role of RIPC-induced exosomes in neuroprotection remains to be determined. In the current study, we demonstrate that infusion of enriched plasma exosomes from RIPC-treated mice significantly attenuates infarction size in a murine model of cerebral ischemia compared to control group receiving infusion of exosomes from non-RIPC-treated mice. Further studies show that infusion of RIPC-exosomes markedly improves neurological functions. In line with the above findings, we find that the level of hypoxia inducible transcription factor (HIF)-1α is significantly higher in plasma exosomes from mice subjected to RIPC than those from control mice, which could have contributed to the RIPC-exosome-induced neuroprotection through HIF-1α-induced signals including the enhanced tolerance to hypoxia. To our knowledge, this is the first to demonstrate RIPC protects against cerebral ischemia through inducing neuroprotective exosomes.


Assuntos
Isquemia Encefálica , Exossomos , Precondicionamento Isquêmico , Neuroproteção/fisiologia , Animais , Isquemia Encefálica/metabolismo , Exossomos/metabolismo , Exossomos/transplante , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
8.
ACS Biomater Sci Eng ; 5(5): 2631-2646, 2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31119191

RESUMO

Antigen specificity is a primary goal in developing curative therapies for autoimmune disease. Dendritic cells (DCs), as the most effective antigen presenting cells in the body, represent a key target to mediate restoration of antigen-specific immune regulation. Here, we describe an injectable, dual-sized microparticle (MP) approach that employs phagocytosable ∼1 µm and nonphagocytosable ∼30 µm MPs to deliver tolerance-promoting factors both intracellularly and extracellularly, as well as the type 1 diabetes autoantigen, insulin, to DCs for reprogramming of immune responses and remediation of autoimmunity. This poly(lactic-co-glycolic acid) (PLGA) MP system prevented diabetes onset in 60% of nonobese diabetic (NOD) mice when administered subcutaneously in 8 week old mice. Prevention of disease was dependent upon antigen inclusion and required encapsulation of factors in MPs. Moreover, administration of this "suppressive-vaccine" boosted pancreatic lymph node and splenic regulatory T cells (Tregs), upregulated PD-1 on CD4+ and CD8+ T cells, and reversed hyperglycemia for up to 100 days in recent-onset NOD mice. Our results demonstrate that a MP-based platform can reeducate the immune system in an antigen-specific manner, augment immunomodulation compared to soluble administration of drugs, and provide a promising alternative to systemic immunosuppression for autoimmunity.

9.
Clin Immunol ; 195: 139-148, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29894743

RESUMO

The major metabolic feature of diabetes is hyperglycemia which has been linked to the diabetes inflammatory processes, and diabetes-related vulnerability to infection. In the present study, we assessed how glucose affected PBMCs in type I interferon (IFN) production and subsequent signaling. We found that the moderately elevated glucose promoted, and high glucose suppressed type I IFN production, respectively. Pre-exposure to high glucose rendered monocytes more sensitive to IFN-α stimulation with heightened signaling, whereas, instantaneous addition of high glucose did not exhibit such effect. Consistent with this finding, the mRNA levels of IFN-α-induced IRF-7 in PBMCs were positively correlated with HbA1c levels of diabetes patients. Additionally, we found that high glucose promoted the production of other proinflammatory cytokines/chemokines. This study suggests that hyperglycemia may affect the inflammatory process in diabetes via promoting proinflammatory cytokines, as well as the host defense against microbial infections through impeding type I IFN production and signaling.


