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1.
Med Sci Monit ; 29: e938570, 2023 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-37270667

RESUMEN

BACKGROUND The poor ergonomic design of patient monitoring systems can cause user errors and patient harm. This paper presents the results of a comparative usability study based on user experience and the results of a user preference survey. MATERIAL AND METHODS We conducted a usability study of 3 patient monitoring systems: Mediana M50, Philips IntelliVue MP70, and Philips IntelliVue MX700. Thirty-nine Coronary Care Unit nurses and 19 Pulmonology and Allergy Care Unit nurses participated in this usability study. User experience was assessed with the Post-Study System Usability Questionnaire and the National Aeronautics and Space Administration Task Load Index. A user preference survey was conducted to evaluate the subjective medical device design preferences for the M50 system's user interface. RESULTS Nurses from the Coronary Care Unit recognized a higher system usability for the MP70 than the M50 (P=0.001) system, and a lower workload for the MP70 compared with the M50 (P=0.005) system. There was no significant (P>0.05) difference in perceived system usability and workload between the M50 and MX700 systems for the nurses from the Pulmonology and Allergy Care Unit. Nurses preferred to activate the arrhythmia alarms except for the ST alarms and missed the beat alarm. They also preferred having a wave freeze function, standby mode, and early warning scoring function, which provides a signal for a patient's deterioration in health. CONCLUSIONS The study provides valuable data on a user interface evaluation based on user experience and preference. The outcome of this study will be helpful for designing next-generation patient monitors with improved patient safety.


Asunto(s)
Ergonomía , Interfaz Usuario-Computador , Humanos , Carga de Trabajo , Seguridad del Paciente , Monitoreo Fisiológico
2.
Gastrointest Endosc ; 97(4): 741-751.e1, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36400239

RESUMEN

BACKGROUND AND AIMS: Treatment strategies for small pancreatic neuroendocrine tumors (PNETs) <2 cm in size are still under debate. The feasibility and safety of EUS-guided ethanol ablation (EUS-EA) have been demonstrated. However, sample sizes in previous studies were small with no comparative studies on surgery. Therefore, we aimed to compare the safety and long-term outcomes of EUS-EA with those of surgery for the management of nonfunctioning small PNETs. METHODS: We retrospectively reviewed patients with PNETs who were managed by EUS-EA (from 2011 to 2018) and surgery (from 2000 to 2018) at Asan Medical Center. Propensity score matching (PSM) was performed to increase comparability. The primary outcome was early and late major adverse events (Clavien-Dindo grade ≥III) after treatment. Secondary outcomes were 10-year overall (OS) and disease-specific survival (DSS) rates, length of hospital stay, and development of endocrine pancreatic insufficiency. RESULTS: Of all patients, 97 and 188 patients were included in the EUS-EA and surgery groups, respectively. PSM created 89 matched pairs. EUS-EA was associated with a significantly lower rate of early major adverse events (0% vs 11.2%, P = .003). Late major adverse events occurred more frequently after surgery, with no significant difference between groups (3.4% vs 10.1%, P = .07). Both treatment modalities showed comparable 10-year OS and DSS rates. The length of hospital stay was significantly shorter in the EUS-EA group (4 days vs 14.1 days, P < .001), and endocrine pancreatic insufficiency was less common after EUS-EA than after surgery (33.3% vs 48.6%, P = .121). CONCLUSIONS: EUS-EA had fewer adverse events and a shorter hospital stay with similar OS and DSS rates compared with surgery, suggesting that EUS-EA may be a preferred alternative to surgical resection in selected patients with nonfunctioning small PNETs.


