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1.
Mol Cancer ; 23(1): 45, 2024 02 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424542

RESUMO

BACKGROUND: In the myeloid compartment of the tumor microenvironment, CD244 signaling has been implicated in immunosuppressive phenotype of monocytes. However, the precise molecular mechanism and contribution of CD244 to tumor immunity in monocytes/macrophages remains elusive due to the co-existing lymphoid cells expressing CD244. METHODS: To directly assess the role of CD244 in tumor-associated macrophages, monocyte-lineage-specific CD244-deficient mice were generated using cre-lox recombination and challenged with B16F10 melanoma. The phenotype and function of tumor-infiltrating macrophages along with antigen-specific CD8 T cells were analyzed by flow cytometry and single cell RNA sequencing data analysis, and the molecular mechanism underlying anti-tumorigenic macrophage differentiation, antigen presentation, phagocytosis was investigated ex vivo. Finally, the clinical feasibility of CD244-negative monocytes as a therapeutic modality in melanoma was confirmed by adoptive transfer experiments. RESULTS: CD244fl/flLysMcre mice demonstrated a significant reduction in tumor volume (61% relative to that of the CD244fl/fl control group) 14 days after tumor implantation. Within tumor mass, CD244fl/flLysMcre mice also showed higher percentages of Ly6Clow macrophages, along with elevated gp100+IFN-γ+ CD8 T cells. Flow cytometry and RNA sequencing data demonstrated that ER stress resulted in increased CD244 expression on monocytes. This, in turn, impeded the generation of anti-tumorigenic Ly6Clow macrophages, phagocytosis and MHC-I antigen presentation by suppressing autophagy pathways. Combining anti-PD-L1 antibody with CD244-/- bone marrow-derived macrophages markedly improved tumor rejection compared to the anti-PD-L1 antibody alone or in combination with wild-type macrophages. Consistent with the murine data, transcriptome analysis of human melanoma tissue single-cell RNA-sequencing dataset revealed close association between CD244 and the inhibition of macrophage maturation and function. Furthermore, the presence of CD244-negative monocytes/macrophages significantly increased patient survival in primary and metastatic tumors. CONCLUSION: Our study highlights the novel role of CD244 on monocytes/macrophages in restraining anti-tumorigenic macrophage generation and tumor antigen-specific T cell response in melanoma. Importantly, our findings suggest that CD244-deficient macrophages could potentially be used as a therapeutic agent in combination with immune checkpoint inhibitors. Furthermore, CD244 expression in monocyte-lineage cells serve as a prognostic marker in cancer patients.


Assuntos
Melanoma , Monócitos , Humanos , Animais , Camundongos , Monócitos/metabolismo , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/metabolismo , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Macrófagos/metabolismo , Linfócitos T CD8-Positivos , Carcinogênese/metabolismo , Microambiente Tumoral , Família de Moléculas de Sinalização da Ativação Linfocitária/metabolismo
2.
Small ; : e2401928, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700385

RESUMO

The formation of a stable solid electrolyte interphase (SEI) layer is crucial for enhancing the safety and lifespan of Li metal batteries. Fundamentally, a homogeneous Li+ behavior by controlling the chemical reaction at the anode/electrolyte interface is the key to establishing a stable SEI layer. However, due to the highly reactive nature of Li metal anodes (LMAs), controlling the movement of Li+ at the anode/electrolyte interface remains challenging. Here, an advanced approach is proposed for coating a sacrificial layer called fluorinated self-assembled monolayer (FSL) on a boehmite-coated polyethylene (BPE) separator to form a stable SEI layer. By leveraging the strong affinity between the fluorine functional group and Li+, the rapid formation of a LiF-rich SEI layer in the cell production and early cycling stage is facilitated. This initial stable SEI formation promotes the subsequent homogeneous Li+ flux, thereby improving the LMA stability and yielding an enhanced battery lifespan. Further, the mechanism behind the stable SEI layer generation by controlling the Li+ dynamics through the FSL-treated BPE separator is comprehensively verified. Overall, this research offers significant contributions to the energy storage field by addressing challenges associated with LMAs, thus highlighting the importance of interfacial control in achieving a stable SEI layer.