Assuntos
Complicações do Diabetes/imunologia , Glucose/metabolismo , Hiperglicemia/imunologia , Infecções/imunologia , Inflamação/imunologia , Interferon Tipo I/metabolismo , Monócitos/imunologia , Adolescente , Adulto , Criança , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Imunidade , Fator Regulador 7 de Interferon/genética , Fator Regulador 7 de Interferon/metabolismo , Masculino , Lectina 1 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Transdução de Sinais , Células THP-1 , Adulto Jovem
10.
J Immunol Res ; 2018: 5463879, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29651443

RESUMO

Dendritic cell (DC) immunotherapy has been effective for prevention of type 1 diabetes (T1D) in NOD mice but fails to protect if initiated after active autoimmunity. As autoreactivity expands inter- and intramolecularly during disease progression, we investigated whether DCs unpulsed or pulsed with ß cell antigenic dominant determinants (DD), subdominant determinants (SD), and ignored determinants (ID) could prevent T1D in mice with advanced insulitis. We found that diabetes was significantly delayed by DC therapy. Of interest, DCs pulsed with SD or ID appeared to provide better protection. T lymphocytes from DC-treated mice acquired spontaneous proliferating capability during in vitro culture, which could be largely eliminated by IL-2 neutralizing antibodies. This trend maintained even 29 weeks after discontinuing DC therapy and appeared antigen-independent. Furthermore, CD4+Foxp3+ T regulatory cells (Tregs) from DC-treated mice proliferated more actively in vitro compared to the controls, and Tregs from DC-treated mice showed significantly enhanced immunosuppressive activities in contrast to those from the controls. Our study demonstrates that DC therapy leads to long-lasting immunomodulatory effects in an antigen-dependent and antigen-independent manner and provides evidence for peptide-based intervention during a clinically relevant window to guide DC-based immunotherapy for autoimmune diabetes.


Assuntos
Células Dendríticas/fisiologia , Diabetes Mellitus Tipo 1/terapia , Imunoterapia Adotiva/métodos , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Animais , Apresentação de Antígeno , Autoantígenos/imunologia , Autoantígenos/metabolismo , Autoimunidade , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Diabetes Mellitus Tipo 1/imunologia , Modelos Animais de Doenças , Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/metabolismo , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Tolerância Imunológica , Epitopos Imunodominantes/imunologia , Epitopos Imunodominantes/metabolismo , Imunomodulação , Células Secretoras de Insulina/imunologia , Células Secretoras de Insulina/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos NOD
11.
Mediators Inflamm ; 2018: 4316584, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30670926

RESUMO

Myeloid-derived suppressor cells (MDSCs) are identified as a heterogeneous population of cells with the function to suppress innate as well as adaptive immune responses. The initial studies of MDSCs were primarily focused on the field of animal tumor models or cancer patients. In cancer, MDSCs play the deleterious role to inhibit tumor immunity and to promote tumor development. Over the past few years, an increasing number of studies have investigated the role of MDSCs in autoimmune diseases. The beneficial effects of MDSCs in autoimmunity have been reported by some studies, and thus, immunosuppressive MDSCs may be a novel therapeutic target in autoimmune diseases. There are some controversial findings as well. Many questions such as the activation, differentiation, and suppressive functions of MDSCs and their roles in autoimmune diseases remain unclear. In this review, we have discussed the current understanding of MDSCs in autoimmune diseases.


Assuntos
Doenças Autoimunes/imunologia , Doenças Autoimunes/terapia , Células Supressoras Mieloides/imunologia , Animais , Autoimunidade/fisiologia , Humanos
12.
Proc Natl Acad Sci U S A ; 114(34): 8980-8985, 2017 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-28784797

