1
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Lebenzon JE, Toxopeus J. Knock down to level up: Reframing RNAi for invertebrate ecophysiology. Comp Biochem Physiol A Mol Integr Physiol 2024; 297:111703. [PMID: 39029617 DOI: 10.1016/j.cbpa.2024.111703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 07/16/2024] [Accepted: 07/16/2024] [Indexed: 07/21/2024]
Abstract
Comparative ecophysiologists strive to understand physiological problems in non-model organisms, but molecular tools such as RNA interference (RNAi) are under-used in our field. Here, we provide a framework for invertebrate ecophysiologists to use RNAi to answer questions focused on physiological processes, rather than as a tool to investigate gene function. We specifically focus on non-model invertebrates, in which the use of other genetic tools (e.g., genetic knockout lines) is less likely. We argue that because RNAi elicits a temporary manipulation of gene expression, and resources to carry out RNAi are technically and financially accessible, it is an effective tool for invertebrate ecophysiologists. We cover the terminology and basic mechanisms of RNA interference as an accessible introduction for "non-molecular" physiologists, include a suggested workflow for identifying RNAi gene targets and validating biologically relevant gene knockdowns, and present a hypothesis-testing framework for using RNAi to answer common questions in the realm of invertebrate ecophysiology. This review encourages invertebrate ecophysiologists to use these tools and workflows to explore physiological processes and bridge genotypes to phenotypes in their animal(s) of interest.
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Affiliation(s)
- Jacqueline E Lebenzon
- Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary, Alberta, Canada T2N 1N4.
| | - Jantina Toxopeus
- Department of Biology, St. Francis Xavier University, 2321 Notre Dame Ave, Antigonish, NS, Canada B2G 2W5
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2
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Dehne M, Neidinger SV, Stark M, Adamo AC, Kraus X, Färber N, Westerhausen C, Bahnemann J. Microfluidic Transfection System and Temperature Strongly Influence the Efficiency of Transient Transfection. ACS OMEGA 2024; 9:21637-21646. [PMID: 38764649 PMCID: PMC11097341 DOI: 10.1021/acsomega.4c02590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 03/30/2024] [Accepted: 04/04/2024] [Indexed: 05/21/2024]
Abstract
For the process of transient transfection (TTF), DNA is often transported into the cells using polyplexes. The polyplex uptake and the subsequent transient expression of the gene of interest are of great importance for a successful transfection. In this study, we investigated a 3D-printed microfluidic system designed to facilitate direct TTF for suspension of CHO-K1 cells. The results demonstrate that this system achieves significantly better results than the manual approach. Furthermore, the effect of both post-transfection incubation time (t) and temperature (T) on polyplex uptake was explored in light of the membrane phase transitions. Attention was paid to obtaining the highest possible transfection efficiency (TFE), viability (V), and viable cell concentration (VCC). Our results show that transfection output measured as product of VCC and TFE is optimal for t = 1 h at T = 22 °C. Moreover, post-transfection incubation at T = 22 °C with short periods of increased T at T = 40 °C were observed to further increase the output. Finally, we found that around T = 19 °C, the TFE increases strongly. This is the membrane phase transition T of CHO-K1 cells, and those results therefore suggest a correlation between membrane order and permeability (and in turn, TFE).
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Affiliation(s)
- Michaela Dehne
- Institute
of Technical Chemistry, Leibniz University
Hannover, Hannover 30167, Germany
- Chair
Technical Biology, Institute of Physics, University of Augsburg, Augsburg 86159, Germany
| | - Simon Valentin Neidinger
- Physiology,
Faculty of Medicine, Institute of Theoretical Medicine, University of Augsburg, Augsburg 86159, Germany
| | - Michael Stark
- Physiology,
Faculty of Medicine, Institute of Theoretical Medicine, University of Augsburg, Augsburg 86159, Germany
| | - Antonia Camilla Adamo
- Physiology,
Faculty of Medicine, Institute of Theoretical Medicine, University of Augsburg, Augsburg 86159, Germany
| | - Xenia Kraus
- Chair
Technical Biology, Institute of Physics, University of Augsburg, Augsburg 86159, Germany
| | - Nicolas Färber
- Physiology,
Faculty of Medicine, Institute of Theoretical Medicine, University of Augsburg, Augsburg 86159, Germany
| | - Christoph Westerhausen
- Physiology,
Faculty of Medicine, Institute of Theoretical Medicine, University of Augsburg, Augsburg 86159, Germany
- Centre
for Advanced Analytics and Predictive Sciences (CAAPS), University of Augsburg, Augsburg 86159, Germany
- Institute
of Physics, University of Augsburg, Augsburg 86159, Germany
| | - Janina Bahnemann
- Chair
Technical Biology, Institute of Physics, University of Augsburg, Augsburg 86159, Germany
- Centre
for Advanced Analytics and Predictive Sciences (CAAPS), University of Augsburg, Augsburg 86159, Germany
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3
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Chen H, Dong X, Ou L, Ma C, Yuan B, Yang K. Thermal-controlled cellular uptake of "hot" nanoparticles. NANOSCALE 2023; 15:12718-12727. [PMID: 37470374 DOI: 10.1039/d3nr02449k] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/21/2023]
Abstract
Nanoparticles (NPs) have shown immense potential in the field of biomedical applications, particularly in NP-based photothermal therapy, which offers a remote-controlled approach to achieve precise temperature control for site-specific heating and sub-cellular tumor treatment. However, the molecular mechanisms underlying related cellular activities, such as the cellular uptake behavior of irradiated NPs in photothermal effects, remain elusive. In this study, we conducted a thorough investigation of the interaction between an irradiated NP with elevated temperature (ranging from 270 to 360 K) and a model bilayer membrane composed of DPPC or DOPC using nonequilibrium coarse-grained molecular dynamics simulations with the implicit-solvent Dry Martini force field. We observe that the interaction between a "hot" NP and a membrane is thermally regulated. In addition, the wrapping of membranes around NPs exhibits a strong dependence on the temperature of the irradiated NP, demonstrating a step-like change in behavior. This membrane wrapping effect is attributed to the heat conduction between NPs and membrane lipids, which occurs almost simultaneously with the membrane deformation and wrapping of NPs during the NP-membrane interaction process. Especially, during the process of heat conduction, a gel-to-fluid phase transition of the membrane may occur, which plays a crucial role in determining the deformation behavior of the membrane. Moreover, it is found that the membrane lipids in the two leaflets exhibit obvious and asymmetric molecular-level responses to heat flux, characterized by significant changes in packing states (e.g., the order parameter of lipid tails and area per lipid) and possible interdigitation between lipids. Furthermore, the thermal-controlled wrapping effect is tightly linked to the properties of NPs (e.g., size, NP-lipid affinity) and lipid species. Our findings are valuable for comprehending the thermal-regulated cellular internalization of NPs and offer insights into devising strategies to precisely modulate NP endocytosis by exploiting the interplay between heating and NP properties.
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Affiliation(s)
- Haibo Chen
- Center for Soft Condensed Matter Physics and Interdisciplinary Research & School of Physical Science and Technology, Soochow University, Suzhou 215006, Jiangsu, China.
| | - Xuewei Dong
- Center for Soft Condensed Matter Physics and Interdisciplinary Research & School of Physical Science and Technology, Soochow University, Suzhou 215006, Jiangsu, China.
| | - Luping Ou
- Center for Soft Condensed Matter Physics and Interdisciplinary Research & School of Physical Science and Technology, Soochow University, Suzhou 215006, Jiangsu, China.
| | - Chiyun Ma
- Center for Soft Condensed Matter Physics and Interdisciplinary Research & School of Physical Science and Technology, Soochow University, Suzhou 215006, Jiangsu, China.
| | - Bing Yuan
- Songshan Lake Materials Laboratory, Dongguan 523808, Guangdong, China
| | - Kai Yang
- Center for Soft Condensed Matter Physics and Interdisciplinary Research & School of Physical Science and Technology, Soochow University, Suzhou 215006, Jiangsu, China.
- Songshan Lake Materials Laboratory, Dongguan 523808, Guangdong, China
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4
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Reddel CJ, Pennings GJ, Chen VM, Gnanenthiran S, Kritharides L. Colchicine as a Modulator of Platelet Function: A Systematic Review. Semin Thromb Hemost 2022; 48:552-567. [PMID: 35882248 DOI: 10.1055/s-0042-1749660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
The microtubule inhibitor and anti-inflammatory agent colchicine is used to treat a range of conditions involving inflammasome activation in monocytes and neutrophils, and is now known to prevent coronary and cerebrovascular events. In vitro studies dating back more than 50 years showed a direct effect of colchicine on platelets, but as little contemporary attention has been paid to this area, we have critically reviewed the effects of colchicine on diverse aspects of platelet biology in vitro and in vivo. In this systematic review we searched Embase, Medline, and PubMed for articles testing platelets after incubation with colchicine and/or reporting a clinical effect of colchicine treatment on platelet function, including only papers available in English and excluding reviews and conference abstracts. We identified 98 relevant articles and grouped their findings based on the type of study and platelet function test. In vitro, colchicine inhibits traditional platelet functions, including aggregation, clotting, degranulation, and platelet-derived extracellular vesicle formation, although many of these effects were reported at apparently supraphysiological concentrations. Physiological concentrations of colchicine inhibit collagen- and calcium ionophore-induced platelet aggregation and internal signaling. There have been limited studies of in vivo effects on platelets. The colchicine-platelet interaction has the potential to contribute to colchicine-mediated reduction in cardiovascular events, but there is a pressing need for high quality clinical research in this area.