3.
Psychiatry Clin Neurosci ; 78(7): 405-415, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38751214

RESUMO

AIM: Short tandem repeats (STRs) are repetitive DNA sequences and highly mutable in various human disorders. While the involvement of STRs in various genetic disorders has been extensively studied, their role in autism spectrum disorder (ASD) remains largely unexplored. In this study, we aimed to investigate genetic association of STR expansions with ASD using whole genome sequencing (WGS) and identify risk loci associated with ASD phenotypes. METHODS: We analyzed WGS data of 634 ASD families and performed genome-wide evaluation for 12,929 STR loci. We found rare STR expansions that exceeded normal repeat lengths in autism cases compared to unaffected controls. By integrating single cell RNA and ATAC sequencing datasets of human postmortem brains, we prioritized STR loci in genes specifically expressed in cortical development stages. A deep learning method was used to predict functionality of ASD-associated STR loci. RESULTS: In ASD cases, rare STR expansions predominantly occurred in early cortical layer-specific genes involved in neurodevelopment, highlighting the cellular specificity of STR-associated genes in ASD risk. Leveraging deep learning prediction models, we demonstrated that these STR expansions disrupted the regulatory activity of enhancers and promoters, suggesting a potential mechanism through which they contribute to ASD pathogenesis. We found that individuals with ASD-associated STR expansions exhibited more severe ASD phenotypes and diminished adaptability compared to non-carriers. CONCLUSION: Short tandem repeat expansions in cortical layer-specific genes are associated with ASD and could potentially be a risk genetic factor for ASD. Our study is the first to show evidence of STR expansion associated with ASD in an under-investigated population.


Assuntos
Transtorno do Espectro Autista , Repetições de Microssatélites , Humanos , Transtorno do Espectro Autista/genética , Repetições de Microssatélites/genética , Masculino , Feminino , Córtex Cerebral/patologia , Fenótipo , Criança , Sequenciamento Completo do Genoma , Aprendizado Profundo , Índice de Gravidade de Doença , Adulto , Expansão das Repetições de DNA/genética
4.
Small ; 19(22): e2207223, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36808806

RESUMO

Composite solid electrolytes (CSEs) are newly emerging components for all-solid-state Li-metal batteries owing to their excellent processability and compatibility with the electrodes. Moreover, the ionic conductivity of the CSEs is one order of magnitude higher than the solid polymer electrolytes (SPEs) by incorporation of inorganic fillers into SPEs. However, their advancement has come to a standstill owing to unclear Li-ion conduction mechanism and pathway. Herein, the dominating effect of the oxygen vacancy (Ovac ) in the inorganic filler on the ionic conductivity of CSEs is demonstrated via Li-ion-conducting percolation network model. Based on density functional theory, indium tin oxide nanoparticles (ITO NPs) are selected as inorganic filler to determine the effect of Ovac on the ionic conductivity of the CSEs. Owing to the fast Li-ion conduction through the Ovac inducing percolation network on ITO NP-polymer interface, LiFePO4 /CSE/Li cells using CSEs exhibit a remarkable capacity in long-term cycling (154 mAh g-1 at 0.5C after 700 cycles). Moreover, by modifying the Ovac concentration of ITO NPs via UV-ozone oxygen-vacancy modification, the ionic conductivity dependence of the CSEs on the surface Ovac from the inorganic filler is directly verified.

5.
Psychol Med ; 53(10): 4811-4819, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36803587

RESUMO

BACKGROUND: Attention deficit-hyperactivity disorder (ADHD) is related to depressive disorder, and adolescents with both present poor outcomes. However, evidence for the safety of concomitantly using a methylphenidate (MPH) and a selective serotonin reuptake inhibitor (SSRI) among adolescent ADHD patients is limited, a literature gap aimed to address through this investigation. METHODS: We conducted a new-user cohort study using a nationwide claims database in South Korea. We identified a study population as adolescents who were diagnosed both ADHD and depressive disorder. MPH-only users were compared with patients who prescribed both a SSRI and a MPH. Fluoxetine and escitalopram users were also compared to find a preferable treatment option. Thirteen outcomes including neuropsychiatric, gastrointestinal, and other events were assessed, taking respiratory tract infection as a negative control outcome. We matched the study groups using a propensity score and used the Cox proportional hazard model to calculate the hazard ratio. Subgroup and sensitivity analyses were conducted in various epidemiologic settings. RESULTS: The risks of all the outcomes between the MPH-only and SSRI groups were not significantly different. Regarding SSRI ingredients, the risk of tic disorder was significantly lower in the fluoxetine group than the escitalopram group [HR 0.43 (0.25-0.71)]. However, there was no significant difference in other outcomes between the fluoxetine and escitalopram groups. CONCLUSION: The concomitant use of MPHs and SSRIs showed generally safe profiles in adolescent ADHD patients with depression. Most of the differences between fluoxetine and escitalopram, except those concerning tic disorder, were not significant.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Estimulantes do Sistema Nervoso Central , Metilfenidato , Transtornos de Tique , Humanos , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Depressão/tratamento farmacológico , Depressão/epidemiologia , Estudos de Coortes , Escitalopram , Fluoxetina/efeitos adversos , Metilfenidato/efeitos adversos , Estimulantes do Sistema Nervoso Central/efeitos adversos
6.
Nucleic Acids Res ; 47(1): e1, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30215766

