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1.
Proc Natl Acad Sci U S A ; 120(33): e2300036120, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37549292

RESUMEN

While the world is rapidly transforming into a superaging society, pharmaceutical approaches to treat sarcopenia have hitherto not been successful due to their insufficient efficacy and failure to specifically target skeletal muscle cells (skMCs). Although electrical stimulation (ES) is emerging as an alternative intervention, its efficacy toward treating sarcopenia remains unexplored. In this study, we demonstrate a silver electroceutical technology with the potential to treat sarcopenia. First, we developed a high-throughput ES screening platform that can simultaneously stimulate 15 independent conditions, while utilizing only a small number of human-derived primary aged/young skMCs (hAskMC/hYskMC). The in vitro screening showed that specific ES conditions induced hypertrophy and rejuvenation in hAskMCs, and the optimal ES frequency in hAskMCs was different from that in hYskMCs. When applied to aged mice in vivo, specific ES conditions improved the prevalence and thickness of Type IIA fibers, along with biomechanical attributes, toward a younger skMC phenotype. This study is expected to pave the way toward an electroceutical treatment for sarcopenia with minimal side effects and help realize personalized bioelectronic medicine.


Asunto(s)
Sarcopenia , Animales , Humanos , Ratones , Fibras Musculares Esqueléticas , Músculo Esquelético/fisiología , Fenotipo , Sarcopenia/terapia , Plata
2.
Anal Chem ; 95(26): 9949-9958, 2023 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-37279022

RESUMEN

Natural killer (NK) cells are a part of the innate immune system, providing the first line of defense against cancer cells and pathogens at an early stage. Hence, they are attracting attention as a valuable resource for allogeneic cell immunotherapy. However, NK cells exist with limited proportion in blood, and obtaining sufficient clinical-grade NK cells with highly viable and minimal stress is critical for successful immune cell therapy. Conventional purification methods via immunoaffinity or density gradient centrifugation had several limitations in yield, purity, and cellular stress, which might cause an increased risk for graft versus host disease and reduced efficacy due to NK cell malfunction, exhaustion, and apoptosis. Moreover, reducing the variations of isolation performance caused by the manual process is another unmet need for uniform quality of the living drug. Here, an automated system using an NK disc (NKD) based on continuous centrifugal microfluidics (CCM) technology was developed to isolate NK cells from whole blood with high yield, purity, reproducibility, and low stress. The CCM technology, which operates fluidic manipulation under disc rotation, enabled precise extraction of the ultra-thin target fluid layer generated by blood centrifugation. Compared to the conventional manual method, the CCM-NKD isolated NK cells with higher yield (recovery rate) and purity, while maintaining better reproducibility. Furthermore, since the CCM-NKD maintained substantially milder centrifugation conditions (120 ×g for 10 min) compared to the conventional approach (1200 ×g for 20 min), it showed reduced cellular stress and increased antioxidant capacity in the isolated NK cells. Based on the results, the CCM-NKD is expected to be a useful tool to provide highly intact and viable cell weapons for successful immune cell therapy.


Asunto(s)
Células Asesinas Naturales , Microfluídica , Reproducibilidad de los Resultados , Inmunoterapia
3.
J Korean Med Sci ; 38(33): e258, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37605497

