BioTechPlex Corporation

Yorba Linda, CA, United States

BioTechPlex Corporation

Yorba Linda, CA, United States
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Wang Y.,BioTechPlex Corporation | Wang Y.,Cytoptics Corporation | Mao H.,BioTechPlex Corporation | Mao H.,Cytoptics Corporation | And 2 more authors.
Nanotechnology | Year: 2010

We have synthesized a chloride sensing quantum dots (QD) nanosensor, Cl-QD, for the dynamic measurements of chloride ion concentration in the millimolar range, a sensitivity that is applicable to most physiological intracellular chloride ion concentration ([Cl-]i) measurements in epithelial cells. The Cl-QD is synthesized by conjugating an anion receptor, 1-(2-mercapto-ethyl)-3-phenyl-thiourea (MEPTU) to a water soluble CdSe/ZnS QD at an emission wavelength of 620 nm. Upon binding of chloride ions to the Cl-QD, a photo-induced electron transfer mechanism caused the fluorescence of the QD to quench. This resulted in an inversely proportional relationship between the chloride ion concentration and the fluorescence intensity of the Cl-QD. We have utilized this Cl-QD to measure [Cl-]i in T84 and CF-PAC cultured cells, with either the C1C-2 or CFTR chloride channels being manipulated by pharmacological chloride channel activators and inhibitors. Activations of C1C-2 and CFTR chloride channels in T84 by the respective lubiprostone and genistein caused predictive increases in the fluorescence of the Cl-QD, i.e., a decrease of [Cl-]i. Conversely, glibenclamide, a chloride channel inhibitor, applied to the CF-PAC cells caused a predictable decrease in the fluorescence of Cl-QD due to the increase of [Cl-]i. These are the first data in using QD-based chloride ion sensors for dynamic measurements of intracellular chloride ion concentrations in epithelial cells. © IOP Publishing Ltd.


Fu R.-H.,China Medical University at Taichung | Wang Y.-C.,Biotechplex Corporation | Liu S.-P.,China Medical University at Taichung | Huang C.-M.,China Medical University at Taichung | And 6 more authors.
Cell Transplantation | Year: 2011

Stem cells are a natural choice for cellular therapy because of their potential to differentiate into a variety of lineages, their capacity for self-renewal in the repair of damaged organs and tissues in vivo, and their ability to generate tissue constructs in vitro. Determining how to efficiently drive stem cell differentiation to a lineage of choice is critical for the success of cellular therapeutics. Many factors are involved in this process, the extracellular microenvironment playing a significant role in controlling cellular behavior. In recent years, researchers have focused on identifying a variety of biomaterials to provide a microenvironment that is conducive to stem cell growth and differentiation and that ultimately mimics the in vivo situation. Appropriate biomaterials support the cellular attachment, proliferation, and lineage-specific differentiation of stem cells. Tissue engineering approaches have been used to incorporate growth factors and morphogenetic factors - factors known to induce lineage commitment of stem cells - into cultures with scaffolding materials, including synthetic and naturally derived biomaterials. This review focuses on various strategies that have been used in stem cell expansion and examines modifications of natural and synthetic materials, as well as various culture conditions, for the maintenance and lineage-specific differentiation of embryonic and adult stem cells. Copyright © 2011 Cognizant Comm. Corp. All rights reserved.


Fu R.-H.,China Medical University at Taichung | Hran H.-J.,China Medical University at Taichung | Chu C.-L.,China Medical University at Taichung | Chu C.-L.,National Health Research Institute | And 7 more authors.
Biotechnology Letters | Year: 2011

Modulation of dendritic cell (DC) fate and function may be one approach for the treatment of inflammatory and autoimmune diseases. n-Butylidenephthalide (BP), derived from Angelica sinensis, at 40 μg/ml significantly decreased the secretion of interleukin-6 and tumor necrosis factor-α by lipopolysaccharide (LPS)-stimulated activation of cultured murine DC2. 4 cells (P < 0. 01). LPS-induced major histocompatibility complex class II (P < 0. 05), CD86 (P < 0. 01) and CD40 (P < 0. 01) expression on DC2. 4 cells was also inhibited by BP. The endocytic capacity of LPS-stimulated DC2. 4 cells was increased by BP (P < 0. 01). The antigen-presenting capacity of LPS-stimulated DC2. 4 cells was decreased by BP (P < 0. 05). Moreover, we confirmed BP attenuates the responses of LPS-stimulated activation of DCs via suppression of NF-κB-dependent pathways. © 2011 Springer Science+Business Media B.V.