Asunto(s)
Tumores Neuroectodérmicos Primitivos , Tumores Neuroendocrinos , Neoplasias Pancreáticas , Humanos , Tumores Neuroendocrinos/cirugía , Estudios Retrospectivos , Puntaje de Propensión , Neoplasias Pancreáticas/cirugía , Neoplasias Pancreáticas/patología , Resultado del Tratamiento
3.
Nat Immunol ; 24(1): 148-161, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36577929

RESUMEN

Regulatory T (Treg) cells have an immunosuppressive function and highly express the immune checkpoint receptor PD-1 in the tumor microenvironment; however, the function of PD-1 in tumor-infiltrating (TI) Treg cells remains controversial. Here, we showed that conditional deletion of PD-1 in Treg cells delayed tumor progression. In Pdcd1fl/flFoxp3eGFP-Cre-ERT2(+/-) mice, in which both PD-1-expressing and PD-1-deficient Treg cells coexisted in the same tissue environment, conditional deletion of PD-1 in Treg cells resulted in impairment of the proliferative and suppressive capacity of TI Treg cells. PD-1 antibody therapy reduced the TI Treg cell numbers, but did not directly restore the cytokine production of TI CD8+ T cells in TC-1 lung cancer. Single-cell analysis indicated that PD-1 signaling promoted lipid metabolism, proliferation and suppressive pathways in TI Treg cells. These results suggest that PD-1 ablation or inhibition can enhance antitumor immunity by weakening Treg cell lineage stability and metabolic fitness in the tumor microenvironment.


Asunto(s)
Neoplasias , Linfocitos T Reguladores , Animales , Ratones , Linfocitos T CD8-positivos , Expresión Génica , Linfocitos Infiltrantes de Tumor , Neoplasias/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Microambiente Tumoral
4.
Kidney Int ; 103(2): 343-356, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36332729

RESUMEN

Current treatment strategies for autoimmune diseases may not sufficiently control aberrant metabolism in B-cells. To address this concern, we investigated a biguanide derivative, IM156, as a potential regulator for B-cell metabolism in vitro and in vivo on overactive B-cells stimulated by the pro-inflammatory receptor TLR-9 agonist CpG oligodeoxynucleotide, a mimic of viral/bacterial DNA. Using RNA sequencing, we analyzed the B-cell transcriptome expression, identifying the major molecular pathways affected by IM156 in vivo. We also evaluated the anti-inflammatory effects of IM156 in lupus-prone NZB/W F1 mice. CD19+B-cells exhibited higher mitochondrial mass and mitochondrial membrane potential compared to T-cells and were more susceptible to IM156-mediated oxidative phosphorylation inhibition. In vivo, IM156 inhibited mitochondrial oxidative phosphorylation, cell cycle progression, plasmablast differentiation, and activation marker levels in CpG oligodeoxynucleotide-stimulated mouse spleen B-cells. Interestingly, IM156 treatment significantly increased overall survival, reduced glomerulonephritis and inhibited B-cell activation in the NZB/W F1 mice. Thus, our data indicated that IM156 suppressed the mitochondrial membrane potentials of activated B-cells in mice, contributing to the mitigation of lupus activity. Hence, IM156 may represent a therapeutic alternative for autoimmune disease mediated by B-cell hyperactivity.


Asunto(s)
Enfermedades Autoinmunes , Lupus Eritematoso Sistémico , Ratones , Animales , Potencial de la Membrana Mitocondrial , Fosforilación Oxidativa , Lupus Eritematoso Sistémico/tratamiento farmacológico , Linfocitos B , Ratones Endogámicos NZB , Oligodesoxirribonucleótidos/farmacología
5.
Sci Total Environ ; 838(Pt 3): 156344, 2022 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-35654203

RESUMEN

Atmospheric volatile organic compounds (VOCs) in Seoul, the capital of South Korea, have attracted increased attention owing to their emission, secondary formation, and human health risk. In this study, we collected 24 hourly samples once a month at an urban site in Seoul for a year (a total of 288 samples) using a sequential tube sampler. Analysis results revealed that toluene (9.08 ± 8.99 µg/m3) exhibited the highest annual mean concentration, followed by ethyl acetate (5.55 ± 9.09 µg/m3), m,p-xylenes (2.79 ± 4.57 µg/m3), benzene (2.37 ± 1.55 µg/m3), ethylbenzene (1.81 ± 2.27 µg/m3), and o-xylene (0.91 ± 1.47 µg/m3), indicating that these compounds accounted for 77.8-85.6% of the seasonal mean concentrations of the total (Σ59) VOCs. The concentrations of the Σ59 VOCs were statistically higher in spring and winter than in summer and fall because of meteorological conditions, and the concentrations of individual VOCs were higher during the daytime than nighttime owing to higher human activities during the daytime. The conditional bivariate probability function and concentration weighted trajectory analysis results suggested that domestic effects (e.g., vehicular exhaust and solvents) exhibited a dominant effect on the presence of VOCs in Seoul, as well as long-range atmospheric transport of VOCs. Further, the most important secondary organic aerosol formation potential (SOAFP) compounds included benzene, toluene, ethylbenzene, and m,p,o-xylenes, and the total SOAFP of nine VOCs accounted for 5-29% of the seasonal mean PM2.5 concentrations. The cancer and non-cancer risks of the selected VOCs were below the tolerable (1 × 10-4) and acceptable (Hazard quotient: HQ < 1) levels, respectively. Overall, this study highlighted the feasibility of the sequential sampling of VOCs and hybrid receptor modeling to further understand the source-receptor relationship of VOCs.