RESUMEN

BACKGROUND: This study aimed to identify the specific T cell co-stimulatory and co-inhibitory factors that play prognostic roles in patients with glioblastoma. Additionally, the unique histone H3 modification enzymes that regulate the expression levels of these specific co-stimulatory and co-inhibitory factors were investigated. METHODS: The medical records of 84 patients newly diagnosed with glioblastoma at our institution from January 2006 to December 2020 were retrospectively reviewed. Immunohistochemical (IHC) staining for T cell co-stimulatory factors (CD27, CD28, CD137, OX40, and ICOS), T cell co-inhibitory factors (CTLA4, PD1, PD-L1, TIM3, and CD200R), and histone H3 lysine modification enzymes (MLL4, RIZ, EZH1, NSD2, KDM5c, JMJD1a, UTX, and JMJD5) was performed on archived paraffin-embedded tissues obtained by biopsy or resection. Quantitative real time-polymerase chain reaction (qRT-PCR) was performed for specific factors, which demonstrated causal relationships, in order to validate the findings of the IHC examinations. RESULTS: The mean follow-up duration was 27.5 months (range, 4.1-43.5 months). During this period, 76 patients (90.5%) died, and the mean OS was 19.4 months (95% confidence interval, 16.3-20.9 months). Linear positive correlations were observed between the expression levels of CD28 and JMJD1a (R2 linear = 0.982) and those of CD137 and UTX (R2 linear = 1.528). Alternatively, significant negative correlations were observed between the expression levels of CTLA4 and RIZ (R2 linear = -1.746) and those of PD-L1 and EZH1 (R2 linear = -2.118); these relationships were confirmed by qRT-PCR. In the multivariate analysis, increased expression levels of CD28 (P = 0.042), and CD137 (P = 0.009), and decreased expression levels of CTLA4 (P = 0.003), PD-L1 (P = 0.020), and EZH1 (P = 0.040) were significantly associated with longer survival. CONCLUSION: These findings suggest that the expression of certain T cell co-stimulatory factors, such as CD28 and CD 137, and co-inhibitory factors, such as CTLA4 and PD-L1 are associated with prognosis of glioblastoma patients.


Asunto(s)
Glioblastoma , Histonas , Humanos , Antígeno CTLA-4/genética , Antígeno B7-H1 , Lisina , Pronóstico , Antígenos CD28 , Glioblastoma/diagnóstico , Glioblastoma/genética , Epigénesis Genética , Estudios Retrospectivos , Linfocitos T
4.
Cytokine ; 126: 154863, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31629112

RESUMEN

Adiponectin (Ad) is a representative adipocytokine that regulates energy homeostasis including glucose transport and lipid oxidation through activation of AMP-activated protein kinase (AMPK) pathways. Plasma levels of Ad are reduced in obesity, which contributes to type 2 diabetes. Therefore, agents that activate the Ad signaling pathway could ameliorate metabolic diseases such as type 2 diabetes. Here, we report the identification of a high-affinitive agonist antibody against Ad receptors. The antibody was selected by using phage display of human combinatorial antibody libraries. The selected antibody induced phosphorylation of the acetyl-CoA carboxylase (ACC) and AMPK in skeletal muscle cells and stimulated glucose uptake and fatty-acid oxidation (FAO) in myotubes. In addition, the antibody significantly lowered blood glucose levels during a glucose challenge in normal mice as well as basal blood glucose levels in a type 2 diabetic mouse model. Taken together, these results suggest that the agonist antibody could be a promising therapeutic agent for the treatment of metabolic syndrome such as type 2 diabetes.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Ácidos Grasos/metabolismo , Glucosa/metabolismo , Receptores de Adiponectina/agonistas , Receptores de Adiponectina/inmunología , Acetil-CoA Carboxilasa/metabolismo , Adiponectina/metabolismo , Animales , Glucemia/metabolismo , Línea Celular , Diabetes Mellitus Tipo 2/metabolismo , Técnicas de Silenciamiento del Gen , Glucosa/farmacología , Humanos , Metabolismo de los Lípidos , Masculino , Ratones , Ratones Endogámicos C57BL , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , FN-kappa B/metabolismo , Oxidación-Reducción , Fosforilación , ARN Interferente Pequeño , Receptores de Adiponectina/genética , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética
5.
Anal Chem ; 91(22): 14214-14219, 2019 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-31631648