Fu R.-H.,China Medical University at Taichung | Liu S.-P.,China Medical University at Taichung | Ou C.-W.,China Medical University at Taichung | Huang C.-M.,China Medical University at Taichung | And 2 more authors.
Acta Biomaterialia | Year: 2010

Cell-based assays have become important tools in the pharmaceutical and biotechnology industries. However, observing and monitoring molecules in cells that mimic the physiological environment is often difficult. Dynamic processes not only increase the accuracy of simulations, but also improve our understanding of the function and regulation of molecules within cells. In this study we used chitosan as a multifunctional biomaterial for selective micropatterning of cells, peptide delivery and covalent bonding with quantum dots (QD) to decrease the cytotoxicity of QD. Our results demonstrate the efficacy of chitosan-QD-peptide-Alexa Fluor 488 in controlling the spread and spatial organization of cells. Cationic chitosan also provided an efficient delivery mechanism to live cells. We used the shift from green to red fluorescence of the chitosan dual color QD peptide to detect biological activity. This methodology has potential applications in high throughput screening of inhibitors and activators of biological mechanisms and pathways and for use in the pharmaceutical industry. © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.


Wang Y.,BioTechPlex Corporation | Wong L.B.,BioTechPlex Corporation | Mao H.,BioTechPlex Corporation
Biomaterials | Year: 2010

We describe a method of using a 3D collagen gel scaffold applied at the air-liquid interface to culture dissociated primary tracheal-bronchial ciliated cells into a ciliated epithelial tissue structure (CETS). This 3D collagen gel culture system enables the induction of ciliogenesis and continuously provides support, maintenance, development, differentiation and propagation for the growth of cilia into the CETS. The CETS developed by this system resembles the ciliary metachronal motility and morphological, histological and physiopharmacological characteristics of cells found in native and in vivo ciliated epithelia. The CETS can be sustained for months with a straightforward and simple maintenance protocol. The integrity of the functional ciliary activity of this CETS enables the evaluation of long-term effects of many pulmonary drug candidates without using animals. © 2009 Elsevier Ltd. All rights reserved.


PubMed | BioTechPlex Corporation
Type: Journal Article | Journal: Tissue engineering. Part C, Methods | Year: 2010

We have devised a simple three-dimensional (3D) tissue-culturing method to induce ciliogenesis from avian embryonic stem (ES) cells by using avian fertilized eggs. Unlike the previous reported techniques, this method does not require trypsinization, which would reduce the viability of the cells; it also does not require an air-liquid interface to induce ciliogenesis and to maintain the growth of the induced ciliated cells. ES cells seeded and attached on this collagen-coated chitosan 3D gel grew spontaneously and robustly. Following 2 weeks in culture with inhibition of embryoid body formation, cells with noticeable and vigorous beating cilia were observed. We measured the ciliary beat frequencies of these ES-differentiated ciliated cells for 40 days. These results were consistent with all reported measurements made for other species of ciliated cells, including human, from our previous study. These data imply that the cilia of these ES-derived ciliated cells, beating at their intrinsic basal autorhythmic rate, preserve the integrity of the regulatory mechanisms of ciliary beat frequency. In conclusion, we have shown that ES cells cultured in a 3D tissue-engineered scaffold is a promising approach for developing an in vitro cell model that closely mimics the in vivo ciliated cell natural milieu. This cell model can potentially be the source of ciliated cells for cell-based high-throughput screening and discovery of pulmonary drugs.


PubMed | BioTechPlex Corporation
Type: Journal Article | Journal: Nanotechnology | Year: 2010

We have synthesized a chloride sensing quantum dots (QD) nanosensor, Cl-QD, for the dynamic measurements of chloride ion concentration in the millimolar range, a sensitivity that is applicable to most physiological intracellular chloride ion concentration ([Cl(-)](i)) measurements in epithelial cells. The Cl-QD is synthesized by conjugating an anion receptor, 1-(2-mercapto-ethyl)-3-phenyl-thiourea (MEPTU) to a water soluble CdSe/ZnS QD at an emission wavelength of 620 nm. Upon binding of chloride ions to the Cl-QD, a photo-induced electron transfer mechanism caused the fluorescence of the QD to quench. This resulted in an inversely proportional relationship between the chloride ion concentration and the fluorescence intensity of the Cl-QD. We have utilized this Cl-QD to measure [Cl(-)](i) in T84 and CF-PAC cultured cells, with either the C1C-2 or CFTR chloride channels being manipulated by pharmacological chloride channel activators and inhibitors. Activations of C1C-2 and CFTR chloride channels in T84 by the respective lubiprostone and genistein caused predictive increases in the fluorescence of the Cl-QD, i.e., a decrease of [Cl(-)](i). Conversely, glibenclamide, a chloride channel inhibitor, applied to the CF-PAC cells caused a predictable decrease in the fluorescence of Cl-QD due to the increase of [Cl(-)](i). These are the first data in using QD-based chloride ion sensors for dynamic measurements of intracellular chloride ion concentrations in epithelial cells.

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