Asunto(s)
Contaminantes Atmosféricos , Compuestos Orgánicos Volátiles , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Benceno/análisis , China , Monitoreo del Ambiente , Humanos , Seúl , Tolueno/análisis , Compuestos Orgánicos Volátiles/análisis , Xilenos/análisis
6.
Surg Endosc ; 36(4): 2445-2455, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34009477

RESUMEN

BACKGROUND: Owing to an increased number of colonoscopy screenings, the incidence of diagnosed rectal neuroendocrine tumors (NETs) has also increased. Tumor size is one of the most frequently regarded factors when selecting treatment; however, it may not be the determinant prognostic variable. We aimed to evaluate oncological outcomes according to the treatment modality based on the size of rectal NETs. METHODS: A retrospective analysis was performed on patients who were treated for rectal NETs between March 2000 and January 2016 at the Asan Medical Center, Seoul, Korea. Patients who underwent endoscopic removal, local surgical excision, and radical resection were included. The primary outcome was recurrence-free survival (RFS). Data were specified and analyzed following the 2019 World Health Organization classification (WHO). RESULTS: A total of 644 patients were categorized under three groups according to the treatment modality used: endoscopic removal (n = 567), surgical local excision (n = 56), and radical resection (n = 21). Of a total of 35 recurrences, 27 were local, whereas eight were distant. The RFS rate did not differ significantly between the treatment groups in the same tumor-size group ([Formula: see text]1 cm group: P = .636, 1-2 cm group: P = .160). For T1 tumors, RFS rate was not different between local excision and radical resection ([Formula: see text]1 cm group: P = .452, 1-2 cm group: P = .700). Depth of invasion, a high Ki-67 index, and margin involvement were confirmed as independent risk factors for recurrence. Among patients treated with endoscopic removal, endoscopic biopsy was a significant factor for worse RFS (P < .001), while tumor size did not affect the RFS. CONCLUSION: The current guideline recommends treatment options according to tumor size. However, more oncologically important prognostic factors include muscularis propria invasion and a higher Ki-67 index.


Asunto(s)
Tumores Neuroendocrinos , Neoplasias del Recto , Humanos , Antígeno Ki-67 , Tumores Neuroendocrinos/cirugía , Pronóstico , Neoplasias del Recto/cirugía , Estudios Retrospectivos
7.
Environ Pollut ; 294: 118644, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34875266

RESUMEN

Nitrated and oxygenated polycyclic aromatic hydrocarbons (NPAHs and OPAHs) are receiving attention because of their high toxicity compared with parent PAHs. However, the experimental data of their physicochemical properties has been limited. This study proposed the gas chromatographic retention time (GC-RT) technique as an effective alternative one to determine octanol-air partition coefficients (KOA) and sub-cooled liquid vapor pressures (PL) for 11 NPAHs, 10 OPAHs, and 19 parent PAHs. The slopes and intercepts of the linear regressions between temperature versus KOA and PL were provided and can be used to estimate KOA and PL for the 40 targeted compounds at any temperature. The internal energies of phase transfer (ΔUOA) and enthalpies of vaporization (ΔHL) for all targeted compounds were also calculated using the GC-RT technique. High-molecular-weight compounds may release or absorb higher heat energy to transform between different phases. NPAHs and OPAHs had a non-ideal solution behavior with activity in octanol (γoct) in the range of 19-53 and 18-1,078, respectively, which is larger than the unity threshold. A comparison among four groups of PAH derivatives showed that a functional group (nitro-, oxygen-, chloro-, and bromo-) in PAH derivatives increased γoct for corresponding parent PAHs by tens (mono-group) to hundreds of times (di-group). This study suggests that the GC-RT method is applicable for indirectly measuring the physicochemical properties of various groups of organic compounds.