RESUMEN

Pipetting techniques play a crucial role in obtaining reproducible and reliable results, especially when seeding cells on small target areas, such as on microarrays, biochips or microfabricated cell culture systems. For very rare cells, such as human primary skeletal muscle cells (skMCs), manual (freehand) cell seeding techniques invariably result in nonuniform cell spreading and heterogeneous cell densities, giving rise to undesirable variations in myogenesis and differentiation. To prevent such technique-dependent variation, we have designed and fabricated a simple, low-cost pipet guidance device (PGD), and holder that works with hand-held pipettes. This work validates the accuracy and reproducibility of the PGD platform and compares its effectiveness with manual and robotic seeding techniques. The PGD system ensures reproducibility of cell seeding, comparable to that of more expensive robotic dispensing systems, resulting in a high degree of cell uniformity and homogeneous cell densities, while also enabling cell community studies. As compared to freehand pipetting, PGD-assisted seeding of C2C12 mouse myoblasts showed 5.3 times more myotube formation and likewise myotubes derived from PGD-seeded human primary skMCs were 3.6 times thicker and 2.2 times longer. These results show that this novel, yet simple PGD-assisted pipetting technique provides precise cell seeding on small targets, ensuring reproducible and reliable high-throughput cell assays.


Asunto(s)
Técnicas de Cultivo de Célula/instrumentación , Músculo Esquelético/citología , Análisis de Matrices Tisulares/instrumentación , Recuento de Células , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Diseño de Equipo , Humanos , Análisis por Micromatrices
6.
Anal Chem ; 90(4): 2534-2541, 2018 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-29365265

RESUMEN

As paper-based diagnostics has become predominantly driven by more advanced microfluidic technology, many of the research efforts are still focused on developing reliable and versatile fluidic control devices, apart from improving sensitivity and reproducibility. In this work, we introduce a novel and robust paper fluidic control system enabling versatile fluidic control. The system comprises a linear push-pull solenoid and an Arduino Uno microcontroller. The precisely controlled pressure exerted on the paper stops the flow. We first determined the stroke distance of the solenoid to obtain a constant pressure while examining the fluidic time delay as a function of the pressure. Results showed that strips of grade 1 chromatography paper had superior reproducibility in fluid transport. Next, we characterized the reproducibility of the fluidic velocity which depends on the type and grade of paper used. As such, we were able to control the flow velocity on the paper and also achieve a complete stop of flow with a pressure over 2.0 MPa. Notably, after the actuation of the pressure driven valve (PDV), the previously pressed area regained its original flow properties. This means that, even on a previously pressed area, multiple valve operations can be successfully conducted. To the best of our knowledge, this is the first demonstration of an active and repetitive valve operation in paper microfluidics. As a proof of concept, we have chosen to perform a multistep detection system in the form of an enzyme-linked immunosorbent assay with mouse IgG as the target analyte.

7.
Cytokine ; 110: 397-403, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29921484

RESUMEN

Interleukin-5 (IL-5) is best known as key regulator in eosinophil-associated diseases such as asthma. While a connection to vascular changes in eosinophil-associated lung diseases is still elusive, recent evidence suggests that IL-5 may have an atheroprotective role. Here, we report an unexpected anti-angiogenic potential of IL-5 on vascular endothelial cells in vitro. IL-5 significantly inhibited fundamental functions of human lung microvascular endothelial cells (HMVEC-L) in vessel formation including VEGF-induced endothelial cell proliferation, migration and tube formation. Knockdown (KD) of STAT5 abolished the direct anti-angiogenic effect of IL-5 on VEGF-induced endothelial cell proliferation, migration and tube formation.


Asunto(s)
Interleucina-5/metabolismo , Neovascularización Patológica/metabolismo , Factor de Transcripción STAT5/metabolismo , Transducción de Señal/fisiología , Proteínas Supresoras de Tumor/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Inhibidores de la Angiogénesis/metabolismo , Movimiento Celular/fisiología , Proliferación Celular/fisiología , Células Cultivadas , Células Endoteliales/metabolismo , Endotelio Vascular/metabolismo , Humanos
8.
Int J Syst Evol Microbiol ; 67(4): 845-850, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27902288