RESUMO

Existing methods to enrich target regions of genomic DNA based on PCR, hybridization capture, or molecular inversion probes have various drawbacks, including long experiment times and low throughput and/or enrichment quality. We developed CRISPR-Cap, a simple and scalable CRISPR-based method to enrich target regions of dsDNA, requiring only two short experimental procedures that can be completed within two hours. We used CRISPR-Cap to enrich 10 target genes 355.7-fold on average from Escherichia coli genomic DNA with a maximum on-target ratio of 81% and high enrichment uniformity. We also used CRISPR-Cap to measure gene copy numbers and detect rare alleles with frequencies as low as 1%. Finally, we enriched coding sequence regions of 20 genes from the human genome. We envision that CRISPR-Cap can be used as an alternative to other widely used target-enrichment methods, which will broaden the scope of CRISPR applications to the field of target enrichment field.


Assuntos
Sistemas CRISPR-Cas/genética , DNA/genética , Genoma Bacteriano/genética , Genoma Humano/genética , Alelos , Escherichia coli/genética , Humanos , Análise de Sequência de DNA
7.
J Korean Med Sci ; 36(10): e72, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33724739

RESUMO

BACKGROUND: Evidence continues to accumulate that the presence or absence of early trauma (ET) implies unique characteristics in the relationships between suicidal ideation and its risk factors. We examined the relationships among recent stress, depressive symptoms, anxiety symptoms, and suicidal ideation in Korean suicidal women with or without such a history. METHODS: Using data on suicidal adult females, 217 victims and 134 non-victims of ET, from the Korean Cohort for the Model Predicting a Suicide and Suicide-related Behavior, we performed structural equation modeling to investigate the contribution of recent stress, depressive symptoms, and anxiety symptoms on suicidal ideation within each group according to the presence or absence of a history of ET. RESULTS: Structural equation modeling with anxiety and depressive symptoms as potential mediators showed a good fit. Recent stress had a direct effect on both depressive symptoms and anxiety symptoms in both groups. Only anxiety symptoms for victims of ET (standardized regression weight, 0.281; P = 0.005) and depressive symptoms for non-victims of ET (standardized regression weight, 0.326; P = 0.003) were full mediators that increased suicidal ideation. Thus, stress contributed to suicidal ideation by increasing the level of anxiety and depressive symptoms for victims and non-victims, respectively. CONCLUSION: Tailored strategies to reduce suicidal ideation should be implemented according to group type, victims or non-victims of ET. Beyond educating suicidal women in stress-management techniques, it would be effective to decrease anxiety symptoms for those with a history of ET and decrease depressive symptoms for those without such a history.


Assuntos
Ansiedade/etiologia , Depressão/etiologia , Trauma Psicológico , Estresse Psicológico/psicologia , Adulto , Ansiedade/epidemiologia , Ansiedade/psicologia , Depressão/epidemiologia , Depressão/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Trauma Psicológico/epidemiologia , República da Coreia/epidemiologia , Fatores de Risco , Fatores Socioeconômicos , Ideação Suicida , Suicídio/psicologia , Inquéritos e Questionários , Adulto Jovem
8.
Int J Mol Sci ; 22(17)2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34502049

RESUMO

Cancer targeting nanoparticles have been extensively studied, but stable and applicable agents have yet to be developed. Here, we report stable nanoparticles based on hepatitis B core antigen (HBcAg) for cancer therapy. HBcAg monomers assemble into spherical capsids of 180 or 240 subunits. HBcAg was engineered to present an affibody for binding to human epidermal growth factor receptor 1 (EGFR) and to present histidine and tyrosine tags for binding to gold ions. The HBcAg engineered to present affibody and tags (HAF) bound specifically to EGFR and exterminated the EGFR-overexpressing adenocarcinomas under alternating magnetic field (AMF) after binding with gold ions. Using cryogenic electron microscopy (cryo-EM), we obtained the molecular structures of recombinant HAF and found that the overall structure of HAF was the same as that of HBcAg, except with the affibody on the spike. Therefore, HAF is viable for cancer therapy with the advantage of maintaining a stable capsid form. If the affibody in HAF is replaced with a specific sequence to bind to another targetable disease protein, the nanoparticles can be used for drug development over a wide spectrum.