Asunto(s)
Contaminantes Atmosféricos , Hidrocarburos Policíclicos Aromáticos , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Nitratos , Óxidos de Nitrógeno , Hidrocarburos Policíclicos Aromáticos/análisis
8.
Sci Total Environ ; 793: 148339, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34175601

RESUMEN

This study aims to investigate the spatial distribution of and temporal variation in the phase distribution, emission sources, and ecological risk of polycyclic aromatic hydrocarbons (PAHs) in runoff and in surface water mixed with runoff discharge. The samples were collected at semi-rural, residential, and industrial sites in Ulsan, South Korea, from April to October 2016. The industrial site had the highest PAH concentrations in the runoff and surface water due to the higher PAH levels found in the surrounding environmental media. The PAH phase distributions were relatively similar between the sampling sites, with dissolved PAHs (2- to 4-ring species) dominant. In July, the PAHs in the surface water were more commonly found in the dissolved phase due to the higher water temperature and dissolved organic carbon concentration. The emission sources for the PAHs were identified using principal component analysis (PCA), a dimension reduction technique, and the k-nearest neighbor (KNN) classifier, a supervised learning algorithm. It was determined that the PAHs in the runoff and surface water were likely to share similar petrogenic and pyrolysis sources for most of the sampling periods. The ecological risk of the surface water was 1.5-4.5 times lower after being mixed with runoff water, mainly due to dilution effects. The ecological risk for surface water was highest in July because of the higher PAH concentrations. This study contributes to the understanding of PAHs in runoff and in surface water affected by runoff discharge.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Sedimentos Geológicos , Hidrocarburos Policíclicos Aromáticos/análisis , República de Corea , Agua , Contaminantes Químicos del Agua/análisis
9.
Comput Struct Biotechnol J ; 19: 860-868, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33598101

RESUMEN

Regulatory T cells (Tregs) are enriched in the tumor microenvironment and play key roles in immune evasion of cancer cells. Cell surface markers specific for tumor-infiltrating Tregs (TI-Tregs) can be effectively targeted to enhance antitumor immunity and used for stratification of immunotherapy outcomes. Here, we present a systems biology approach to identify functional cell surface markers for TI-Tregs. We selected differentially expressed genes for surface proteins of TI-Tregs and compared these with other CD4+ T cells using bulk RNA-sequencing data from murine lung cancer models. Thereafter, we filtered for human orthologues with conserved expression in TI-Tregs using single-cell transcriptome data from patients with non-small cell lung cancer (NSCLC). To evaluate the functional importance of expression-based markers of TI-Tregs, we utilized network-based measure of context-associated centrality in a Treg-specific coregulatory network. We identified TNFRSF9 (also known as 4-1BB or CD137), a previously reported target for enhancing antitumor immunity, among the final candidates for TI-Treg markers with high functional importance score. We found that the low TNFRSF9 expression level in Tregs was associated with enhanced overall survival rate and response to anti-PD-1 immunotherapy in patients with NSCLC, proposing that TNFRSF9 promotes immune suppressive activity of Tregs in tumor. Collectively, these results demonstrated that integrative transcriptome and network analysis can facilitate the discovery of functional markers of tumor-specific immune cells to develop novel therapeutic targets and biomarkers for boosting cancer immunotherapy.