RESUMEN

A Gram-stain-negative, strictly aerobic, rod-shaped bacterium, designated W1-2-1T, was isolated from tap water in South Korea. The strain was characterized by a polyphasic approach to clarify its taxonomic position. Strain W1-2-1T grew at 18-42 °C and at pH 6.0-10.0 on R2A medium. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the isolate belongs to the genus Sphingomonas and is most closely related to the Sphingomonas oligophenolica JCM 12082T (97.2 % similarity), Sphingomonas asaccharolyticaNBRC 15499T (96.8 %), Sphingomonas desiccabilis CP1DT (96.8 %), Sphingomonas pruniNBRC 15498T (96.8 %), Sphingomonas hankookensis ODN7T (96.4 %) and Sphingomonas yabuuchiae DSM 14562T (95.8 %). Chemotaxonomic data [major ubiquinone - Q10, major polyamine - homospermidine, major fatty acids - summed feature 8 (C18  : 1ω7c/ω6c), C16 : 0 and C14 : 0 2-OH and presence of sphingoglycolipid] supported the affiliation of the strain to the genus Sphingomonas. The G+C content of genomic DNA was 67.1 mol%. However, low level of DNA-DNA relatedness value between strain W1-2-1T and S. oligophenolica JCM 12082T and the results of physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain W1-2-1T from other Sphingomonas species with validly published names. Therefore, the isolate represents a novel species, for which the name Sphingomonas aquatica sp. nov. (type strain W1-2-1T=KACC 18309T=LMG 28596T) is proposed.


Asunto(s)
Agua Potable/microbiología , Filogenia , Sphingomonas/clasificación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Espermidina/química , Sphingomonas/genética , Sphingomonas/aislamiento & purificación , Ubiquinona/análogos & derivados , Ubiquinona/química
9.
Gen Physiol Biophys ; 36(1): 31-39, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27901471

RESUMEN

Esculetin, a coumarin derivative, is a phenolic compound isolated from Artemisia capillaris, Citrus limonia, and Euphorbia lathyris. Although it has been reported to have anti-inflammatory, anti-oxidant, and anti-proliferative activities in several human cancers, its anti-proliferative activity against non-small-cell lung carcinoma (NSCLC) and the molecular mechanisms involved have not been adequately elucidated. In this study, we used two NSCLC cell lines (NCI-H358 and NCI-H1299) to investigate the anti-proliferative activity and apoptotic effect of esculetin. Our data showed that esculetin-treated cells exhibited reduced proliferation and apoptotic cell morphologies. Intriguingly, the transcription factor specificity protein 1 (Sp1) was significantly suppressed by esculetin in a dose- and time-dependent manner. Furthermore, the levels of p27 and p21, two key regulators of the cell cycle, were up-regulated by the esculetin-mediated down-regulation of Sp1; the level of a third cell-cycle regulator, survivin, was decreased, resulting in caspase-dependent apoptosis. Therefore, we conclude that esculetin could be a potent anti-proliferative agent in patients with NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Neoplasias Pulmonares/metabolismo , Factor de Transcripción Sp1/metabolismo , Umbeliferonas/farmacología , Antineoplásicos/farmacología , Antioxidantes/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo/efectos de los fármacos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología
10.
Arch Microbiol ; 198(8): 767-71, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27177900

RESUMEN

A Gram reaction-negative, strictly aerobic, non-motile, translucent and rod-shaped bacterium (designated W1-2-4(T)) isolated from tap water was characterized by a polyphasic approach to clarify its taxonomic position. Strain W1-2-4(T) was observed to grow optimally at 25-30 °C and at pH 6.5 on nutrient agar. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain W1-2-4(T) belongs to the genus Sphingomonas and is most closely related to the Sphingomonas fennica K101(T) (95.3 % similarity). The G+C content of genomic DNA was 67.1 mol%. Chemotaxonomic data [major ubiquinone-Q-10, major polyamine-homospermidine, major fatty acids-summed feature 8 (comprising C18:1 ω7c/ω6c), C16:0 and C14:0 2OH] supported the affiliation of strain W1-2-4(T) to the genus Sphingomonas. Strain W1-2-4(T) could be differentiated genotypically and phenotypically from the recognized species of the genus Sphingomonas. The novel isolate therefore represents a novel species, for which the name Sphingomonas hankyongensis sp. nov. is proposed, with the type strain W1-2-4(T) (=KACC 18308(T) = LMG 28595(T)).