Assuntos
Adenocarcinoma/metabolismo , Antígenos do Núcleo do Vírus da Hepatite B/química , Nanopartículas/química , Microscopia Crioeletrônica , Receptores ErbB/metabolismo , Ouro/química , Células HT29 , Humanos , Nanopartículas/ultraestrutura , Ligação Proteica , Proteínas Recombinantes/química
9.
Gastroenterology ; 154(4): 1047-1060, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29229400

RESUMO

BACKGROUND AND AIMS: CD4+CD25+Foxp3+ T-regulatory (Treg) cells control immune responses and maintain immune homeostasis. However, under inflammatory conditions, Treg cells produce cytokines that promote inflammation. We investigated production of tumor necrosis factor (TNF) by Treg cells in patients with acute hepatitis A (AHA), and examined the characteristics of these cells and association with clinical factors. METHODS: We analyzed blood samples collected from 63 patients with AHA at the time of hospitalization (and some at later time points) and 19 healthy donors in South Korea. Liver tissues were collected from patients with fulminant AHA during liver transplantation. Peripheral blood mononuclear cells were isolated from whole blood and lymphocytes were isolated from liver tissues and analyzed by flow cytometry. Cytokine production from Treg cells (CD4+CD25+Foxp3+) was measured by immunofluorescence levels following stimulation with anti-CD3 and anti-CD28. Epigenetic stability of Treg cells was determined based on DNA methylation patterns. Phenotypes of Treg cells were analyzed by flow cytometry and an RORγt inhibitor, ML-209, was used to inhibit TNF production. Treg cell suppression assay was performed by co-culture of Treg-depleted peripheral blood mononuclear cells s and isolated Treg cells. RESULTS: A higher proportion of CD4+CD25+Foxp3+ Treg cells from patients with AHA compared with controls produced TNF upon stimulation with anti-CD3 and anti-CD28 (11.2% vs 2.8%). DNA methylation analysis confirmed the identity of the Treg cells. TNF-producing Treg cells had features of T-helper 17 cells, including up-regulation of RORγt, which was required for TNF production. The Treg cells had reduced suppressive functions compared with Treg cells from controls. The frequency of TNF-producing Treg cells in AHA patients' blood correlated with their serum level of alanine aminotransferase. CONCLUSIONS: Treg cells from patients with AHA have altered functions compared with Treg cells from healthy individuals. Treg cells from patients with AHA produce higher levels of TNF, gain features of T-helper 17 cells, and have reduced suppressive activity. The presence of these cells is associated with severe liver injury in patients with AHA.


Assuntos
Hepatite A/metabolismo , Fígado/metabolismo , Linfócitos T Reguladores/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Doença Aguda , Antígenos CD/imunologia , Antígenos CD/metabolismo , Apirase/imunologia , Apirase/metabolismo , Estudos de Casos e Controles , Células Cultivadas , Metilação de DNA , Epigênese Genética , Fatores de Transcrição Forkhead/imunologia , Fatores de Transcrição Forkhead/metabolismo , Hepatite A/diagnóstico , Hepatite A/imunologia , Hepatite A/virologia , Vírus da Hepatite A/imunologia , Vírus da Hepatite A/patogenicidade , Interações Hospedeiro-Patógeno , Humanos , Subunidade alfa de Receptor de Interleucina-2/imunologia , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Fígado/imunologia , Fígado/patologia , Fígado/virologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Fenótipo , Índice de Gravidade de Doença , Transdução de Sinais , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/virologia , Células Th17/imunologia , Células Th17/metabolismo , Células Th17/virologia , Fatores de Tempo , Fator de Necrose Tumoral alfa/imunologia
10.
Compr Psychiatry ; 89: 67-77, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30597426