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Affiliation(s)
- Caroline J Reddel
- ANZAC Research Institute, University of Sydney, Concord Repatriation General Hospital, Sydney, Australia
| | - Gabrielle J Pennings
- ANZAC Research Institute, University of Sydney, Concord Repatriation General Hospital, Sydney, Australia
| | - Vivien M Chen
- ANZAC Research Institute, University of Sydney, Concord Repatriation General Hospital, Sydney, Australia.,Department of Haematology, Concord Repatriation General Hospital, Sydney, Australia
| | - Sonali Gnanenthiran
- ANZAC Research Institute, University of Sydney, Concord Repatriation General Hospital, Sydney, Australia.,Department of Cardiology, Concord Repatriation General Hospital, Sydney, Australia
| | - Leonard Kritharides
- ANZAC Research Institute, University of Sydney, Concord Repatriation General Hospital, Sydney, Australia.,Department of Cardiology, Concord Repatriation General Hospital, Sydney, Australia
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5
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Wei Y, Chen H, Li YX, He K, Yang K, Pang HB. Synergistic Entry of Individual Nanoparticles into Mammalian Cells Driven by Free Energy Decline and Regulated by Their Sizes. ACS NANO 2022; 16:5885-5897. [PMID: 35302738 DOI: 10.1021/acsnano.1c11068] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Cell entry is one of the common prerequisites for nanomaterial applications. Despite extensive studies on a homogeneous group of nanoparticles (NPs), fewer studies have been performed when two or more types of NPs were coadministrated. We previously described a synergistic cell entry process for two heterogeneous groups of NPs, where NPs functionalized with TAT (transactivator of transcription) peptide (T-NPs) stimulate the cellular uptake of coadministered unfunctionalized NPs (bystander NPs, B-NPs). Here, we show that the synergistic cell entry of NPs is driven by free energy decline and depends on B-NP sizes. Simulations showed that when separately placed initially, two NPs first move toward each other instead of initiating cell entry individually. Only T-NP invokes an inward bending of membrane mimicking endocytosis, which attracts the nearby NPs into the same "vesicle". A two-phase free energy decline of the entire system occurred as two NPs get closer until contact, which is likely the thermodynamic driver for synergistic NP coentry. Experimentally, we found that T-NPs increase the apparent affinity of B-NPs to plasma membrane, suggesting that T-NPs help B-NPs "trapped" in the endocytic vesicles. Next, we varied the sizes of B-NPs and found that bystander activity peaks around 50 nm. Simulations also showed that the size of B-NPs influences the free energy decline, and thus the tendency and dynamics of NP coentry. These efforts provide a system to further understand the synergistic cell entry among individual NPs or multiple NP types on a biophysical basis and shed light on the future design of nanostructures for intracellular delivery.
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Affiliation(s)
- Yushuang Wei
- Department of Pharmaceutics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Haibo Chen
- Center for Soft Condensed Matter Physics and Interdisciplinary Research & School of Physical Science and Technology, Soochow University, Suzhou 215006, China
| | - Yue-Xuan Li
- Department of Pharmaceutics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Kejie He
- Center for Soft Condensed Matter Physics and Interdisciplinary Research & School of Physical Science and Technology, Soochow University, Suzhou 215006, China
| | - Kai Yang
- Center for Soft Condensed Matter Physics and Interdisciplinary Research & School of Physical Science and Technology, Soochow University, Suzhou 215006, China
| | - Hong-Bo Pang
- Department of Pharmaceutics, University of Minnesota, Minneapolis, Minnesota 55455, United States
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6
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Abe M, Makino A, Murate M, Hullin-Matsuda F, Yanagawa M, Sako Y, Kobayashi T. PMP2/FABP8 induces PI(4,5)P 2-dependent transbilayer reorganization of sphingomyelin in the plasma membrane. Cell Rep 2021; 37:109935. [PMID: 34758297 DOI: 10.1016/j.celrep.2021.109935] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 08/20/2021] [Accepted: 10/13/2021] [Indexed: 12/11/2022] Open
Abstract
Sphingomyelin (SM) is a mammalian lipid mainly distributed in the outer leaflet of the plasma membrane (PM). We show that peripheral myelin protein 2 (PMP2), a member of the fatty-acid-binding protein (FABP) family, can localize at the PM and controls the transbilayer distribution of SM. Genetic screening with genome-wide small hairpin RNA libraries identifies PMP2 as a protein involved in the transbilayer movement of SM. A biochemical assay demonstrates that PMP2 is a phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2)-binding protein. PMP2 induces the tubulation of model membranes in a PI(4,5)P2-dependent manner, accompanied by the modification of the transbilayer membrane distribution of lipids. In the PM of PMP2-overexpressing cells, inner-leaflet SM is increased whereas outer-leaflet SM is reduced. PMP2 is a causative protein of Charcot-Marie-Tooth disease (CMT). A mutation in PMP2 associated with CMT increases its affinity for PI(4,5)P2, inducing membrane tubulation and the subsequent transbilayer movement of lipids.
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Affiliation(s)
- Mitsuhiro Abe
- Lipid Biology Laboratory, RIKEN, Wako, Saitama 351-0198, Japan; Cellular Informatics Laboratory, RIKEN, Wako, Saitama 351-0198, Japan.
| | - Asami Makino
- Lipid Biology Laboratory, RIKEN, Wako, Saitama 351-0198, Japan; Cellular Informatics Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
| | - Motohide Murate
- Lipid Biology Laboratory, RIKEN, Wako, Saitama 351-0198, Japan; Cellular Informatics Laboratory, RIKEN, Wako, Saitama 351-0198, Japan; Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401 Illkirch, France
| | - Françoise Hullin-Matsuda
- Lipid Biology Laboratory, RIKEN, Wako, Saitama 351-0198, Japan; Université de Lyon, CarMeN Laboratory, INSERM U1060, INRAE U1397, Université Claude Bernard Lyon 1, 69495 Pierre-Benite, France
| | - Masataka Yanagawa
- Cellular Informatics Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
| | - Yasushi Sako
- Cellular Informatics Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
| | - Toshihide Kobayashi
- Lipid Biology Laboratory, RIKEN, Wako, Saitama 351-0198, Japan; Cellular Informatics Laboratory, RIKEN, Wako, Saitama 351-0198, Japan; Laboratoire de Bioimagerie et Pathologies, UMR 7021 CNRS, Faculté de Pharmacie, Université de Strasbourg, 67401 Illkirch, France.
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7
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Abstract
Nanotechnology has been widely applied to medical interventions for prevention, diagnostics, and therapeutics of diseases, and the application of nanotechnology for medical purposes, which is called as a term "nanomedicine" has received tremendous attention. In particular, the design and development of nanoparticle for biosensors have received a great deal of attention, since those are most impactful area of clinical translation showing potential breakthrough in early diagnosis of diseases such as cancers and infections. For example, the nanoparticles that have intrinsic unique features such as magnetic responsive characteristics or photoluminescence can be utilized for noninvasive visualization of inner body. Drug delivery that makes use of drug-containing nanoparticles as a carrier is another field of study, in which the particulate form nanomedicine is given by parenteral administration for further systemic targeting to pathological tissues. In addition, encapsulation into nanoparticles gives the opportunity to secure the sensitive therapeutic payloads that are readily degraded or deactivated until reached to the target in biological environments, or to provide sufficient solubilization (e.g., to deliver compounds which have physicochemical properties that strongly limit their aqueous solubility and therefore systemic bioavailability). The nanomedicine is further intended to enhance the targeting index such as increased specificity and reduced false binding, thus improve the diagnostic and therapeutic performances. In this chapter, principles of nanomaterials for medicine will be thoroughly covered with applications for imaging-based diagnostics and therapeutics.
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Affiliation(s)
- Jinmyoung Joo
- Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, South Korea.
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8
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Chatterjee A, Nagarajan H, Padmanabhan P, Vetrivel U, Therese KL, Janakiraman N. Understanding the Uptake Mechanism and Interaction Potential of the Designed Peptide and Preparation of Composite Fiber Matrix for Fungal Keratitis. ACS OMEGA 2020; 5:12090-12102. [PMID: 32548388 PMCID: PMC7271034 DOI: 10.1021/acsomega.0c00321] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 05/07/2020] [Indexed: 05/05/2023]
Abstract
The conventional use of antibiotics for the treatment of infectious keratitis currently faces two major challenges: poor drug penetration and the emergence of antibiotic resistance in microbial strains. Cell-penetrating peptides (CPPs) with antimicrobial properties have the potential to address these challenges. However, their mode of action, mechanism of uptake, and interaction potential have not been explored in detail. In this study, we probed the mechanism of uptake and interaction potential of our previously designed peptides (VRF005 and VRF007). Our results showed that VRF005 undergoes direct translocation and induces a rough membrane surface, whereas VRF007 undergoes clathrin-mediated endocytic uptake. The gel shift assay showed that VRF005 is bound to genomic DNA, whereas VRF007 is bound to chitin and β-d-glucan. Gene expression studies revealed the effect of peptide VRF005 on Candida albicans transcription. Molecular docking and simulations showed that VRF005 forms noncovalent interactions (such as H-bonding and water bridges) with natamycin. It exhibited synergistic antifungal activity in the colony-forming assay. VRF005, functionalized in the polycaprolactone fiber matrix, showed sustained delivery and antifungal activity.