Asunto(s)
Agua Potable/microbiología , Sphingomonas/clasificación , Sphingomonas/aislamiento & purificación , Técnicas de Tipificación Bacteriana , Composición de Base/genética , ADN Bacteriano/genética , Ácidos Grasos/análisis , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Sphingomonas/genética , Ubiquinona/metabolismo , Microbiología del Agua
11.
Int J Syst Evol Microbiol ; 66(3): 1125x-1130, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26669622

RESUMEN

A Gram-stain-negative, rod-shaped, non-spore-forming, oxidase and catalase-positive, strictly aerobic bacterium, designated strain Gsoil 524T, was isolated from the soil of a ginseng field and subjected to polyphasic taxonomic analysis. Phylogenetic analysis, based on the 16S rRNA gene sequence, placed Gsoil 524T in a distinct lineage in the family Sphingobacteriaceae, sharing 87.2-88.0 % sequence similarity with members of the closely related genera Pedobacter, Mucilaginibacter and Solitalea. Strain Gsoil 524T contained MK-7 as the predominant quinone, and iso-C15 : 0, iso-C17 : 0 3-OH, summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 1ω5c as the major fatty acids. Strain Gsoil 524T could be distinguished from the other members of the family Sphingobacteriaceae by a number of chemotaxonomic and phenotypic characteristics. The major polar lipids in strain Gsoil 524T were phosphatidylethanolamine and two unidentified polar lipids. Compared with the standard and reference strains unidentified sphingolipid was also found. Based on this polyphasic taxonomic analysis, strain Gsoil 524T represents a novel species within a novel genus, for which the name Anseongella ginsenosidimutans gen. nov., sp. nov. is proposed. The type strain of Anseongella ginsenosidimutans is Gsoil 524T ( = KACC 14636T = KCTC 22261T = LMG 24494T).

12.
Asian-Australas J Anim Sci ; 29(8): 1197-206, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27165017

RESUMEN

Adipose tissue in the loin muscle area of beef cattle as a marbling factor is directly associated with beef quality. To elucidate whether properties of proteins involved in depot specific adipose tissue were sex-dependent, we analyzed protein expression of intramuscular adipose tissue (IMAT) and omental adipose tissue (OMAT) from Hanwoo cows, steers, and bulls of Korean native beef cattle by liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomic analysis, quantitative polymerase chain reaction (PCR) and western blot analysis. Two different adipose depots (i.e. intramuscular and omental) were collected from cows (n = 7), steers (n = 7), or bulls (n = 7). LC-MS/MS revealed a total of 55 and 35 proteins in IMAT and OMAT, respectively. Of the 55 proteins identified, 44, 40, and 42 proteins were confirmed to be differentially expressed in IMAT of cows, steers, and bulls, respectively. In OMAT of cows, steers, and bulls, 33, 33, and 22 were confirmed to be differentially expressed, respectively. Tropomyosin (TPM) 1, TPM 2, and TPM3 were subjected to verification by quantitative PCR and western blot analysis in IMAT and OMAT of Hanwoo cows, steers, and bulls as key factors closely associated with muscle development. Both mRNA levels and protein levels of TPM1, TPM2, and TPM3 in IMAT were lower in bulls compared to in cows or steers suggesting that they were positively correlated with marbling score and quality grade. Our results may aid the regulation of marbling development and improvement of meat quality grades in beef cattle.