10.
Cancer Immunol Res ; 8(11): 1393-1406, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32878747

RESUMEN

Regulatory T cells (Treg) are enriched in the tumor microenvironment (TME) and suppress antitumor immunity; however, the molecular mechanism underlying the accumulation of Tregs in the TME is poorly understood. In various tumor models, tumor-infiltrating Tregs were highly enriched in the TME and had significantly higher expression of immune checkpoint molecules. To characterize tumor-infiltrating Tregs, we performed bulk RNA sequencing (RNA-seq) and found that proliferation-related genes, immune suppression-related genes, and cytokine/chemokine receptor genes were upregulated in tumor-infiltrating Tregs compared with tumor-infiltrating CD4+Foxp3- conventional T cells or splenic Tregs from the same tumor-bearing mice. Single-cell RNA-seq and T-cell receptor sequencing also revealed active proliferation of tumor infiltrating Tregs by clonal expansion. One of these genes, ST2, an IL33 receptor, was identified as a potential factor driving Treg accumulation in the TME. Indeed, IL33-directed ST2 signaling induced the preferential proliferation of tumor-infiltrating Tregs and enhanced tumor progression, whereas genetic deletion of ST2 in Tregs limited their TME accumulation and delayed tumor growth. These data demonstrated the IL33/ST2 axis in Tregs as one of the critical pathways for the preferential accumulation of Tregs in the TME and suggests that the IL33/ST2 axis may be a potential therapeutic target for cancer immunotherapy.


Asunto(s)
Inmunoterapia/métodos , Interleucina-33/metabolismo , Linfocitos T Reguladores/metabolismo , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Ratones , Transducción de Señal , Microambiente Tumoral
11.
Sci Rep ; 10(1): 9050, 2020 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-32493990

RESUMEN

Inhibition of immune checkpoint proteins like programmed death 1 (PD-1) is a promising therapeutic approach for several cancers, including non-small cell lung cancer (NSCLC). Although PD-1 ligand (PD-L1) expression is used to predict anti-PD-1 therapy responses in NSCLC, its accuracy is relatively less. Therefore, we sought to identify a more accurate predictive blood biomarker for evaluating anti-PD-1 response. We evaluated the frequencies of T cells, B cells, natural killer (NK) cells, polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs), mononuclear myeloid-derived suppressor cells (M-MDSCs), and Lox-1+ PMN-MDSCs in peripheral blood samples of 62 NSCLC patients before and after nivolumab treatment. Correlation of immune-cell population frequencies with treatment response, progression-free survival, and overall survival was also determined. After the first treatment, the median NK cell percentage was significantly higher in responders than in non-responders, while the median Lox-1+ PMN-MDSC percentage showed the opposite trend. NK cell frequencies significantly increased in responders but not in non-responders. NK cell frequency inversely correlated with that of Lox-1+ PMN-MDSCs after the first treatment cycle. The NK cell-to-Lox-1+ PMN-MDSC ratio (NMR) was significantly higher in responders than in non-responders. Patients with NMRs ≥ 5.75 after the first cycle had significantly higher objective response rates and longer progression-free and overall survival than those with NMRs <5.75. NMR shows promise as an early predictor of response to further anti-PD-1 therapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/inmunología , Células Asesinas Naturales/inmunología , Neoplasias Pulmonares/inmunología , Células Supresoras de Origen Mieloide/inmunología , Receptor de Muerte Celular Programada 1/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Linfocitos B/inmunología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Femenino , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Nivolumab/uso terapéutico , Supervivencia sin Progresión , Estudios Prospectivos , Linfocitos T/inmunología
12.
J Metab Bariatr Surg ; 9(1): 19-23, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36686894

RESUMEN

Portomesenteric vein thrombosis is an uncommon but potentially life-threatening complication associated with laparoscopic sleeve gastrectomy. We present the case of a 26-year-old male who underwent an uneventful laparoscopic sleeve gastrectomy and presented on postoperative day 14 with portomesenteric vein thrombosis. The patient was treated conservatively with IV heparinization, followed by an oral anticoagulant agent. He was discharged in stable condition without further problems. A high index of suspicion for the disease is required not to miss or delay the diagnosis of portomesenteric vein thrombosis which could lead to a fatal outcome. All patients should be screened beforehand for underlying hypercoagulability before surgery.