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Affiliation(s)
- Amit Chatterjee
- Department
of Nanobiotechnology, Vision Research Foundation, Sankara Nethralaya, Chennai 600006, Tamil Nadu, India
- School
of Chemical and Biotechnology, SASTRA University, Tanjore 613401, Tamil Nadu, India
| | - Hemavathy Nagarajan
- Centre
for Bioinformatics, Vision Research Foundation, Sankara Nethralaya, Chennai 600006, Tamil Nadu, India
| | - Prema Padmanabhan
- Department
of Cornea, Medical Research Foundation, Sankara Nethralaya, Chennai 600006, Tamil Nadu, India
| | - Umashankar Vetrivel
- Centre
for Bioinformatics, Vision Research Foundation, Sankara Nethralaya, Chennai 600006, Tamil Nadu, India
| | - Kulandhai Lily Therese
- L&T
Microbiology Research Centre, Vision Research Foundation, Sankara Nethralaya, Chennai 600006, Tamil Nadu, India
| | - Narayanan Janakiraman
- Department
of Nanobiotechnology, Vision Research Foundation, Sankara Nethralaya, Chennai 600006, Tamil Nadu, India
- .
Tel: +91-44-28271616 (ext. 1358). Fax: +91-44-28254180
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9
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Zhang Y, Wang H, Stewart S, Jiang B, Ou W, Zhao G, He X. Cold-Responsive Nanoparticle Enables Intracellular Delivery and Rapid Release of Trehalose for Organic-Solvent-Free Cryopreservation. NANO LETTERS 2019; 19:9051-9061. [PMID: 31680526 DOI: 10.1021/acs.nanolett.9b04109] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Conventional cryopreservation of mammalian cells requires the use of toxic organic solvents (e.g., dimethyl sulfoxide) as cryoprotectants. Consequently, the cryopreserved cells must undergo a tedious washing procedure to remove the organic solvents for their further applications in cell-based medicine, and many of the precious cells may be lost or killed during the procedure. Trehalose has been explored as a nontoxic alternative to traditional cryoprotectants. However, mammalian cells do not synthesize trehalose or express trehalose transporters in their membranes, and the lack of an approach for the efficient intracellular delivery of trehalose has been a major hurdle for its use in cell cryopreservation. In this study, a cold-responsive polymer (poly(N-isopropylacrylamide-co-butyl acrylate)) is utilized to synthesize nanoparticles for the encapsulation and intracellular delivery of trehalose. The trehalose-laden nanoparticles can be efficiently taken up by mammalian cells. The nanoparticles quickly and irreversibly disassemble upon cold treatment, enabling the controlled and rapid release of trehalose from the nanoparticles inside cells. The latter is confirmed by an evident increase in cell volume upon cold treatment. This rapid cold-triggered intracellular release of trehalose is crucial to developing a fast protocol to cryopreserve cells using trehalose. Cells with intracellular trehalose delivered using the nanoparticles show comparable postcryopreservation viability compared to that of cells treated with DMSO, eliminating the need for the tedious and cell-damaging washing procedure required for using the DMSO-cryopreserved cells in vivo. This cold-responsive nanoparticle may greatly facilitate the use of trehalose as a nontoxic cryoprotectant for banking cells and tissues to meet their high demand by modern cell-based medicine.
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Affiliation(s)
- Yuntian Zhang
- Department of Electronic Science and Technology , University of Science and Technology of China , Hefei , Anhui 230027 , China
| | - Hai Wang
- CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience , National Center for Nanoscience and Technology , Beijing 100190 , China
- University of Chinese Academy of Sciences , Beijing 100049 , China
| | | | | | | | - Gang Zhao
- Department of Electronic Science and Technology , University of Science and Technology of China , Hefei , Anhui 230027 , China
| | - Xiaoming He
- Marlene and Stewart Greenebaum Comprehensive Cancer Center , University of Maryland , Baltimore , Maryland 21201 , United States
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10
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Interleukin 10 promotes macrophage uptake of HDL and LDL by stimulating fluid-phase endocytosis. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1865:158537. [PMID: 31676439 DOI: 10.1016/j.bbalip.2019.158537] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 09/06/2019] [Accepted: 09/19/2019] [Indexed: 01/01/2023]
Abstract
OBJECTIVE Highly elevated plasma levels of interleukin-10 (IL-10) are causally associated with "Disappearing HDL Syndrome" and low plasma LDL-cholesterol, but the underlying mechanism is poorly understood. Fluid-phase endocytosis, a process highly dependent on actin dynamics, enables cells to internalize relatively high amounts of extracellular fluids and solutes. We sought to investigate whether IL-10 induces lipoprotein uptake by fluid-phase endocytosis in macrophages. METHODS AND RESULTS Macrophages (RAW264.7, Kupffer and human) were incubated with vehicle (PBS) or IL-10 (20 ng/ml) for 7 days. Uptake of HDL, LDL, and/or fluid-phase endocytosis probes (albumin-Alexa680®, 70 kDa FITC-Dextran and Lucifer Yellow, LY) was evaluated by FACS. Intracellular cofilin and phosphorylated cofilin (p-cofilin) levels were determined by immunoblotting. Macrophage uptake of lipoproteins and probes was non-saturable and increased after IL-10 incubation (p < 0.0001). Furthermore, pre-incubation with fluid-phase endocytosis inhibitors (LY294002, Latrunculin A, and Amiloride) significantly reduced uptake (p < 0.05). IL-10 increased the cofilin/p-cofilin ratio (p = 0.021), signifying increased cofilin activation and hence filamentous actin. Consistently, phalloidin staining revealed increased filamentous actin in macrophages after IL-10 treatment (p = 0.0018). Finally, RNA-seq analysis demonstrated enrichment of gene sets related to actin filament dynamics, membrane ruffle formation and endocytosis in IL-10-treated macrophages (p < 0.05). IL-10 did not alter mRNA levels of Ldlr, Vldlr, Scarb1, Cd36 or Lrp1. In primary human monocyte-derived macrophages and murine Kupffer cells, IL-10 incubation also increased uptake of lipoproteins, albumin and LY (p < 0.01). CONCLUSIONS Interleukin-10 induces the uptake of HDL and LDL by fluid-phase endocytosis by increasing actin-filament rearrangement in macrophages, thus providing a plausible mechanism contributing to "Disappearing HDL Syndrome".
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11
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Bynum JA, Meledeo MA, Peltier GC, McIntosh CS, Taylor AS, Montgomery RK, Reddoch-Cardenas KM, Getz TM, Fitzpatrick MG, Cap AP. Evaluation of a lyophilized platelet-derived hemostatic product. Transfusion 2019; 59:1490-1498. [PMID: 30980737 DOI: 10.1111/trf.15167] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 10/31/2018] [Accepted: 11/01/2018] [Indexed: 01/10/2023]
Abstract
BACKGROUND Current limitations of platelet shelf life to 5 days have led to an increasingly greater demand for hemostatic agents with greater longevity. The objective of this study was to evaluate the function of a lyophilized platelet-derived hemostatic product (thrombosome [TS]) as a potential alternative to fresh platelets. METHODS Platelets were collected from whole blood from healthy donors. TSs were reconstituted with water and added to various configurations of reassembled whole blood (platelets, plasma, and RBCs); measures included rotational thromboelastometry (ROTEM), optical aggregometry, mitochondrial function, calibrated automated thrombogram, collagen adhesion under flow (shear flow assay), and flow cytometry. RESULTS In ROTEM, no differences were observed between maximum clot formation values for contact pathway activation thromboelastometry tests with TSs or platelet samples. Significantly decreased aggregation was observed in the TSs versus platelets (p < 0.001 for all agonists). Flow cytometry measures demonstrated significant decreases in glycoprotein Ib expression and increases in phosphatidylserine expression in the TS group (p < 0.01). The calibrated automated thrombogram assay was suggestive (lag time and peak thrombin) that the TSs might have some thrombogenic properties. Measurements of mitochondrial function revealed that TSs had no functional mitochondria. CONCLUSION In this study, TSs were shown to have nonfunctional mitochondria. ROTEM measures revealed that the TSs had no impact on clot strength. Likewise, compared to platelets, the TSs displayed minimal aggregation, had significantly more phosphatidylserine (measure of activation status), but had the ability to adhere to a collagen surface under flow conditions and contribute to clot formation and induced greater thrombin generation.
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Affiliation(s)
- James A Bynum
- Coagulation and Blood Research Program, U.S. Army Institute of Surgical Research, Fort Sam Houston, Texas
| | - Michael A Meledeo
- Coagulation and Blood Research Program, U.S. Army Institute of Surgical Research, Fort Sam Houston, Texas
| | - Grantham C Peltier
- Coagulation and Blood Research Program, U.S. Army Institute of Surgical Research, Fort Sam Houston, Texas
| | - Colby S McIntosh
- Coagulation and Blood Research Program, U.S. Army Institute of Surgical Research, Fort Sam Houston, Texas
| | - Ashley S Taylor
- Coagulation and Blood Research Program, U.S. Army Institute of Surgical Research, Fort Sam Houston, Texas
| | - Robbie K Montgomery
- Coagulation and Blood Research Program, U.S. Army Institute of Surgical Research, Fort Sam Houston, Texas
| | - Kristin M Reddoch-Cardenas
- Coagulation and Blood Research Program, U.S. Army Institute of Surgical Research, Fort Sam Houston, Texas
| | | | | | - Andrew P Cap
- Coagulation and Blood Research Program, U.S. Army Institute of Surgical Research, Fort Sam Houston, Texas
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12
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Jaksch S, Koutsioubas A, Mattauch S, Holderer O, Frielinghaus H. Long-range excitations in phospholipid membranes. Chem Phys Lipids 2019; 225:104788. [PMID: 31310735 DOI: 10.1016/j.chemphyslip.2019.104788] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 06/19/2019] [Accepted: 06/24/2019] [Indexed: 10/26/2022]
Abstract
We investigated the existence of long-range excitations and correlated structures in phospholipid membranes by means of grazing-incidence neutron spin echo spectroscopy, grazing-incidence small-angle neutron scattering, and corresponding theoretical calculations inspired by smectic-membrane theory. All these methods confirmed the existence of thermal excitations in the plane of the surface of the phospholipid membranes or the corresponding structures, respectively. Also, these measurements revealed a temperature dependence of these excitations. These excitations are associated with 100 nm in-plane correlations around physiological temperatures and of 75 nm at 16 °C. A single excitation has an energy around the μeV-regime. A temperature series revealed a high abundance at physiological temperatures and pronounced long-range in-plane structures, which are strongly suppressed at temperatures below 20 °C. From the length-scales and energy transfers involved we surmise that these excitations may play a role in several functions of the cell membranes such as stability and energy dissipation along the membrane. From a fundamental point of view, the observed behavior of those excitations is congruent with that of a quasi-particle (surface mode phonon, smomon) that exists in the plane of phospholipid membranes.