13.
Asian-Australas J Anim Sci ; 29(11): 1653-1663, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27165031

RESUMEN

Meat quality is a complex trait influenced by many factors, including genetics, nutrition, feeding environment, animal handling, and their interactions. To elucidate relevant factors affecting pork quality associated with oxidative stress and muscle development, we analyzed protein expression in high quality longissimus dorsi muscles (HQLD) and low quality longissimus dorsi muscles (LQLD) from Duroc pigs by liquid chromatographytandem mass spectrometry (LC-MS/MS)-based proteomic analysis. Between HQLD (n = 20) and LQLD (n = 20) Duroc pigs, 24 differentially expressed proteins were identified by LC-MS/MS. A total of 10 and 14 proteins were highly expressed in HQLD and LQLD, respectively. The 24 proteins have putative functions in the following seven categories: catalytic activity (31%), ATPase activity (19%), oxidoreductase activity (13%), cytoskeletal protein binding (13%), actin binding (12%), calcium ion binding (6%), and structural constituent of muscle (6%). Silver-stained image analysis revealed significant differential expression of lactate dehydrogenase A (LDHA) between HQLD and LQLD Duroc pigs. LDHA was subjected to in vitro study of myogenesis under oxidative stress conditions and LDH activity assay to verification its role in oxidative stress. No significant difference of mRNA expression level of LDHA was found between normal and oxidative stress condition. However, LDH activity was significantly higher under oxidative stress condition than at normal condition using in vitro model of myogenesis. The highly expressed LDHA was positively correlated with LQLD. Moreover, LDHA activity increased by oxidative stress was reduced by antioxidant resveratrol. This paper emphasizes the importance of differential expression patterns of proteins and their interaction for the development of meat quality traits. Our proteome data provides valuable information on important factors which might aid in the regulation of muscle development and the improvement of meat quality in longissimus dorsi muscles of Duroc pigs under oxidative stress conditions.

14.
Anal Chem ; 87(19): 9584-8, 2015 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-26322520

RESUMEN

To precisely purify and study aged (senescent) cells, we have designed, fabricated, and demonstrated a novel diamond-structure (DS) microfluidic filter. Nonuniform flow velocities within the microfilter channel can compromise microfluidic filter performance, but with this new diamond structure, further optimized via simulation, we achieve a uniform microfilter flow field, improving the throughput of size-based separation of senescent cells, as obtained by 39-passaged human dermal fibroblasts. After separating these aged cells into two groups, consisting of large- and small-sized cells, we assessed senescence by measuring lipofuscin accumulation and ß-galactosidase activity. Our results reveal that even though these senescent cells had been equivalently passaged in culture, a high degree of size distribution and senescent phenotype heterogeneity was observed. In particular, the smaller-sized cells tended to express a younger phenotype while the larger aged cells demonstrated an older phenotype. We suggest that size-based separation of senescent cells, subtyped into small- and large-sized cohorts, offers an alternative method to purify such aged cells, thereby enabling more precise study of the mechanisms of aging, autophagy impairment, and rejuvenation.


Asunto(s)
Separación Celular , Senescencia Celular , Técnicas Analíticas Microfluídicas , Separación Celular/instrumentación , Células Cultivadas , Niño , Fibroblastos/citología , Humanos , Masculino , Técnicas Analíticas Microfluídicas/instrumentación , Tamaño de la Partícula , Piel/citología , Propiedades de Superficie
15.
Anal Chem ; 86(8): 3735-42, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24641782

RESUMEN

Full automation with high purity for circulating tumor cell (CTC) isolation has been regarded as a key goal to make CTC analysis a "bench-to-bedside" technology. Here, we have developed a novel centrifugal microfluidic platform that can isolate the rare cells from a large volume of whole blood. To isolate CTCs from whole blood, we introduce a disc device having the biggest sample capacity as well as manipulating blood cells for the first time. The fully automated disc platform could handle 5 mL of blood by designing the blood chamber having a triangular obstacle structure (TOS) with lateral direction. To guarantee high purity that enables molecular analysis with the rare cells, CTCs were bound to the microbeads covered with anti-EpCAM to discriminate density between CTCs and blood cells and the CTCs being heavier than blood cells were only settled under a density gradient medium (DGM) layer. To understand the movement of CTCs under centrifugal force, we performed computational fluid dynamics simulation and found that their major trajectories were the boundary walls of the DGM chamber, thereby optimizing the chamber design. After whole blood was inserted into the blood chamber of the disc platform, size- and density-amplified cancer cells were isolated within 78 min, with minimal contamination as much as approximately 12 leukocytes per milliliter. As a model of molecular analysis toward personalized cancer treatment, we performed epidermal growth factor receptor (EGFR) mutation analysis with HCC827 lung cancer cells and the isolated cells were then successfully detected for the mutation by PCR clamping and direct sequencing.