13.
J Immunother Cancer ; 7(1): 339, 2019 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-31801611

RESUMEN

BACKGROUND: Regulatory T (Treg) cells have an immunosuppressive function in cancer, but the underlying mechanism of immunosuppression in the tumor microenvironment (TME) is unclear. METHODS: We compared the phenotypes of T cell subsets, including Treg cells, obtained from peripheral blood, malignant effusion, and tumors of 103 cancer patients. Our primary focus was on the expression of immune checkpoint (IC)-molecules, such as programmed death (PD)-1, T-cell immunoglobulin and mucin-domain containing (TIM)-3, T cell Ig and ITIM domain (TIGIT), and cytotoxic T lymphocyte antigen (CTLA)-4, on Treg cells in paired lymphocytes from blood, peritumoral tissue, and tumors of 12 patients with lung cancer. To identify the immunosuppressive mechanisms acting on tumor-infiltrating Treg cells, we conducted immunosuppressive functional assays in a mouse model. RESULTS: CD8+, CD4+ T cells, and Treg cells exhibited a gradual upregulation of IC-molecules the closer they were to the tumor. Interestingly, PD-1 expression was more prominent in Treg cells than in conventional T (Tconv) cells. In lung cancer patients, higher levels of IC-molecules were expressed on Treg cells than on Tconv cells, and Treg cells were also more enriched in the tumor than in the peri-tumor and blood. In a mouse lung cancer model, IC-molecules were also preferentially upregulated on Treg cells, compared to Tconv cells. PD-1 showed the greatest increase on most cell types, especially Treg cells, and this increase occurred gradually over time after the cells entered the TME. PD-1 high-expressing tumor-infiltrating Treg cells displayed potent suppressive activity, which could be partially inhibited with a blocking anti-PD-1 antibody. CONCLUSIONS: We demonstrate that the TME confers a suppressive function on Treg cells by upregulating IC-molecule expression. Targeting IC-molecules, including PD-1, on Treg cells may be effective for cancer treatment.


Asunto(s)
Biomarcadores de Tumor , Inmunomodulación , Linfocitos T Reguladores/inmunología , Microambiente Tumoral/inmunología , Animales , Biopsia , Modelos Animales de Enfermedad , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Inmunofenotipificación , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Ratones , Ratones Noqueados , Estadificación de Neoplasias , Neoplasias/diagnóstico , Neoplasias/etiología , Neoplasias/metabolismo , Unión Proteica , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Linfocitos T Reguladores/metabolismo , Tomografía Computarizada por Rayos X , Microambiente Tumoral/genética , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Immune Netw ; 19(4): e25, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31501713

RESUMEN

CD80 is mainly expressed on Ag-presenting cells (APCs) as a costimulatory molecule but is also detected on T cells. However, the origin and physiological role of CD80 on CD8+ T cells remain unclear. In the present study, we demonstrated that effector and memory CD8+ T cells, but not naïve CD8+ T cells, displayed CD80 molecules on their surfaces after acute lymphocytic choriomeningitis virus infection. Using adoptive transfer of CD80-knockout (KO) CD8+ T cells into a wild type or CD80-KO recipient, we demonstrated that the effector CD8+ T cells displayed CD80 by both intrinsic expression and extrinsic acquisition, while memory CD8+ T cells displayed CD80 only by extrinsic acquisition. Interestingly, the extrinsic acquisition of CD80 by CD8+ T cells was observed only in the lymphoid organs but not in the periphery, indicating the trogocytosis of CD80 molecules via interaction between CD8+ T cells and APCs. We compared the recall immune responses by memory CD8+ T cells that either extrinsically acquired CD80 or were deficient in CD80, and found that CD80, presented by memory CD8+ T cells, played a role in limiting their expansion and IL-2 production upon exposure to secondary challenge. Our study presents the in vivo dynamics of the extrinsic acquisition of CD80 by Ag-specific CD8+ T cells and its role in the regulation of recall immune responses in memory CD8+ T cells.

15.
Mol Cells ; 42(8): 597-603, 2019 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-31387164

RESUMEN

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a core enzyme of the aerobic glycolytic pathway with versatile functions and is associated with cancer development. Recently, Kornberg et al . published the detailed correlation between GAPDH and di- or monomethyl fumarate (DMF or MMF), which are well-known GAPDH antagonists in the immune system. As an extension, herein, we report the crystal structure of MMF-bound human GAPDH at 2.29 Å. The MMF molecule is covalently linked to the catalytic Cys152 of human GAPDH, and inhibits the catalytic activity of the residue and dramatically reduces the enzymatic activity of GAPDH. Structural comparisons between NAD+bound GAPDH and MMF-bound GAPDH revealed that the covalently linked MMF can block the binding of the NAD+ cosubstrate due to steric hindrance of the nicotinamide portion of the NAD+ molecule, illuminating the specific mechanism by which MMF inhibits GAPDH. Our data provide insights into GAPDH antagonist development for GAPDH-mediated disease treatment.