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Affiliation(s)
- Sebastian Jaksch
- Forschungszentrum Jülich GmbH, JCNS at Heinz Maier-Leibnitz Zentrum, Lichtenberstraße 1, 85747 Garching, Germany.
| | - Alexandros Koutsioubas
- Forschungszentrum Jülich GmbH, JCNS at Heinz Maier-Leibnitz Zentrum, Lichtenberstraße 1, 85747 Garching, Germany
| | - Stefan Mattauch
- Forschungszentrum Jülich GmbH, JCNS at Heinz Maier-Leibnitz Zentrum, Lichtenberstraße 1, 85747 Garching, Germany
| | - Olaf Holderer
- Forschungszentrum Jülich GmbH, JCNS at Heinz Maier-Leibnitz Zentrum, Lichtenberstraße 1, 85747 Garching, Germany
| | - Henrich Frielinghaus
- Forschungszentrum Jülich GmbH, JCNS at Heinz Maier-Leibnitz Zentrum, Lichtenberstraße 1, 85747 Garching, Germany
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13
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Wang B, Liu G, Balamurugan V, Sui Y, Wang G, Song Y, Chang Q. Apatite nanoparticles mediate intracellular delivery of trehalose and increase survival of cryopreserved cells. Cryobiology 2019; 86:103-110. [DOI: 10.1016/j.cryobiol.2018.11.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 11/12/2018] [Accepted: 11/13/2018] [Indexed: 12/18/2022]
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14
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Wan H, Ma H, Zhu S, Wang F, Tian Y, Ma R, Yang Q, Hu Z, Zhu T, Wang W, Ma Z, Zhang M, Zhong Y, Sun H, Liang Y, Dai H. Developing a Bright NIR-II Fluorophore with Fast Renal Excretion and Its Application in Molecular Imaging of Immune Checkpoint PD-L1. ADVANCED FUNCTIONAL MATERIALS 2018; 28:1804956. [PMID: 31832053 PMCID: PMC6907024 DOI: 10.1002/adfm.201804956] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Indexed: 05/22/2023]
Abstract
Fluorescence imaging in the second near-infrared (NIR-II) window holds impressive advantages of enhanced penetration depth and improved signal-to-noise ratio. Bright NIR-II fluorophores with renal excretion ability and low tissue accumulation are favorable for in vivo molecular imaging applications as they can render the target-mediated molecular imaging process easily distinguishable. Here, a probe (anti-PD-L1-BGP6) comprising a fluorophore (IR-BGP6) covalently bonded to the programmed cell death ligand-1 monoclonal antibody (PD-L1 mAb) for molecular imaging of immune checkpoint PD-L1 (a targeting site upregulated in various tumors for cancer imaging) in the NIR-II window is reported. Through molecular optimization, the bright NIR-II fluorophore IR-BGP6 with fast renal excretion (≈91% excretion in general through urine within the first 10 h postinjection) is developed. The conjugate anti-PD-L1-BGP6 succeeds in profiling PD-L1 expression and realizes efficient noninvasive molecular imaging in vivo, achieving a tumor to normal tissue (T/NT) signal ratio as high as ≈9.5. Compared with the NIR-II fluorophore with high nonspecific tissue accumulation, IR-BGP6 derived PD-L1 imaging significantly enhances the molecular imaging performance, serving as a strong tool for potentially studying underlying mechanism of immunotherapy. The work provides rationales to design renal-excreted NIR-II fluorophores and illustrate their advantages for in vivo molecular imaging.
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Affiliation(s)
- Hao Wan
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Huilong Ma
- Department of Materials Science and Engineering, South University of Science and Technology of China, Shenzhen 518055, China
| | - Shoujun Zhu
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - FeiFei Wang
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Ye Tian
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Rui Ma
- Department of Materials Science and Engineering, South University of Science and Technology of China, Shenzhen 518055, China
| | - Qinglai Yang
- Department of Materials Science and Engineering, South University of Science and Technology of China, Shenzhen 518055, China
| | - Zhubin Hu
- State Key Laboratory of Precision Spectroscopy, School of Physics and Materials Science, East China Normal University Shanghai 200062, China
| | - Tong Zhu
- School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Weizhi Wang
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Zhuoran Ma
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Mingxi Zhang
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Yeteng Zhong
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
| | - Haitao Sun
- State Key Laboratory of Precision Spectroscopy, School of Physics and Materials Science, East China Normal University Shanghai 200062, China
| | - Yongye Liang
- Department of Materials Science and Engineering, South University of Science and Technology of China, Shenzhen 518055, China
| | - Hongjie Dai
- Department of Chemistry, Stanford University, Stanford, CA 94305, USA
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15
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Chanaday NL, Kavalali ET. Time course and temperature dependence of synaptic vesicle endocytosis. FEBS Lett 2018; 592:3606-3614. [DOI: 10.1002/1873-3468.13268] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 10/02/2018] [Accepted: 10/06/2018] [Indexed: 11/07/2022]
Affiliation(s)
- Natali L. Chanaday
- Department of Pharmacology; Vanderbilt Brain Institute; Vanderbilt University; Nashville TN USA
| | - Ege T. Kavalali
- Department of Pharmacology; Vanderbilt Brain Institute; Vanderbilt University; Nashville TN USA
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Morrison KR, Ngo V, Cardullo RA, Reznick DN. How fish eggs are preadapted for the evolution of matrotrophy. Proc Biol Sci 2018; 284:rspb.2017.1342. [PMID: 29167357 DOI: 10.1098/rspb.2017.1342] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 10/19/2017] [Indexed: 11/12/2022] Open
Abstract
Teleost fishes evolved livebearing via egg retention 14 times. Matrotrophy has evolved within 12 of those lineages. By contrast, squamate reptiles evolved livebearing over 115 times, but only two to four of those lineages are known to have evolved matrotrophy. Is the discrepancy between these organisms in the probability of this transition caused by differences in their eggs? We show that the eggs of oviparous species in the superorder Atherinomorpha can acquire small organic molecules from their surrounding environment against a concentration gradient via mechanisms of active transport. Uptake rates were inhibited by competing radiolabelled amino acids against unlabelled versions of themselves. Transport was non-specific as uptake rates were similar for l-leucine and its biologically uncommon enantiomer d-leucine. Eggs are also capable of transporting larger microspheres across the membrane, but transport is inhibited at temperatures below 4°C, suggesting active transport occurs via pinocytosis. Conflict theory predicts that the ability of the egg to acquire maternal resources will facilitate the embryo-parent arms race that leads to the evolution of matrotrophy following the transition to livebearing. The shelled eggs of amniotes lack such access to maternal resources when retained in the evolution of viviparity.
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Affiliation(s)
- Keenan R Morrison
- Department of Biology, University of California, Riverside, CA 92507, USA
| | - Vyvian Ngo
- Department of Biology, University of California, Riverside, CA 92507, USA
| | - Richard A Cardullo
- Department of Biology, University of California, Riverside, CA 92507, USA
| | - David N Reznick
- Department of Biology, University of California, Riverside, CA 92507, USA
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17
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Grozdova ID, Badun GA, Chernysheva MG, Orlov VN, Romanyuk AV, Melik-Nubarov NS. Increase in the length of poly(ethylene oxide) blocks in amphiphilic copolymers facilitates their cellular uptake. J Appl Polym Sci 2017. [DOI: 10.1002/app.45492] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Irene D. Grozdova
- School of Chemistry; Lomonosov Moscow State University; GSP-1, Leninskie Gory 1, Building 3 Moscow 119991 Russia
| | - Gennadiy A. Badun
- School of Chemistry; Lomonosov Moscow State University; GSP-1, Leninskie Gory 1, Building 3 Moscow 119991 Russia
| | - Maria G. Chernysheva
- School of Chemistry; Lomonosov Moscow State University; GSP-1, Leninskie Gory 1, Building 3 Moscow 119991 Russia
| | - Victor N. Orlov
- A. N. Belozersky Institute of Physico-Chemical Biology; Lomonosov Moscow State University; GSP-1, Leninskie Gory 1, Building 40, Moscow 119991 Russia
| | - Andrey V. Romanyuk
- School of Chemistry; Lomonosov Moscow State University; GSP-1, Leninskie Gory 1, Building 3 Moscow 119991 Russia
| | - Nikolay S. Melik-Nubarov
- School of Chemistry; Lomonosov Moscow State University; GSP-1, Leninskie Gory 1, Building 3 Moscow 119991 Russia
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18
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Exploiting macrophage autophagy-lysosomal biogenesis as a therapy for atherosclerosis. Nat Commun 2017; 8:15750. [PMID: 28589926 PMCID: PMC5467270 DOI: 10.1038/ncomms15750] [Citation(s) in RCA: 233] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 04/25/2017] [Indexed: 12/15/2022] Open
Abstract
Macrophages specialize in removing lipids and debris present in the atherosclerotic plaque. However, plaque progression renders macrophages unable to degrade exogenous atherogenic material and endogenous cargo including dysfunctional proteins and organelles. Here we show that a decline in the autophagy–lysosome system contributes to this as evidenced by a derangement in key autophagy markers in both mouse and human atherosclerotic plaques. By augmenting macrophage TFEB, the master transcriptional regulator of autophagy–lysosomal biogenesis, we can reverse the autophagy dysfunction of plaques, enhance aggrephagy of p62-enriched protein aggregates and blunt macrophage apoptosis and pro-inflammatory IL-1β levels, leading to reduced atherosclerosis. In order to harness this degradative response therapeutically, we also describe a natural sugar called trehalose as an inducer of macrophage autophagy–lysosomal biogenesis and show trehalose's ability to recapitulate the atheroprotective properties of macrophage TFEB overexpression. Our data support this practical method of enhancing the degradative capacity of macrophages as a therapy for atherosclerotic vascular disease. Dysfunction of autophagy in plaque macrophages aggravates atherosclerosis. Here the authors show that induction of macrophage autophagy–lysosomal biogenesis either genetically by overexpression of the master transcriptional regulator of this process, TFEB, or pharmacologically with trehalose is atheroprotective.