Asunto(s)
Separación Celular/instrumentación , Dispositivos Laboratorio en un Chip , Células Neoplásicas Circulantes/patología , Automatización , Células Sanguíneas , Línea Celular Tumoral , Centrifugación por Gradiente de Densidad , Análisis Mutacional de ADN , Receptores ErbB/genética , Humanos , Microfluídica , Reacción en Cadena de la Polimerasa , Medicina de Precisión
16.
Small ; 10(20): 4123-9, 2014 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-24975884

RESUMEN

Smart microfluidic pipette tip: A microfluidic method for removing cells and recovering liquid medium is presented and applied for blood cell rejection and cytotoxicity assay. This method enables continuous cell rejection by manual operation, potentially providing the means for rapid, inexpensive sample preparation for personalized diagnostics and mobile laboratory.


Asunto(s)
Microfluídica/instrumentación , Eritrocitos , Humanos
17.
Biomater Res ; 28: 0012, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38560578

RESUMEN

Non-biodegradable implants have undergone extensive investigation as drug delivery devices to enable advanced healthcare toward personalized medicine. However, fibroblast encapsulation is one of the major challenges in all non-biodegradable implants, besides other challenges such as high initial burst, risk of membrane rupture, high onset time, non-conformal contact with tissues, and tissue damage. To tackle such challenges, we propose a novel ultrasoft and flexible balloon-type drug delivery device for unidirectional and long-term controlled release. The ultrasoft balloon-type device (USBD) was fabricated by using selective bonding between 2 polydimethylsiloxane (PDMS) membranes and injecting a fluid into the non-bonded area between them. The balloon acted as a reservoir containing a liquid drug, and at the same time, the membrane of the balloon itself acted as the pathway for release based on diffusion. The release was modulated by tuning the thickness and composition of the PDMS membrane. Regardless of the thickness and composition, all devices exhibited zero-order release behavior. The longest zero-order release and nearly zero-order release were achieved for 30 days and 58 days at a release rate of 1.16 µg/day and 1.68 µg/day, respectively. In vivo evaluation was performed for 35 days in living rats, where the USBD maintained zero-order and nearly zero-order release for 28 days and 35 days, respectively. Thanks to the employment of ultrasoft and flexible membranes and device design, the USBD could achieve minimal tissue damage and foreign body responses. It is expected that the proposed device may provide a novel approach for long-term drug delivery with new therapeutic modalities.

18.
Small ; 9(18): 3103-10, 2013 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-23401221

RESUMEN

Circulating tumor cells (CTCs), though exceedingly rare in the blood, are nonetheless becoming increasingly important in cancer diagnostics. Despite this keen interest and the growing number of potential clinical applications, there has been limited success in developing a CTC isolation platform that simultaneously optimizes recovery rates, purity, and cell compatibility. Herein, a novel tracheal carina-inspired bifurcated (TRAB) microfilter system is reported, which uses an optimal filter gap size satisfying both 100% theoretical recovery rate and purity, as determined by biomechanical analysis and fluid-structure interaction (FSI) simulations. Biomechanical properties are also used to clearly discriminate between cancer cells and leukocytes, whereby cancer cells are selectively bound to melamine microbeads, which increase the size and stiffness of these cells. Nanoindentation experiments are conducted to measure the stiffness of leukocytes as compared to the microbead-conjugated cancer cells, with these parameters then being used in FSI analyses to optimize the filter gap size. The simulation results show that given a flow rate of 100 µL min(-1), an 8 µm filter gap optimizes the recovery rate and purity. MCF-7 breast cancer cells with solid microbeads are spiked into 3 mL of whole blood and, by using this flow rate along with the optimized microfilter dimensions, the cell mixture passes through the TRAB filter, which achieves a recovery rate of 93% and purity of 59%. Regarding cell compatibility, it is verified that the isolation procedure does not adversely affect cell viability, thus also confirming that the re-collected cancer cells can be cultured for up to 8 days. This work demonstrates a CTC isolation technology platform that optimizes high recovery rates and cell purity while also providing a framework for functional cell studies, potentially enabling even more sensitive and specific cancer diagnostics.