Asunto(s)
Fumaratos/química , Gliceraldehído-3-Fosfato Deshidrogenasas/química , Maleatos/química , Dominio Catalítico , Proliferación Celular/efectos de los fármacos , Fumaratos/farmacología , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Humanos , Maleatos/farmacología , Unión Proteica , Linfocitos T/citología , Linfocitos T/efectos de los fármacos
16.
Immune Netw ; 19(2): e11, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31089438

RESUMEN

During virus infection, T cells must be adapted to activation and lineage differentiation states via metabolic reprogramming. Whereas effector CD8+ T cells preferentially use glycolysis for their rapid proliferation, memory CD8+ T cells utilize oxidative phosphorylation for their homeostatic maintenance. Particularly, enhanced AMP-activated protein kinase (AMPK) activity promotes the memory T cell response through different pathways. However, the level of AMPK activation required for optimal memory T cell differentiation remains unclear. A new metformin derivative, IM156, formerly known as HL156A, has been reported to ameliorate various types of fibrosis and inhibit in vitro and in vivo tumors by inducing AMPK activation more potently than metformin. Here, we evaluated the in vivo effects of IM156 on antigen-specific CD8+ T cells during their effector and memory differentiation after acute lymphocytic choriomeningitis virus infection. Unexpectedly, our results showed that in vivo treatment of IM156 exacerbated the memory differentiation of virus-specific CD8+ T cells, resulting in an increase in short-lived effector cells but decrease in memory precursor effector cells. Thus, IM156 treatment impaired the function of virus-specific memory CD8+ T cells, indicating that excessive AMPK activation weakens memory T cell differentiation, thereby suppressing recall immune responses. This study suggests that metabolic reprogramming of antigen-specific CD8+ T cells by regulating the AMPK pathway should be carefully performed and managed to improve the efficacy of T cell vaccine.

18.
J Immunol ; 194(12): 5801-11, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25934860

RESUMEN

Regulatory T (Treg) cells act as terminators of T cell immuniy during acute phase of viral infection; however, their role and suppressive mechanism in chronic viral infection are not completely understood. In this study, we compared the phenotype and function of Treg cells during acute or chronic infection with lymphocytic choriomeningitis virus. Chronic infection, unlike acute infection, led to a large expansion of Treg cells and their upregulation of programmed death-1 (PD-1). Treg cells from chronically infected mice (chronic Treg cells) displayed greater suppressive capacity for inhibiting both CD8(+) and CD4(+) T cell proliferation and subsequent cytokine production than those from naive or acutely infected mice. A contact between Treg and CD8(+) T cells was necessary for the potent suppression of CD8(+) T cell immune response. More importantly, the suppression required cell-specific expression and interaction of PD-1 on chronic Treg cells and PD-1 ligand on CD8(+) T cells. Our study defines PD-1 upregulated on Treg cells and its interaction with PD-1 ligand on effector T cells as one cause for the potent T cell suppression and proposes the role of PD-1 on Treg cells, in addition to that on exhausted T cells, during chronic viral infection.


Asunto(s)
Antígeno B7-H1/genética , Inmunomodulación , Receptor de Muerte Celular Programada 1/genética , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Virosis/genética , Virosis/inmunología , Animales , Antígenos CD/metabolismo , Antígeno B7-H1/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Comunicación Celular/inmunología , Enfermedad Crónica , Modelos Animales de Enfermedad , Femenino , Expresión Génica , Proteína Relacionada con TNFR Inducida por Glucocorticoide/metabolismo , Inmunofenotipificación , Cadenas alfa de Integrinas/metabolismo , Activación de Linfocitos/inmunología , Recuento de Linfocitos , Depleción Linfocítica , Ratones , Ratones Noqueados , Fenotipo , Receptor de Muerte Celular Programada 1/metabolismo , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo
19.
Oncotarget ; 5(9): 2761-77, 2014 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-24811731