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19
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Zhang M, Oldenhof H, Sieme H, Wolkers WF. Combining endocytic and freezing-induced trehalose uptake for cryopreservation of mammalian cells. Biotechnol Prog 2016; 33:229-235. [DOI: 10.1002/btpr.2399] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2016] [Revised: 09/06/2016] [Indexed: 01/25/2023]
Affiliation(s)
- Miao Zhang
- Inst. of Multiphase Processes; Leibniz Universität Hannover; Hannover Germany
| | - Harriëtte Oldenhof
- Clinic for Horses, Unit for Reproductive Medicine; University of Veterinary Medicine Hannover; Hannover Germany
| | - Harald Sieme
- Clinic for Horses, Unit for Reproductive Medicine; University of Veterinary Medicine Hannover; Hannover Germany
| | - Willem F. Wolkers
- Inst. of Multiphase Processes; Leibniz Universität Hannover; Hannover Germany
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20
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Qiao J, Dong P, Mu X, Qi L, Xiao R. Folic acid-conjugated fluorescent polymer for up-regulation folate receptor expression study via targeted imaging of tumor cells. Biosens Bioelectron 2016; 78:147-153. [DOI: 10.1016/j.bios.2015.11.021] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 10/20/2015] [Accepted: 11/08/2015] [Indexed: 01/18/2023]
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21
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Kim J, Kim J, Jeong C, Kim WJ. Synergistic nanomedicine by combined gene and photothermal therapy. Adv Drug Deliv Rev 2016; 98:99-112. [PMID: 26748259 DOI: 10.1016/j.addr.2015.12.018] [Citation(s) in RCA: 170] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2015] [Revised: 12/20/2015] [Accepted: 12/22/2015] [Indexed: 12/19/2022]
Abstract
To date, various nanomaterials with the ability for gene delivery or photothermal effect have been developed in the field of biomedicine. The therapeutic potential of these nanomaterials has raised considerable interests in their use in potential next-generation strategies for effective anticancer therapy. In particular, the advancement of novel nanomedicines utilizing both therapeutic strategies of gene delivery and photothermal effect has generated much optimism regarding the imminent development of effective and successful cancer treatments. In this review, we discuss current research progress with regard to combined gene and photothermal therapy. This review focuses on synergistic therapeutic systems combining gene regulation and photothermal ablation as well as logically designed nano-carriers aimed at enhancing the delivery efficiency of therapeutic genes using the photothermal effect. The examples detailed in this review provide insight to further our understanding of combinatorial gene and photothermal therapy, thus paving the way for the design of promising nanomedicines.
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22
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Abazari A, Chakraborty N, Hand S, Aksan A, Toner M. A Raman microspectroscopy study of water and trehalose in spin-dried cells. Biophys J 2015; 107:2253-62. [PMID: 25418294 DOI: 10.1016/j.bpj.2014.09.032] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 09/24/2014] [Accepted: 09/25/2014] [Indexed: 10/24/2022] Open
Abstract
Long-term storage of desiccated nucleated mammalian cells at ambient temperature may be accomplished in a stable glassy state, which can be achieved by removal of water from the biological sample in the presence of glass-forming agents including trehalose. The stability of the glass may be compromised due to a nonuniform distribution of residual water and trehalose within and around the desiccated cells. Thus, quantification of water and trehalose contents at the single-cell level is critical for predicting the glass formation and stability for dry storage. Using Raman microspectroscopy, we estimated the trehalose and residual water contents in the microenvironment of spin-dried cells. Individual cells with or without intracellular trehalose were embedded in a solid thin layer of extracellular trehalose after spin-drying. We found strong evidence suggesting that the residual water was bound at a 2:1 water/trehalose molar ratio in both the extracellular and intracellular milieus. Other than the water associated with trehalose, we did not find any more residual water in the spin-dried sample, intra- or extracellularly. The extracellular trehalose film exhibited characteristics of an amorphous state with a glass transition temperature of ?22°C. The intracellular milieu also dried to levels suitable for glass formation at room temperature. These findings demonstrate a method for quantification of water and trehalose in desiccated specimens using confocal Raman microspectroscopy. This approach has broad use in desiccation studies to carefully investigate the relationship of water and trehalose content and distribution with the tolerance to drying in mammalian cells.
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Affiliation(s)
- Alireza Abazari
- The Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, Massachusetts
| | - Nilay Chakraborty
- Department of Mechanical Engineering, University of Michigan-Dearborn, Dearborn, Michigan
| | - Steven Hand
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana
| | - Alptekin Aksan
- Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota
| | - Mehmet Toner
- The Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, Massachusetts.
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23
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Abazari A, Meimetis LG, Budin G, Bale SS, Weissleder R, Toner M. Engineered Trehalose Permeable to Mammalian Cells. PLoS One 2015; 10:e0130323. [PMID: 26115179 PMCID: PMC4482662 DOI: 10.1371/journal.pone.0130323] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 05/19/2015] [Indexed: 01/09/2023] Open
Abstract
Trehalose is a naturally occurring disaccharide which is associated with extraordinary stress-tolerance capacity in certain species of unicellular and multicellular organisms. In mammalian cells, presence of intra- and extracellular trehalose has been shown to confer improved tolerance against freezing and desiccation. Since mammalian cells do not synthesize nor import trehalose, the development of novel methods for efficient intracellular delivery of trehalose has been an ongoing investigation. Herein, we studied the membrane permeability of engineered lipophilic derivatives of trehalose. Trehalose conjugated with 6 acetyl groups (trehalose hexaacetate or 6-O-Ac-Tre) demonstrated superior permeability in rat hepatocytes compared with regular trehalose, trehalose diacetate (2-O-Ac-Tre) and trehalose tetraacetate (4-O-Ac-Tre). Once in the cell, intracellular esterases hydrolyzed the 6-O-Ac-Tre molecules, releasing free trehalose into the cytoplasm. The total concentration of intracellular trehalose (plus acetylated variants) reached as high as 10 fold the extracellular concentration of 6-O-Ac-Tre, attaining concentrations suitable for applications in biopreservation. To describe this accumulation phenomenon, a diffusion-reaction model was proposed and the permeability and reaction kinetics of 6-O-Ac-Tre were determined by fitting to experimental data. Further studies suggested that the impact of the loading and the presence of intracellular trehalose on cellular viability and function were negligible. Engineering of trehalose chemical structure rather than manipulating the cell, is an innocuous, cell-friendly method for trehalose delivery, with demonstrated potential for trehalose loading in different types of cells and cell lines, and can facilitate the wide-spread application of trehalose as an intracellular protective agent in biopreservation studies.
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Affiliation(s)
- Alireza Abazari
- The Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, Massachusetts, United States of America
| | - Labros G. Meimetis
- The Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Ghyslain Budin
- The Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Shyam Sundhar Bale
- The Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, Massachusetts, United States of America
| | - Ralph Weissleder
- The Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Mehmet Toner
- The Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, Massachusetts, United States of America
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24
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Rao W, Huang H, Wang H, Zhao S, Dumbleton J, Zhao G, He X. Nanoparticle-mediated intracellular delivery enables cryopreservation of human adipose-derived stem cells using trehalose as the sole cryoprotectant. ACS APPLIED MATERIALS & INTERFACES 2015; 7:5017-28. [PMID: 25679454 PMCID: PMC4734639 DOI: 10.1021/acsami.5b00655] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In this study, pH responsive genipin-cross-linked Pluronic F127-chitosan nanoparticles (GNPs) was synthesized to encapsulate trehalose for intracellular delivery to cryopreserve primary human adipose-derived stem cells (hADSCs). Trehalose is a disaccharide of glucose used by lower organisms to survive extreme cold in nature and has been used to cryopreserve various biomacromolecules. However, it does not enter mammalian cells because of its highly hydrophilic nature, and has only been used in combination with other cell-penetrating cryoprotectants (such as dimethyl sulfoxide, DMSO) to cryopreserve mammalian cells. Our data show that trehalose can be efficiently encapsulated in our GNPs for intracellular delivery, which enables cryopreservation of primary hADSCs using the nontoxic sugar as the sole cryoprotectant. This capability is important because the conventional approach of cryopreserving mammalian cells using highly toxic (at body temperature) cell-penetrating cryoprotectants requires multistep washing of the cryopreserved cells to remove the toxic cryoprotectant for further use, which is time-consuming and associated with significant cell loss (∼10% during each washing step). By contrast, the trehalose-cryopreserved cells can be used without washing, which should greatly facilitate the wide application of the burgeoning cell-based medicine.