RESUMO

BACKGROUND: Despite heterogeneity of older people in suicidal behavior, research identifying characteristics by age groups is scarce. We examined baseline features of older community-dwelling suicidal ideators by dichotomized age groups and the 6-month trajectory of their suicidal ideation along with its related psychopathology. Predictors of suicidal ideation within each group were investigated. METHODS: Older community-dwelling suicidal ideators enrolled in the Korean Cohort for the Model Predicting a Suicide and Suicide-related Behavior study were subdivided into the "young-old (65-74 years)" and "old-old (≥75 years)" group. Baseline, 1-, and 6-month assessments were compared. Within each group, multiple regression analysis using rating scales (Patient Health Questionnaire-9, Beck Anxiety Inventory, Alcohol Use Disorders Identification Test, Stress Questionnaire for Korean National Health and Nutrition Examination Survey-Short Form, and Social Relationships Scale) was conducted to identify predictors of suicidal ideation measured with the intensity subscale of the Columbia-Suicide Severity Rating Scale. Two-way repeated-measures analysis of variance (RM-ANOVA) was used to compare changes in suicidal ideation, depression, anxiety between age groups over time, and one-way RM-ANOVA to examine changes within each age group. RESULTS: Among 29 "young-old" and 53 "old-old" ideators, the latter were less likely to be receiving psychiatric treatment (odds ratio [OR] = 4.065) and make suicide attempts (OR = 2.874), whereas the former revealed greater levels of anxiety and stress. Baseline depression and stress in the "young-old" group and the "old-old" group, respectively, predicted the intensity of suicidal ideation at both baseline and 1-month assessments. No significant age group x time interactions on suicidal ideation and depression were found. However, within each age group, both suicidal ideation and depression significantly decreased only during the first month with no further improvement. CONCLUSION: We speculate cautiously that more attention may need to be paid to the "old-old" ideators in the evaluation of psychiatric issues and for referral to psychiatrists. To decrease suicidal ideation, tailored approaches involving proactive, timely management of depression in the "young-old" and interventions focusing on stress reduction in the "old-old," would be helpful.


Assuntos
Fatores Etários , Vida Independente/psicologia , Ideação Suicida , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Ansiedade/psicologia , Depressão/psicologia , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Inquéritos Nutricionais , Tentativa de Suicídio/psicologia , Inquéritos e Questionários
11.
Compr Psychiatry ; 88: 29-38, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30468986

RESUMO

BACKGROUND: The Korean Cohort for the Model Predicting a Suicide and Suicide-related Behavior (K-COMPASS) study is a prospective, naturalistic, observational cohort study, aiming to identify predictors of suicide attempt and suicide characteristics in the Korean suicidal population. The findings intend to contribute to a thorough understanding of suicidal phenomena and development of suicide prevention guidelines. The present cross-section study examines the study rationale, methodology, and baseline characteristics of the participants. METHODS: Participants were enrolled via the hospital and community gateways, establishing the hospital-based cohort (HC) and community-based cohort (CC), respectively. Baseline assessment was conducted on sociodemographic, clinical, diagnostic, and psychopathological aspects. The Columbia-Suicide Severity Rating Scale was used to investigate suicidality. RESULTS: A total of 800 suicidal people aged 15 years or older were enrolled from 8 university hospitals and 8 community mental health welfare centers (CMHWCs), among whom 480 (60%) were suicidal ideators and 320 (40%) were attempters. The ideators comprised 207 CC and 273 HC participants, whereas the attempters, 34 CC and 286 HC participants. Despite their lower severity in some measures, including suicidal ideation, compared with their HC counterparts, the CC participants within each group of ideators or attempters presented clinically significant psychopathology. Moreover, alcohol use problems and past suicide attempt were more likely to be found in CC participants. Only 11.1% to 21.6% of the participants in each of the four groups (defined by the cohorts and the ideators/attempters) were on any type of psychiatric treatment. CONCLUSIONS: Suicidal visitors to CMHWCs need to be as closely monitored as suicidal patients in university hospitals, especially considering their association with problem drinking and past suicide attempt. A cautious assumption is that the high suicide rate in Korea might be partly attributable to the low proportion of patients receiving psychiatric services.