Asunto(s)
Técnicas Analíticas Microfluídicas/métodos , Microscopía de Fuerza Atómica/métodos , Células Neoplásicas Circulantes/metabolismo , Tráquea , Humanos , Microfluídica
19.
Biosens Bioelectron ; 224: 115055, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36630746

RESUMEN

Charcot-Marie-Tooth disease subtype 1A (CMT1A) is one of the most prevalent demyelinating peripheral neuropathies worldwide, caused by duplication of the peripheral myelin protein 22 (PMP22) gene, which is expressed primarily in Schwann cells (SCs). PMP22 overexpression in SCs leads to intracellular aggregation of the protein, which eventually results in demyelination. Unfortunately, previous biochemical approaches have not resulted in an approved treatment for CMT1A disease, compelling the pursuit for a biophysical approach such as electrical stimulation (ES). However, the effects of ES on CMT1A SCs have remained unexplored. In this study, we established PMP22-overexpressed Schwannoma cells as a CMT1A in vitro model, and investigated the biomolecular changes upon applying ES via a custom-made high-throughput ES platform, screening for the condition that delivers optimal therapeutic effects. While PMP22-overexpressed Schwannoma exhibited intracellular PMP22 aggregation, ES at 20 Hz for 1 h improved this phenomenon, bringing PMP22 distribution closer to healthy condition. ES at this condition also enhanced the expression of the genes encoding myelin basic protein (MBP) and myelin-associated glycoprotein (MAG), which are essential for assembling myelin sheath. Furthermore, ES altered the gene expression for myelination-regulating transcription factors Krox-20, Oct-6, c-Jun and Sox10, inducing pro-myelinating effects in PMP22-overexpressed Schwannoma. While electroceuticals has previously been applied in the peripheral nervous system towards acquired peripheral neuropathies such as pain and nerve injury, this study demonstrates its effectiveness towards ameliorating biomolecular abnormalities in an in vitro model of CMT1A, an inherited peripheral neuropathy. These findings will facilitate the clinical translation of an electroceutical treatment for CMT1A.


Asunto(s)
Técnicas Biosensibles , Enfermedad de Charcot-Marie-Tooth , Neurilemoma , Humanos , Proteínas de la Mielina/genética , Proteínas de la Mielina/metabolismo , Vaina de Mielina/genética , Vaina de Mielina/metabolismo , Enfermedad de Charcot-Marie-Tooth/genética , Enfermedad de Charcot-Marie-Tooth/metabolismo , Neurilemoma/metabolismo
20.
ACS Appl Mater Interfaces ; 15(12): 15059-15070, 2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-36809905

RESUMEN

Rare cells, such as circulating tumor cells or circulating fetal cells, provide important information for the diagnosis and prognosis of cancer and prenatal diagnosis. Since undercounting only a few cells can lead to significant misdiagnosis and incorrect decisions in subsequent treatment, it is crucial to minimize cell loss, particularly for rare cells. Moreover, the morphological and genetic information on cells should be preserved as intact as possible for downstream analysis. The conventional immunocytochemistry (ICC), however, fails to meet these requirements, causing unexpected cell loss and deformation of the cell organelles which may mislead the classification of benign and malignant cells. In this study, a novel ICC technique for preparing lossless cellular specimens was developed to improve the diagnostic accuracy of rare cell analysis and analyze intact cellular morphology. To this end, a robust and reproducible porous hydrogel pellicle was developed. This hydrogel encapsulates cells to minimize cell loss from the repeated exchange of reagents and prevent cell deformation. The soft hydrogel pellicle allows stable and intact cell picking for further downstream analysis, which is difficult with conventional ICC methods that permanently immobilize cells. The lossless ICC platform will pave the way for robust and precise rare cell analysis toward clinical practice.


Asunto(s)
Neoplasias , Humanos , Inmunohistoquímica , Porosidad , Hidrogeles
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