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Affiliation(s)
- Wei Rao
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, US
- Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA
| | - Haishui Huang
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, US
- Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA
- Department of Mechanical Engineering, The Ohio State University, Columbus, OH 43210, US
| | - Hai Wang
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, US
- Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA
- Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA
| | - Shuting Zhao
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, US
- Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA
| | - Jenna Dumbleton
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, US
- Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA
| | - Gang Zhao
- Centre for Biomedical Engineering, Department of Electronic Science and Technology, University of Science and Technology of China, Hefei, Anhui 230027, China
| | - Xiaoming He
- Department of Biomedical Engineering, The Ohio State University, Columbus, OH 43210, US
- Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA
- Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA
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25
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Ben-Dov N, Korenstein R. The uptake of HIV Tat peptide proceeds via two pathways which differ from macropinocytosis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1848:869-77. [PMID: 25542781 DOI: 10.1016/j.bbamem.2014.12.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Revised: 11/16/2014] [Accepted: 12/16/2014] [Indexed: 12/20/2022]
Abstract
Cell penetrating peptides (CPPs) have been extensively studied as vectors for cellular delivery of therapeutic molecules, yet the identity of their uptake routes remained unclear and is still under debate. In this study we provide new insights into CPP entry routes by quantitatively measuring the intracellular uptake of FAM-labeled Tat-peptide under rigorous kinetic and thermal conditions. The uptake of Tat-peptide between 4 and 15°C corresponds to Q10=1.1, proceeding through a prompt (<5 min), temperature-independent process, suggesting direct membrane translocation. At longer durations, Tat rate of uptake shows linear dependence on temperature with Q10=1.44, accompanied by activation energy Ea=4.45 Kcal/mole. These values are significantly lower than those we found for the macropinocytosis probe dextran (Q10=2.2 and Ea=7.2 Kcal/mole) which possesses an exponential dependence on temperature, characteristic of endocytosis processes. Tat-peptide and dextran do not interfere with each other's uptake rate and the ratio of Tat-peptide uptake to its extracellular concentration is ~15 times higher than that for dextran. In addition, Phloretin, a modulator of cell membrane dipole potential, is shown to increase dextran uptake but to reduce that of Tat. We conclude that the uptake of Tat differs from that of dextran in all parameters. Tat uptake proceeds by dual entry routes which differ by their energy dependence.
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Affiliation(s)
- Nadav Ben-Dov
- Department of Physiology and Pharmacology, Faculty of Medicine, Tel-Aviv University, 69978 Tel-Aviv, Israel.
| | - Rafi Korenstein
- Department of Physiology and Pharmacology, Faculty of Medicine, Tel-Aviv University, 69978 Tel-Aviv, Israel.
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26
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Pisco AO, Jackson DA, Huang S. Reduced Intracellular Drug Accumulation in Drug-Resistant Leukemia Cells is Not Only Solely Due to MDR-Mediated Efflux but also to Decreased Uptake. Front Oncol 2014; 4:306. [PMID: 25401091 PMCID: PMC4215691 DOI: 10.3389/fonc.2014.00306] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 10/15/2014] [Indexed: 12/18/2022] Open
Abstract
Expression of ABC family transporter proteins that promote drug efflux from cancer cells is a widely observed mechanism of multi-drug resistance of cancer cells. Cell adaptation in long-term culture of HL60 leukemic cells in the presence of chemotherapy leads to induction and maintenance of the ABC transporters expression, preventing further accumulation of drugs. However, we found that decreased accumulation of drugs and fluorescent dyes also contributed by a reduced uptake by the resistant cells. Confocal time-lapse microscopy and flow cytometry revealed that fluid-phase endocytosis was diminished in drug-resistant cells compared to drug-sensitive cells. Drug uptake was increased by insulin co-treatment when cells were grown in methylcellulose and monitored under the microscope, but not when cultured in suspension. We propose that multi-drug resistance is not only solely achieved by enhanced efflux capacity but also by supressed intake of the drug, offering an alternative target to overcome drug resistance or potentiate chemotherapy.
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Affiliation(s)
- Angela Oliveira Pisco
- Institute for Systems Biology , Seattle, WA , USA ; Faculty of Life Sciences, University of Manchester , Manchester , UK
| | | | - Sui Huang
- Institute for Systems Biology , Seattle, WA , USA ; Department of Biological Sciences, University of Calgary , Calgary, AB , Canada
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27
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Qu B, Gu Y, Shen J, Qin J, Bao J, Hu Y, Zeng W, Dong W. Trehalose maintains vitality of mouse epididymal epithelial cells and mediates gene transfer. PLoS One 2014; 9:e92483. [PMID: 24651491 PMCID: PMC3961358 DOI: 10.1371/journal.pone.0092483] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 02/24/2014] [Indexed: 11/20/2022] Open
Abstract
In the present study, trehalose was utilized to improve primary culture of mouse epididymal epithelial cells in vitro, and to enhance naked DNA delivery in epididymis in vivo. During the six-day culture, the proliferation activity of the cells in the medium with addition of trehalose was higher than that of those cells cultured in absence of trehalose (p<0.01). To determine the optimal concentration for cell proliferation, a series of trehalose concentrations (0, 60, 120, 180 mM) were tested, and the result indicated that the cell in the medium with 120 mM trehalose showed the highest proliferation potential. The epididymis epithelial cells were cultured in the medium containing 120 mM trehalose upon 16th passage, and they continued expressing markers of epididymal epithelial cell, such as rE-RABP, AR and ER-beta. Our study also indicated that trehalose concentrations of 120–240 mM, especially 180 mM, could effectively enhance DNA delivery into the mouse epididymis epithelial cell in vitro. Moreover, trehalose could induce in vivo expression of exogenous DNA in epididymal epithelial cells and help to internalize plasmid into sperm,which did not influence motility of sperm when the mixture of trehalose (180 mM) and DNA was injected into epididymal lumen through efferent tubule. This study suggested that trehalose, as an effective and safer reagent, could be employed potentially to maintain vitality of mouse epididymal epthetial cells during long-term culture in vitro and to mediate in vitro and in vivo gene transfer.
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Affiliation(s)
- Bin Qu
- College of Animal Science and Technology, Northwest A & F University, Yangling, Shaanxi, P. R. China
| | - Yihua Gu
- Shanghai Institute of Planned Parenthood Research, Shanghai, P. R. China
| | - Jian Shen
- College of Animal Science and Technology, Northwest A & F University, Yangling, Shaanxi, P. R. China
| | - Jinzhou Qin
- College of Animal Science and Technology, Northwest A & F University, Yangling, Shaanxi, P. R. China
| | - Jianqiang Bao
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Yuan Hu
- College of Animal Science and Technology, Northwest A & F University, Yangling, Shaanxi, P. R. China
| | - Wenxian Zeng
- College of Animal Science and Technology, Northwest A & F University, Yangling, Shaanxi, P. R. China
| | - Wuzi Dong
- College of Animal Science and Technology, Northwest A & F University, Yangling, Shaanxi, P. R. China
- * E-mail:
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Ben-Dov N, Korenstein R. Proton-induced endocytosis is dependent on cell membrane fluidity, lipid-phase order and the membrane resting potential. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:2672-81. [PMID: 23911577 DOI: 10.1016/j.bbamem.2013.07.027] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 07/20/2013] [Accepted: 07/22/2013] [Indexed: 01/13/2023]
Abstract
Recently it has been shown that decreasing the extracellular pH of cells stimulates the formation of inward membrane invaginations and vesicles, accompanied by an enhanced uptake of macromolecules. This type of endocytosis was coined as proton-induced uptake (PIU). Though the initial induction of inward membrane curvature was rationalized in terms of proton-based increase of charge asymmetry across the membrane, the dependence of the phenomenon on plasma membrane characteristics is still unknown. The present study shows that depolarization of the membrane resting potential elevates PIU by 25%, while hyperpolarization attenuates it by 25%. Comparison of uptake in suspended and adherent cells implicates that the resting-potential affects PIU through remodeling the actin-cytoskeleton. The pH at the external interface of the cell membrane rather than the pH gradient across it determines the extent of PIU. PIU increases linearly upon temperature increase in the range of 4-36°C, in correlation with the membrane fluidity. The plasma membrane fluidity and the lipid phase order are modulated by enriching the cell's membrane with cholesterol, tergitol, dimethylsulfoxide, 6-ketocholestanol and phloretin and by cholesterol depletion. These treatments are shown to alter the extent of PIU and are better correlated with membrane fluidity than with the lipid phase order. We suggest that the lipid phase order and fluidity influence PIU by regulating the lipid order gradient across the perimeter of the lipid-condensed microdomains (rafts) and alter the characteristic tension line that separates the higher ordered lipid-domains from the lesser ordered ones.
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Affiliation(s)
- Nadav Ben-Dov
- Department of Physiology and Pharmacology, Faculty of Medicine, Tel-Aviv University, 69978 Tel-Aviv, Israel.