Assuntos
Alcoolismo/epidemiologia , Alcoolismo/psicologia , Ideação Suicida , Tentativa de Suicídio/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alcoolismo/diagnóstico , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , República da Coreia/epidemiologia , Tentativa de Suicídio/tendências , Adulto Jovem
12.
Thorax ; 73(3): 286-289, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28724637

RESUMO

We evaluated the clinical characteristics, cytokine/chemokine concentrations, viral shedding and antibody kinetics in 30 patients with Middle East respiratory syndrome (MERS), including 6 non-survivors admitted to 3 MERS-designated hospitals. Old age, low albumin, altered mentality and high pneumonia severity index score at admission were risk factors for mortality. In addition, severe signs of inflammation at initial presentation (at hospital days 1-4), such as high inducible protein-10 (p=0.0013), monocyte chemoattractant protein-1 (p=0.0007) and interleukin 6 (p=0.0007) concentrations, and poor viral control (high viral load at hospital days 5-10, p<0.001) without adequate antibody titres (low antibody titre at hospital days 11-16, p=0.07) during the course of disease, were associated with mortality.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Coronavirus/mortalidade , Citocinas/sangue , Carga Viral/genética , Coronavirus/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Risco , Taxa de Sobrevida
14.
Biotechnol Bioeng ; 115(6): 1437-1449, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29460954

RESUMO

The endocytosis-mediating performances of two types of peptide ligands, cell receptor binding peptide (CRBP) and cell membrane penetrating peptide (CMPP), were analyzed and compared using a common carrier of peptide ligands-human ferritin heavy chain (hFTH) nanoparticle. Twenty-four copies of a CMPP(human immunodeficiency virus-derived TAT peptide) and/or a CRBP (peptide ligand with strong and specific affinity for either human integrin(αv ß3 ) or epidermal growth factor receptor I (EGFR) that is overexpressed on various cancer cells) were genetically presented on the surface of each hFTH nanopariticle. The quantitative level of endocytosis and intracellular localization of fluorescence dye-labeled CRBP- and CMPP-presenting nanoparticles were estimated in the in vitro cultures of integrin- and EGFR-overexpressing cancer and human dermal fibroblast cells(control). From the cancer cell cultures treated with the CMPP- and CRBP-presenting nanoparticles, it was notable that CRBPs resulted in quantitatively higher level of endocytosis than CMPP (TAT) and successfully transported the nanoparticles to the cytosol of cancer cells depending on concentration and treatment period of time, whereas TAT-mediated endocytosis localized most of the nanoparticles within endosomal vesicles under the same conditions. These novel findings provide highly useful informations to many researchers both in academia and in industry who are interested in developing anticancer drug delivery systems/carriers.


Assuntos
Membrana Celular/metabolismo , Endocitose , Nanopartículas/metabolismo , Peptídeos/metabolismo , Receptores de Superfície Celular/metabolismo , Apoferritinas/metabolismo , Células Cultivadas , Receptores ErbB/metabolismo , Humanos , Integrina alfaVbeta3/metabolismo , Nanopartículas/química , Ligação Proteica , Propriedades de Superfície
15.
Small ; 12(31): 4241-53, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27356892

RESUMO

Human ferritin heavy-chain nanoparticle (hFTH) is genetically engineered to present tumor receptor-binding peptides (affibody and/or RGD-derived cyclic peptides, named 4CRGD here) on its surface. The affibody and 4CRGD specifically and strongly binds to human epidermal growth factor receptor I (EGFR) and human integrin αvß3, respectively, which are overexpressed on various tumor cells. Through in vitro culture of EGFR-overexpressing adenocarcinoma (MDA-MB-468) and integrin-overexpressing glioblastoma cells (U87MG), it is clarified that specific interactions between receptors on tumor cells and receptor-binding peptides on engineered hFTH is critical in active tumor cell targeting. After labeling with the near-infrared fluorescence dye (Cy5.5) and intravenouse injection into MDA-MB-468 or U87MG tumor-bearing mice, the recombinant hFTHs presenting either peptide or both of affibody and 4CRGD are successfully delivered to and retained in the tumor for a prolonged period of time. In particular, the recombinant hFTH presenting both affibody and 4CRGD notably enhances in vivo detection of U87MG tumors that express heterogeneous receptors, integrin and EGFR, compared to the other recombinant hFTHs presenting either affibody or 4CRGD only. Like affibody and 4CRGD used in this study, other multiple tumor receptor-binding peptides can be also genetically introduced to the hFTH surface for actively targeting of in vivo tumors with heterogenous receptors.