RESUMO

Glycans possess significant chemical diversity; glycan binding proteins (GBPs) recognize specific glycans to translate their structures to functions in various physiological and pathological processes. Therefore, the discovery and characterization of novel GBPs and characterization of glycan-GBP interactions are significant to provide potential targets for therapeutic intervention of many diseases. Here, we report the biochemical, functional, and structural characterization of a 130-amino-acid protein, Y3, from the mushroom Coprinus comatus Biochemical studies of recombinant Y3 from a yeast expression system demonstrated the protein is a unique GBP. Additionally, we show that Y3 exhibits selective and potent cytotoxicity toward human T-cell leukemia Jurkat cells compared with a panel of cancer cell lines via inducing caspase-dependent apoptosis. Screening of a glycan array demonstrated GalNAcß1-4(Fucα1-3)GlcNAc (LDNF) as a specific Y3-binding ligand. To provide a structural basis for function, the crystal structure was solved to a resolution of 1.2 Å, revealing a single-domain αßα-sandwich motif. Two monomers were dimerized to form a large 10-stranded, antiparallel ß-sheet flanked by α-helices on each side, representing a unique oligomerization mode among GBPs. A large glycan binding pocket extends into the dimeric interface, and docking of LDNF identified key residues for glycan interactions. Disruption of residues predicted to be involved in LDNF/Y3 interactions resulted in the significant loss of binding to Jurkat T-cells and severely impaired their cytotoxicity. Collectively, these results demonstrate Y3 to be a GBP with selective cytotoxicity toward human T-cell leukemia cells and indicate its potential use in cancer diagnosis and treatment.


Assuntos
Agaricales/metabolismo , Coprinus/metabolismo , Proteínas Fúngicas/metabolismo , Polissacarídeos/metabolismo , Sequência de Aminoácidos , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Proteínas Fúngicas/química , Proteínas Fúngicas/farmacologia , Células HEK293 , Humanos , Células Jurkat , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Multimerização Proteica , Homologia de Sequência de Aminoácidos
13.
EBioMedicine ; 22: 10-17, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28663145

RESUMO

Type 1 diabetes (T1D) has been associated with both genetic and environmental factors. Increasing incidence of T1D worldwide is prompting researchers to adopt different approaches to explain the biology of T1D, beyond the presence and activity of autoreactive lymphocytes. In this review, we propose inflammatory pathways as triggers for T1D. Within the scope of those inflammatory pathways and in understanding the pathogenesis of disease, we suggest that viruses, in particular Coxsackieviruses, act by causing a type 1 interferonopathy within the pancreas and the microenvironment of the islet. As such, this connection and common thread represents an exciting platform for the development of new diagnostic, treatment and/or prevention options.


Assuntos
Infecções por Coxsackievirus/imunologia , Diabetes Mellitus Tipo 1/imunologia , Interferons/metabolismo , Pancreatopatias/virologia , Animais , Microambiente Celular , Imunidade Inata , Ilhotas Pancreáticas/imunologia , Pancreatopatias/imunologia , Transdução de Sinais
14.
Sensors (Basel) ; 17(7)2017 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-28726738

RESUMO

Wireless sensor networks (WSNs) are widely applied in industrial manufacturing systems. By means of centralized control, the real-time requirement and reliability can be provided by WSNs in industrial production. Furthermore, many approaches reserve resources for situations in which the controller cannot perform centralized resource allocation. The controller assigns these resources as it becomes aware of when and where accidents have occurred. However, the reserved resources are limited, and such incidents are low-probability events. In addition, resource reservation may not be effective since the controller does not know when and where accidents will actually occur. To address this issue, we improve the reliability of scheduling for emergency tasks by proposing a method based on a stealing mechanism. In our method, an emergency task is transmitted by stealing resources allocated to regular flows. The challenges addressed in our work are as follows: (1) emergencies occur only occasionally, but the industrial system must deliver the corresponding flows within their deadlines when they occur; (2) we wish to minimize the impact of emergency flows by reducing the number of stolen flows. The contributions of this work are two-fold: (1) we first define intersections and blocking as new characteristics of flows; and (2) we propose a series of distributed routing algorithms to improve the schedulability and to reduce the impact of emergency flows. We demonstrate that our scheduling algorithm and analysis approach are better than the existing ones by extensive simulations.