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29
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Tapia IJ, Aris M, Arriaga JM, Blanco PA, Mazzobre F, Vega J, Mordoh J, Barrio MM. Development of a novel methodology for cryopreservation of melanoma cells applied to CSF470 therapeutic vaccine. Cryobiology 2013; 67:163-9. [PMID: 23850827 DOI: 10.1016/j.cryobiol.2013.06.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Revised: 06/28/2013] [Accepted: 06/28/2013] [Indexed: 01/20/2023]
Abstract
CSF470 vaccine is a mixture of four lethally irradiated melanoma cell lines, administered with BCG and GM-CSF, which is currently being tested in a Phase II/III Clinical trial in stage II/III melanoma patients. To prepare vaccine doses, irradiated melanoma cell lines are frozen using dimethyl sulfoxide (Me(2)SO) and stored in liquid nitrogen (liqN(2)). Prior to inoculation, doses must be thawed, washed to remove Me(2)SO and suspended for clinical administration. Avoiding the use of Me(2)SO and storage in liqN(2) would allow future freeze-drying of CSF470 vaccine to facilitate pharmaceutical production and distribution. We worked on the development of an alternative cryopreservation methodology while keeping the vaccine's biological and immunogenic properties. We tested different freezing media containing trehalose suitable to remain as excipients in a freeze-dried product, to cryopreserve melanoma cells either before or after gamma irradiation. Melanoma cells incorporated trehalose after 5 h incubation at 37°C by fluid-phase endocytosis, reaching an intracellular concentration that varied between 70-140 mM depending on the cell line. Optimal freezing conditions were 0.2 M trehalose and 30 mg/ml human serum albumin, at -84°C. Vaccine doses could be frozen in trehalose at -84°C for at least four months keeping their cellular integrity, antigen expression and apoptosis/necrosis profile after gamma-irradiation as compared to Me(2)SO control. Non-irradiated melanoma cell lines also showed comparable proliferative capacity after both cryopreservation procedures. Trehalose-freezing medium allowed us to cryopreserve melanoma cells, either alive or after gamma irradiation, at -84°C avoiding the use of Me(2)SO and liqN(2) storage. These cryopreservation conditions could be suitable for future freeze-drying of CSF470 vaccine.
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Affiliation(s)
- Ivana J Tapia
- Centro de Investigaciones Oncológicas FUCA, Crámer 1180, Primer Piso, CP1426, Ciudad Autónoma de Buenos Aires, Argentina
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30
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Relogio P, Bathfield M, Haftek-Terreau Z, Beija M, Favier A, Giraud-Panis MJ, D'Agosto F, Mandrand B, Farinha JPS, Charreyre MT, Martinho JMG. Biotin-end-functionalized highly fluorescent water-soluble polymers. Polym Chem 2013. [DOI: 10.1039/c3py00059a] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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31
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Harrington JM, Scelsi C, Hartel A, Jones NG, Engstler M, Capewell P, MacLeod A, Hajduk S. Novel African trypanocidal agents: membrane rigidifying peptides. PLoS One 2012; 7:e44384. [PMID: 22970207 PMCID: PMC3436892 DOI: 10.1371/journal.pone.0044384] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 08/03/2012] [Indexed: 11/21/2022] Open
Abstract
The bloodstream developmental forms of pathogenic African trypanosomes are uniquely susceptible to killing by small hydrophobic peptides. Trypanocidal activity is conferred by peptide hydrophobicity and charge distribution and results from increased rigidity of the plasma membrane. Structural analysis of lipid-associated peptide suggests a mechanism of phospholipid clamping in which an internal hydrophobic bulge anchors the peptide in the membrane and positively charged moieties at the termini coordinate phosphates of the polar lipid headgroups. This mechanism reveals a necessary phenotype in bloodstream form African trypanosomes, high membrane fluidity, and we suggest that targeting the plasma membrane lipid bilayer as a whole may be a novel strategy for the development of new pharmaceutical agents. Additionally, the peptides we have described may be valuable tools for probing the biosynthetic machinery responsible for the unique composition and characteristics of African trypanosome plasma membranes.
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Affiliation(s)
- John M. Harrington
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Chris Scelsi
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, United States of America
| | - Andreas Hartel
- Department of Cell and Developmental Biology, Theodor-Boveri-Institute, University of Wuerzburg, Wuerzburg, Germany
| | - Nicola G. Jones
- Department of Cell and Developmental Biology, Theodor-Boveri-Institute, University of Wuerzburg, Wuerzburg, Germany
| | - Markus Engstler
- Department of Cell and Developmental Biology, Theodor-Boveri-Institute, University of Wuerzburg, Wuerzburg, Germany
| | - Paul Capewell
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Annette MacLeod
- Wellcome Trust Centre for Molecular Parasitology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Stephen Hajduk
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, United States of America
- * E-mail:
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Zhou J, Zhang C, Liu J, Fan L, Yang L. Loading solution prevents activation damage of human platelets before lyophilization. Cryobiology 2011; 63:229-34. [DOI: 10.1016/j.cryobiol.2011.08.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 08/26/2011] [Accepted: 08/30/2011] [Indexed: 10/17/2022]
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33
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A biophysical model of intracellular distribution and perinuclear accumulation of particulate matter. Biophys Chem 2011; 158:134-40. [DOI: 10.1016/j.bpc.2011.06.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Revised: 06/16/2011] [Accepted: 06/16/2011] [Indexed: 01/15/2023]
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34
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He X. Thermostability of biological systems: fundamentals, challenges, and quantification. Open Biomed Eng J 2011; 5:47-73. [PMID: 21769301 PMCID: PMC3137158 DOI: 10.2174/1874120701105010047] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2010] [Revised: 01/31/2011] [Accepted: 02/01/2011] [Indexed: 12/25/2022] Open
Abstract
This review examines the fundamentals and challenges in engineering/understanding the thermostability of biological systems over a wide temperature range (from the cryogenic to hyperthermic regimen). Applications of the bio-thermostability engineering to either destroy unwanted or stabilize useful biologicals for the treatment of diseases in modern medicine are first introduced. Studies on the biological responses to cryogenic and hyperthermic temperatures for the various applications are reviewed to understand the mechanism of thermal (both cryo and hyperthermic) injury and its quantification at the molecular, cellular and tissue/organ levels. Methods for quantifying the thermophysical processes of the various applications are then summarized accounting for the effect of blood perfusion, metabolism, water transport across cell plasma membrane, and phase transition (both equilibrium and non-equilibrium such as ice formation and glass transition) of water. The review concludes with a summary of the status quo and future perspectives in engineering the thermostability of biological systems.
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Affiliation(s)
- Xiaoming He
- Multiscale Biothermostability Engineering Laboratory, Department of Mechanical Engineering and Biomedical Engineering Program, University of South Carolina, 300 Main Street, Columbia, SC 29208, USA
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35
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Xu MJ, Chen GM, Fan JL, Liu JH, Xu XG, Zhang SZ. Moisture sorption characteristics of freeze-dried human platelets. J Zhejiang Univ Sci B 2011; 12:210-8. [PMID: 21370506 DOI: 10.1631/jzus.b1010199] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Freeze-drying is a promising method for a long-term storage of human platelets. The moisture sorption characteristics of freeze-dried human platelets (FDHPs) were studied in this paper. The moisture sorption isotherms of FDHPs and freeze-dried lyophilization buffer (FDLB) were measured at 4, 25, and 37 °C. The experimental data were fitted to Brunauer-Emmett-Teller (BET) and Guggenheim-Anderson-de Boer (GAB) equations. There were no significant statistical differences (P>0.05) between the sorption characteristics of FDHPs and FDLB at 4 and 25 °C, while FDHPs absorbed more water at 37 °C. The net isosteric heat of sorption was derived. The heat for FDHPs showed an abnormal negative value at low moisture contents when 25 and 37 °C data were used. Dynamic sorption experiments were carried out at 25 °C with environmental water activity controlled at 0.75, 0.85, and 0.90. The moisture diffusion coefficient was fitted to be 8.24×10(-12) m(2)/s when experimental data at initial time were used. These results would be helpful in choosing prehydration and storage condition for FDHPs.
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Affiliation(s)
- Meng-jie Xu
- Institute of Refrigeration and Cryogenics, Zhejiang University, Hangzhou 310027, China
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36
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Nowatzki J, de Sene RV, Paludo KS, Veiga SS, Oliver C, Jamur MC, Nader HB, Trindade ES, Franco CRC. Brown spider venom toxins interact with cell surface and are endocytosed by rabbit endothelial cells. Toxicon 2010; 56:535-43. [DOI: 10.1016/j.toxicon.2010.03.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Revised: 02/19/2010] [Accepted: 03/24/2010] [Indexed: 11/25/2022]
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37
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Jiao CY, Delaroche D, Burlina F, Alves ID, Chassaing G, Sagan S. Translocation and endocytosis for cell-penetrating peptide internalization. J Biol Chem 2009; 284:33957-65. [PMID: 19833724 DOI: 10.1074/jbc.m109.056309] [Citation(s) in RCA: 248] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cell-penetrating peptides (CPPs) share the property of cellular internalization. The question of how these peptides reach the cytoplasm of cells is still widely debated. Herein, we have used a mass spectrometry-based method that enables quantification of internalized and membrane-bound peptides. Internalization of the most used CPP was studied at 37 degrees C (endocytosis and translocation) and 4 degrees C (translocation) in wild type and proteoglycan-deficient Chinese hamster ovary cells. Both translocation and endocytosis are internalization pathways used by CPP. The choice of one pathway versus the other depends on the peptide sequence (not the number of positive changes), the extracellular peptide concentration, and the membrane components. There is no relationship between the high affinity of these peptides for the cell membrane and their internalization efficacy. Translocation occurs at low extracellular peptide concentration, whereas endocytosis, a saturable and cooperative phenomenon, is activated at higher concentrations. Translocation operates in a narrow time window, which implies a specific lipid/peptide co-import in cells.