Assuntos
Ferritinas/química , Nanopartículas/química , Peptídeos/química , Animais , Carbocianinas/química , Linhagem Celular Tumoral , Humanos , Integrina alfaVbeta3/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ligação Proteica
16.
Biotechnol Bioeng ; 113(2): 268-74, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26222886

RESUMO

The hepatitis B virus (HBV) capsid-based recombinant particles, which display both major hydrophilic region of HBV surface antigen (HBV-MHR) and B domain of Staphylococcal protein A (SPAB ), were produced using Escherichia coli as expression host. SPAB was used as an adjuvant to elicit the immune response to HBV-MHR, and its adjuvant effect in the immunized mice was estimated with varying the position and amount of SPAB on the HBV capsid particles. Compared to the emulsified aluminum gel (alum gel) that is a currently commercialized vaccine adjuvant, SPAB caused the significantly higher level of anti-HBV immunoglobulin G (IgG) titer and seroconversion rate, and notably SPAB at the most surface-exposed position on the recombinant particle led to the highest immune response. Moreover, SPAB caused much lower ratio of IgG1 to IgG2a compared to alum gel, indicating that helper T-cell 1-mediated immune response (responsible for cytotoxic T-cell stimulation) is relatively more stimulated by SPAB , unlike alum gel that mainly stimulates helper T-cell 2-mediated immune response (responsible for B-cell stimulation). Although HBV-MHR and HBV capsid particle were used as proof-of-concept in this study, SPAB can be used as a highly effective adjuvant with other disease-specific antigens on the surface of other virus-like particles to produce various recombinant vaccines with high potency.


Assuntos
Adjuvantes Imunológicos/farmacologia , Capsídeo/imunologia , Vacinas contra Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Proteína Estafilocócica A/farmacologia , Adjuvantes Imunológicos/genética , Animais , Escherichia coli/genética , Anticorpos Anti-Hepatite B/sangue , Vacinas contra Hepatite B/administração & dosagem , Vacinas contra Hepatite B/genética , Vírus da Hepatite B/genética , Imunoglobulina G/sangue , Camundongos , Proteína Estafilocócica A/genética , Células Th1/imunologia , Resultado do Tratamento , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
17.
Gut ; 64(8): 1303-13, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25007815

RESUMO

OBJECTIVE: Foxp3(+)CD4(+)CD25(+) regulatory T cells (Tregs) control immune responses, but their role in acute viral hepatitis remains elusive. Herein, we investigated alteration in the peripheral blood Treg population during acute hepatitis A (AHA) and its implication in the immune-mediated liver injury. DESIGN: The study included 71 patients with AHA, and peripheral blood mononuclear cells (PBMCs) were isolated. The suppressive activity of Treg population was determined by assessing anti-CD3/CD28-stimulated proliferation of Treg-depleted and reconstituted PBMCs. Treg cell frequency, phenotype and apoptosis in PBMCs were analysed by flow cytometry. RESULTS: The frequency of circulating Tregs was reduced during AHA. Moreover, the suppressive activity of the total Treg pool in the peripheral blood was attenuated during AHA. Treg frequency and suppressive activity of the Treg population inversely correlated with the serum alanine aminotransferase level. Fas was overexpressed on Tregs during AHA, suggesting their susceptibility to Fas-induced apoptosis. Indeed, increased apoptotic death was observed in Tregs of patients with AHA compared with healthy controls. In addition, agonistic anti-Fas treatment further increased apoptotic death of Tregs from patients with AHA. The decreased Treg frequency and Fas overexpression on Tregs were not observed in other acute liver diseases such as acute hepatitis B, acute hepatitis C and toxic/drug-induced hepatitis. CONCLUSIONS: The size of the Treg pool was contracted during AHA, resulting from apoptosis of Tregs induced by a Fas-mediated mechanism. Decrease in Treg numbers led to reduced suppressive activity of the Treg pool and consequently resulted in severe liver injury during AHA.


Assuntos
Antivirais/efeitos adversos , Apoptose/imunologia , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Hepatite A/imunologia , Imunidade Celular , Linfócitos T Reguladores/imunologia , Doença Aguda , Adulto , Antivirais/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Feminino , Citometria de Fluxo , Hepatite A/tratamento farmacológico , Humanos , Masculino
18.
Eur J Immunol ; 44(8): 2360-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24825439