RESUMEN

Tumor blood vessels are leaky and immature, which causes inadequate blood supply to tumor tissues resulting in hypoxic microenvironment and promotes metastasis. Here we have explored tumor vessel modulating activity of Sac-1004, a recently developed molecule in our lab, which directly potentiates VE-cadherin-mediated endothelial cell junction. Sac-1004 could enhance vascular junction integrity in tumor vessels and thereby inhibit vascular leakage and enhance vascular perfusion. Improved perfusion enabled Sac-1004 to have synergistic anti-tumor effect on cisplatin-mediated apoptosis of tumor cells. Interestingly, characteristics of normalized blood vessels namely reduced hypoxia, improved pericyte coverage and decreased basement membrane thickness were readily observed in tumors treated with Sac-1004. Remarkably, Sac-1004 was also able to inhibit lung and lymph node metastasis in MMTV and B16BL6 tumor models. This was in correlation with a reduction in epithelial-to-mesenchymal transition of tumor cells with considerable diminution in expression of related transcription factors. Moreover, cancer stem cell population dropped substantially in Sac-1004 treated tumor tissues. Taken together, our results showed that direct restoration of vascular junction could be a significant strategy to induce normalization of tumor blood vessels and reduce metastasis.


Asunto(s)
Antígenos CD/metabolismo , Cadherinas/metabolismo , Carcinoma Pulmonar de Lewis/prevención & control , Endotelio Vascular/efectos de los fármacos , Neoplasias Pulmonares/prevención & control , Melanoma Experimental/prevención & control , Neovascularización Patológica/prevención & control , Saponinas/farmacología , Animales , Antígenos CD/genética , Apoptosis/efectos de los fármacos , Western Blotting , Cadherinas/genética , Carcinoma Pulmonar de Lewis/irrigación sanguínea , Carcinoma Pulmonar de Lewis/metabolismo , Carcinoma Pulmonar de Lewis/patología , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Retinopatía Diabética/metabolismo , Retinopatía Diabética/patología , Retinopatía Diabética/prevención & control , Endotelio Vascular/metabolismo , Endotelio Vascular/patología , Transición Epitelial-Mesenquimal/efectos de los fármacos , Células HeLa , Humanos , Técnicas para Inmunoenzimas , Neoplasias Pulmonares/irrigación sanguínea , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundario , Metástasis Linfática , Células MCF-7 , Masculino , Melanoma Experimental/irrigación sanguínea , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Ratones , Ratones Endogámicos C57BL , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
20.
Ann Occup Environ Med ; 25(1): 29, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-24472303

RESUMEN

OBJECTIVE: This study aims to investigate the relationship between waist circumference and work-related injury in reference to the fourth Korea National Health and Nutrition Examination Survey. METHODS: By analyzing data from the fourth Korea National Health and Nutrition Examination Survey conducted from 2007 to 2009, we estimated the rate of injury experience according to socioeconomic status, including occupational property, of 8,261 subjects. We performed logistic regression analysis with work-related injury experience rate as dependent variable and waist circumference as an independent variable, Odds ratios (OR) were calculated, which reflect the likelihood of work-related injury experience rate, and 95% confidence interval (95% CI) while controlling for relevant covariates with stratifying by sex, age, nature of injury, site of injury and occupational group. RESULTS: Among 797 persons who had injury experience over the past 1 year, 293 persons (36.8%) had work-related injury experience. After adjusting the confounding variables, the work-related injury was related to abnormal waist circumference (OR = 1.35; 95% CI: 1.02 ~ 1.78). In subgroups, ORs were higher in men (OR = 1.42; 95% CI: 1.02 ~ 1.98), professional, manager, and administrator (OR = 2.41; 95% CI: 1.10 ~ 5.28). Higher rate of injuries were noted in back and waist (OR = 2.92; 95% CI: 1.49 ~ 5.73), and transport accident had increased risk (OR = 1.60; 95% CI: 1.13 ~ 2.28). CONCLUSIONS: Work-related injury rate differed depending on the waist circumference. The abdominal obesity was associated with higher risk of work-related injury. This study would be useful in selecting appropriate priorities for work-related injury management in Korea.

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