15.
Front Med ; 11(4): 554-562, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28625015

RESUMO

T cells engineered with chimeric antigen receptor (CAR) have been successfully applied to treat advanced refractory B cell malignancy. However, many challenges remain in extending its application toward the treatment of solid tumors. The immunosuppressive nature of tumor microenvironment is considered one of the key factors limiting CAR-T efficacy. One negative regulator of Tcell activity is lymphocyte activation gene-3 (LAG-3). We successfully generated LAG-3 knockout Tand CAR-T cells with high efficiency using CRISPR-Cas9 mediated gene editing and found that the viability and immune phenotype were not dramatically changed during in vitro culture. LAG-3 knockout CAR-T cells displayed robust antigen-specific antitumor activity in cell culture and in murine xenograft model, which is comparable to standard CAR-T cells. Our study demonstrates an efficient approach to silence immune checkpoint in CAR-T cells via gene editing.


Assuntos
Antígenos CD/imunologia , Sistemas CRISPR-Cas/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Animais , Linhagem Celular Tumoral , Edição de Genes/métodos , Tolerância Imunológica/imunologia , Camundongos , Camundongos Knockout , Microambiente Tumoral/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína do Gene 3 de Ativação de Linfócitos
17.
Sensors (Basel) ; 16(9)2016 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-27589741

RESUMO

Wireless sensor networks (WSNs) have been widely used in industrial systems. Their real-time performance and reliability are fundamental to industrial production. Many works have studied the two aspects, but only focus on single criticality WSNs. Mixed criticality requirements exist in many advanced applications in which different data flows have different levels of importance (or criticality). In this paper, first, we propose a scheduling algorithm, which guarantees the real-time performance and reliability requirements of data flows with different levels of criticality. The algorithm supports centralized optimization and adaptive adjustment. It is able to improve both the scheduling performance and flexibility. Then, we provide the schedulability test through rigorous theoretical analysis. We conduct extensive simulations, and the results demonstrate that the proposed scheduling algorithm and analysis significantly outperform existing ones.

18.
J Immunol Res ; 2016: 2419621, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27556047

RESUMO

Our previous study demonstrated that transfusion of ultraviolet B-irradiated immature dendritic cells (UVB-iDCs) induced alloantigen-specific tolerance between two different strains of mice. Programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) have been suggested to play an important role in maintaining immune tolerance. In the present study, we seek to address whether PD-1/PD-L1 plays a role in the maintenance of UVB-iDC-induced tolerance. We first observe that the UVB-iDC-induced alloantigen-specific tolerance can be maintained for over 6 weeks. Supporting this, at 6 weeks after tolerance induction completion, alloantigen-specific tolerance is still able to be transferred to syngeneic naïve mice through adoptive transfer of CD4+ T cells. Furthermore, skin transplantation study shows that the survival of allogeneic grafts is prolonged in those tolerant recipients. Further studies show that PD-1/PD-L1 interaction is essential for maintaining the induced tolerance as blockade of PD-1/PD-L1 by anti-PD-L1 antibodies largely breaks the tolerance at both cellular and humoral immunological levels. Importantly, we show that PD-1/PD-L1 interaction in tolerant mice is also essential for controlling alloantigen-responding T cells, which have never experienced alloantigens. The above findings suggest that PD-1/PD-L1 plays a crucial role in maintaining immune tolerance induced by UVB-iDCs, as well as in actively controlling effector T cells specific to alloantigens.


Assuntos
Antígeno B7-H1/metabolismo , Tolerância Imunológica , Isoantígenos/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Raios Ultravioleta , Transferência Adotiva , Animais , Sobrevivência de Enxerto/imunologia , Tolerância Imunológica/efeitos da radiação , Ativação Linfocitária/imunologia , Camundongos , Ligação Proteica , Transplante de Pele , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
19.
Int Immunopharmacol ; 31: 158-68, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26735611