RESUMO

Growing concerns about unpredictable influenza pandemics require a broadly protective vaccine against diverse influenza strains. One of the promising approaches was a T cell-based vaccine, but the narrow breadth of T-cell immunity due to the immunodominance hierarchy established by previous influenza infection and efficacy against only mild challenge condition are important hurdles to overcome. To model T-cell immunodominance hierarchy in humans in an experimental setting, influenza-primed C57BL/6 mice were chosen and boosted with a mixture of vaccinia recombinants, individually expressing consensus sequences from avian, swine, and human isolates of influenza internal proteins. As determined by IFN-γ ELISPOT and polyfunctional cytokine secretion, the vaccinia recombinants of influenza expanded the breadth of T-cell responses to include subdominant and even minor epitopes. Vaccine groups were successfully protected against 100 LD50 challenges with PR/8/34 and highly pathogenic avian influenza H5N1, which contained the identical dominant NP366 epitope. Interestingly, in challenge with pandemic A/Cal/04/2009 containing mutations in the dominant epitope, only the group vaccinated with rVV-NP + PA showed improved protection. Taken together, a vaccinia-based influenza vaccine expressing conserved internal proteins improved the breadth of influenza-specific T-cell immunity and provided heterosubtypic protection against immunologically close as well as distant influenza strains.


Assuntos
Vacinas contra Influenza/imunologia , Vacinas contra Influenza/farmacologia , Influenza Humana/prevenção & controle , Vaccinia virus/imunologia , Animais , Modelos Animais de Doenças , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Virus da Influenza A Subtipo H5N1/imunologia , Influenza Humana/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Suínos , Linfócitos T/imunologia , Vacínia/imunologia
19.
Appl Microbiol Biotechnol ; 99(12): 5203-15, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25683663

RESUMO

High temperatures (30-36 °C) inhibited astaxanthin accumulation in Haematococcus pluvialis under photoautotrophic conditions. The depression of carotenogenesis was primarily attributed to excess intracellular less reactive oxygen species (LROS; O2 (-) and H2O2) levels generated under high temperature conditions. Here, we show that the heat stress-driven inefficient astaxanthin production was improved by accelerating the iron-catalyzed Haber-Weiss reaction to convert LROS into more reactive oxygen species (MROS; O2 and OH·), thereby facilitating lipid peroxidation. As a result, during 18 days of photoautotrophic induction, the astaxanthin concentration of cells cultured in high temperatures in the presence of iron (450 µM) was dramatically increased by 75 % (30 °C) and 133 % (36 °C) compared to that of cells exposed to heat stress alone. The heat stress-driven Haber-Weiss reaction will be useful for economically producing astaxanthin by reducing energy cost and enhancing photoautotrophic astaxanthin production, particularly outdoors utilizing natural solar radiation including heat and light for photo-induction of H. pluvialis.


Assuntos
Clorófitas/metabolismo , Processos Autotróficos/efeitos da radiação , Clorófitas/crescimento & desenvolvimento , Clorófitas/efeitos da radiação , Temperatura Alta , Luz , Espécies Reativas de Oxigênio/metabolismo , Xantofilas/biossíntese
20.
Protein Expr Purif ; 101: 91-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24945073

RESUMO

When used as an N-terminal fusion expression partner, the Escherichia coli stress-responsive protein, CysQ dramatically increased the cytoplasmic solubility of various aggregation-prone heterologous proteins: Pseudomonas putida cutinase (CUT), human granulocyte colony-stimulating factor (hG-CSF), human ferritin light chain (hFTN-L), arginine deiminase (ADI), human interleukin-2 (IL2), human activation induced cytidine deaminase (AID), and deletion mutant of human glutamate decarboxylase (GAD448-585). As compared with well-known fusion tags such as glutathione-S-transferase (GST) and maltose-binding protein (MBP), the performance of CysQ as solubility enhancer was evidently better than GST and was similar to or better than MBP for the seven heterologous proteins above. This is likely due to the intrinsic ability of CysQ to form its native conformation, probably promoting the binding of molecular chaperones during the folding of CysQ-fusion protein. When used as a substrate, p-nitrophenyl butyrate (PNB) was successfully hydrolyzed to p-nitrophenol by CysQ-CUT fusion mutant. Even after CysQ was removed, the solubility of hFTN-L and hG-CSF, the secondary structure of hG-CSF, and self-assembly activity of hFTN-L were successfully maintained. Conclusively, it seems that CysQ is a highly effective solubility enhancer and fusion expression partner for the production of a variety of bio-active recombinant proteins.


Assuntos
Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/metabolismo , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Apoferritinas/metabolismo , Butiratos/química , Citoplasma/metabolismo , Escherichia coli/enzimologia , Escherichia coli/metabolismo , Fator Estimulador de Colônias de Granulócitos/metabolismo , Humanos , Chaperonas Moleculares/metabolismo , Nitrofenóis/química , Agregados Proteicos/fisiologia , Dobramento de Proteína , Pseudomonas putida/enzimologia , Solubilidade
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