RESUMO

In the present study, we report our recently developed new approach to inducing antigen-specific immune response. We use two nucleophilic substitution "click" chemistry processes to successfully couple protein antigens or peptides to mouse spleen cells or T cells by a heterobifunctional crosslinker, succinimidyl-4-(N-maleimidomethyl cyclohexane)-1-carboxylate (SMCC) or sulfo-SMCC. SMCC and its water-soluble analog sulfo-SMCC contain N-hydroxysuccinimide (NHS) ester and maleimide groups, which allow stable covalent conjugation of amine- and sulfhydryl-containing molecules in trans. Protein coupling to cells relies on the free sulfhydryls (thiols) on cell surfaces and the free amines on protein antigens. Although the amount of protein coupled to cells is limited due to the limited number of cell surface thiols, the injection of spleen cells coupled with antigenic proteins, such as keyhole limpet hemocyanin (KLH) or ovalbumin (OVA), induces a potent antigen-specific immune response in vivo, which is even stronger than that induced by the injection of a large dose of protein plus adjuvants. In addition, short peptides coupled to purified splenic T cells also potently elicit peptide-specific T cell proliferation in vivo after injection. Further studies show that antigen-coupled spleen cell treatment leads to augmented IFN-γ-producing T cells. Our study provides a unique antigen delivery method that efficiently distributes antigen to the entire immune system, subsequently eliciting a potent antigen-specific immune response with enhanced IFN-γ production. The findings in the present study suggest that this antigen-cell coupling strategy could be employed in immunotherapy for cancers, infectious diseases as well as immune-mediated disorders.


Assuntos
Antígenos/imunologia , Transplante de Células , Reagentes de Ligações Cruzadas/química , Imunoterapia/métodos , Maleimidas/química , Baço/citologia , Linfócitos T/imunologia , Animais , Antígenos/química , Células Cultivadas , Humanos , Interferon gama/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Baço/química
20.
J Leukoc Biol ; 99(6): 1121-9, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26657791

RESUMO

Myeloid-derived suppressor cells with immunosuppressive functions have been described to be associated with one of the mechanisms by which malignant tumors escape immune surveillance. However, little is known about the role of myeloid-derived suppressor cells in autoimmunity. In the current study, when we attempted to characterize the peritoneal cells in pristane-induced lupus model, as reported previously, we observed that there were markedly increased CD11b(+)Ly6C(hi) monocytes. Surprisingly, this type of monocytes was almost phenotypically identical to the reported monocytic myeloid-derived suppressor cells. Further analysis on how these CD11b(+)Ly6C(hi) cells affected T cell response showed that they strongly suppressed T cell proliferation in vitro in a manner dependent on cell-cell contact, NO, and PGE2. In addition, we found that CD11b(+)Ly6C(hi) monocytes inhibited Th1 differentiation but enhanced development of forkhead box p3(+)CD4(+) regulatory T cells. Consistent with the in vitro experimental results, the in vivo adoptive cell transfer study showed that infusion of pristane-treated syngeneic CD11b(+)Ly6C(hi) monocytes significantly suppressed the production of anti-keyhole limpet hemocyanin antibodies induced by keyhole limpet hemocyanin immunization. In addition, we found that CD11b(+)Ly6C(hi) monocytes were also increased significantly in spleen and peripheral blood and showed immunosuppressive characteristics similar to their peritoneal counterparts. Our findings indicate that CD11b(+)Ly6C(hi) monocytes in a pristane-induced lupus mouse model are monocytic myeloid-derived suppressor cells instead of inflammatory monocytes, as demonstrated previously. To our knowledge, this is the first to describe myeloid-derived suppressor cells in a pristane-induced lupus mouse model, which may lead to a better understanding of the role of CD11b(+)Ly6C(hi) monocytes in this specific pristane-induced lupus model.


Assuntos
Antígenos Ly/metabolismo , Antígeno CD11b/metabolismo , Terapia de Imunossupressão , Lúpus Eritematoso Sistêmico/induzido quimicamente , Lúpus Eritematoso Sistêmico/imunologia , Monócitos/patologia , Transferência Adotiva , Animais , Anticorpos/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Comunicação Celular , Proliferação de Células , Dinoprostona/biossíntese , Modelos Animais de Doenças , Feminino , Hemocianinas/imunologia , Imunização , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/patologia , Camundongos Endogâmicos BALB C , Monócitos/metabolismo , Óxido Nítrico/biossíntese , Baço/patologia , Terpenos
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