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Affiliation(s)
- Chen-Yu Jiao
- Laboratoire des Biomolécules, Université Pierre et Marie Curie (Paris 6), 75005 Paris, France
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38
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39
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Zhang W, Rong J, Wang Q, He X. The encapsulation and intracellular delivery of trehalose using a thermally responsive nanocapsule. NANOTECHNOLOGY 2009; 20:275101. [PMID: 19528681 DOI: 10.1088/0957-4484/20/27/275101] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The thermally responsive wall permeability of an empty core-shell structured Pluronic nanocapsule (together with its temperature dependent size and surface charge) was successfully utilized for encapsulation, intracellular delivery, and controlled release of trehalose, a highly hydrophilic small (M(W) = 342 D) molecule (a disaccharide of glucose) that is exceptional for long-term stabilization of biologicals (particularly at ambient temperatures). It was found that trehalose can be physically encapsulated in the nanocapsule using a soaking-freeze-drying-heating procedure. The nanocapsule is capable of physically withholding trehalose with negligible release in hours for cellular uptake at 37 degrees C when its wall permeability is low. A quick release of the encapsulated sugar can be achieved by thermally cycling the nanocapsule between 37 and 22 degrees C (or lower). A significant amount of trehalose (up to 0.3 M) can be delivered into NIH 3T3 fibroblasts by incubating the cells with the trehalose-encapsulated nanocapsules at 37 degrees C for 40 min. Moreover, cytotoxicity of the nanocapsule for the purpose of intracellular delivery of trehalose was found to be negligible. Altogether, the thermally responsive nanocapsule is effective for intracellular delivery of trehalose, which is critical for the long-term stabilization of mammalian cells at ambient temperatures and the eventual success of modern cell-based medicine.
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Affiliation(s)
- Wujie Zhang
- Department of Mechanical Engineering, University of South Carolina, 300 Main Street, Columbia, SC 29208, USA
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40
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The Influence of Membrane Lipids in Staphylococcus aureus Gamma-Hemolysins Pore Formation. J Membr Biol 2008; 227:13-24. [DOI: 10.1007/s00232-008-9140-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Accepted: 11/05/2008] [Indexed: 01/18/2023]
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41
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Roles of membrane structure and phase transition on the hyperosmotic stress survival of Geobacter sulfurreducens. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1778:2283-90. [DOI: 10.1016/j.bbamem.2008.06.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2008] [Revised: 05/23/2008] [Accepted: 06/09/2008] [Indexed: 11/23/2022]
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42
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Abstract
Trehalose metabolism and signaling is an area of emerging significance. In less than a decade our views on the importance of trehalose metabolism and its role in plants have gone through something of a revolution. An obscure curiosity has become an indispensable regulatory system. Mutant and transgenic plants of trehalose synthesis display wide-ranging and unprecedented phenotypes for the perturbation of a metabolic pathway. Molecular physiology and genomics have provided a glimpse of trehalose biology that had not been possible with conventional techniques, largely because the products of the synthetic pathway, trehalose 6-phosphate (T6P) and trehalose, are in trace abundance and difficult to measure in most plants. A consensus is emerging that T6P plays a central role in the coordination of metabolism with development. The discovery of trehalose metabolism has been one of the most exciting developments in plant metabolism and plant science in recent years. The field is fast moving and this review highlights the most recent insights.
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Affiliation(s)
- Matthew J Paul
- Center for Crop Genetic Improvement, Rothamsted Research, Harpenden, Hertfordshire, AL5 2JQ, United Kingdom.
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43
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Hammer MM, Wehrman TS, Blau HM. A novel enzyme complementation-based assay for monitoring G-protein-coupled receptor internalization. FASEB J 2007; 21:3827-34. [PMID: 17942829 DOI: 10.1096/fj.07-8777com] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
G-protein-coupled receptor (GPCR) signaling is involved in a wide range of physiological processes and diseases, and around one-half of currently used drugs target GPCRs. Assays for the signaling of GPCRs have suffered from drawbacks, including low signal-to-noise, temporally transient signals, and difficulty in applying a single assay to a wide range of GPCRs. We have developed a set of assays for G-protein-coupled receptor signaling based on beta-galactosidase enzyme complementation in live mammalian cells. We previously described an assay for GPCR activation by monitoring the binding of beta-arrestin to the receptor. Here we describe a second assay that monitors the internalization of GPCRs to endosomes, an event that follows receptor activation and is critical in desensitizing and resensitizing the receptor. We show that both assays display high signal-to-noise ratios with low variability and are quantitative for a wide range of GPCRs. EC50s obtained with these assays closely match results reported in the literature. Finally, we show that these assays are readily adapted to high-throughput chemical screens. Thus, these two assays for monitoring G-protein-coupled receptor activation and internalization should prove valuable in basic biological studies as well as in high-throughput screens.
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Affiliation(s)
- Mark M Hammer
- Baxter Laboratory in Genetic Pharmacology, Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305-5175, USA
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44
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Simonin H, Beney L, Gervais P. Sequence of occurring damages in yeast plasma membrane during dehydration and rehydration: mechanisms of cell death. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2007; 1768:1600-10. [PMID: 17466936 DOI: 10.1016/j.bbamem.2007.03.017] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2007] [Revised: 03/15/2007] [Accepted: 03/16/2007] [Indexed: 02/01/2023]
Abstract
Yeasts are often exposed to variations in osmotic pressure in their natural environments or in their substrates when used in fermentation industries. Such changes may lead to cell death or activity loss. Although the involvement of the plasma membrane is strongly suspected, the mechanism remains unclear. Here, the integrity and functionality of the yeast plasma membrane at different levels of dehydration and rehydration during an osmotic treatment were assessed using various fluorescent dyes. Flow cytometry and confocal microscopy of cells stained with oxonol, propidium iodide, and lucifer yellow were used to study changes in membrane polarization, permeabilization, and endocytosis, respectively. Cell volume contraction, reversible depolarization, permeabilization, and endovesicle formation were successively observed with increasing levels of osmotic pressure during dehydration. The maximum survival rate was also detected at a specific rehydration level, of 20 MPa, above which cells were strongly permeabilized. Thus, we show that the two steps of an osmotic treatment, dehydration and rehydration, are both involved in the induction of cell death. Permeabilization of the plasma membranes is the critical event related to cell death. It may result from lipidic phase transitions in the membrane and from variations in the area-to-volume ratio during the osmotic treatment.
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Affiliation(s)
- Hélène Simonin
- Laboratoire de Génie des Procédés Alimentaires et Biotechnologiques ENSBANA-1, Esplanade Erasme-21000 DIJON, France
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45
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Ménez C, Buyse M, Farinotti R, Barratt G. Inward Translocation of the Phospholipid Analogue Miltefosine across Caco-2 Cell Membranes Exhibits Characteristics of a Carrier-mediated Process. Lipids 2007; 42:229-40. [PMID: 17393228 DOI: 10.1007/s11745-007-3026-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2006] [Accepted: 01/09/2007] [Indexed: 10/23/2022]
Abstract
Miltefosine (hexadecylphosphocholine, HePC) is the first effective oral agent for the treatment of visceral leishmaniasis. The characteristics of HePC incorporation into the human intestinal epithelial cell line Caco-2 were investigated in order to understand its oral absorption mechanism. The results provide evidence for the involvement of a carrier-mediated mechanism, since the association of HePC at the apical pole of Caco-2 cells was (1) saturable as a function of time with a rapid initial incorporation over 5 min followed by a more gradual increase; (2) saturable as a function of concentration over the range studied (2-200 microM) with a saturable component which followed Michaelis-Menten kinetics (apparent K (m) 15.7 micromol/L, V (max) 39.2 nmol/mg protein/h) and a nonspecific diffusion component; (3) partially inhibited by low temperature and ATP depletion, indicating the temperature and energy-dependence of the uptake process. Moreover, we demonstrated, by an albumin back-extraction method, that HePC is internalized via translocation from the outer to the inner leaflet of the plasma membrane and that HePC may preferentially diffuse through intact raft microdomains. In conclusion, our results suggest that incorporation of HePC at the apical membrane of Caco-2 cells may occur through a passive diffusion followed by a translocation in the inner membrane leaflet through an active carrier-mediated mechanism.
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Affiliation(s)
- Cécile Ménez
- Laboratoire de Physico-chimie, Pharmacotechnie et Biopharmacie, UMR CNRS 8612 Faculté de Pharmacie, Univ. Paris-Sud 11, IFR 141, Tour D5, 2éme étage, 5 rue J.B. Clément, Châtenay-Malabry, Cedex 92296, France
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46
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Zieger MAJ, Gupta MP. Endothelial cell preservation at 10 degrees C minimizes catalytic iron, oxidative stress, and cold-induced injury. Cell Transplant 2007; 15:499-510. [PMID: 17121161 DOI: 10.3727/000000006783981756] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
There is growing evidence that oxidative stress plays an important role in mediating the injury induced by hypothermia during the preservation of cells and tissues for clinical or research use. In cardiovascular allografts, endothelial cell loss or injury may lead to impaired control of vascular permeability and tone, thrombosis, and inflammation. We hypothesized that hypothermia-induced damage to the endothelium is linked to increases in intracellular catalytic iron pools and oxidative stress. In this study, bovine aortic endothelial cells and cell culture methods were used to model the response of the endothelium of cardiovascular tissues to hypothermia. Confluent cells were stored at 0 degrees C to 25 degrees C and cell damage was measured by lipid peroxidation (LPO) and lactate dehydrogenase release. Varying the bleomycin-detectible iron (BDI) in cells modulated cold-induced LPO and cell injury. In untreated cells, injury was highest at 0 degrees C and a minimum at 10 degrees C. A similar temperature-dependent trend was found in BDI levels and cell plating efficiencies. Arrhenius plots of cell killing and iron accumulation rates showed biphasic temperature dependence, with minima at 10 degrees C and matching activation energies above and below 10 degrees C. These findings imply that the mechanisms underlying the hypothermic increase in catalytic iron, oxidative stress, and cell killing are the same and that preservation of the endothelium may be optimized at temperatures above those routinely used.
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Affiliation(s)
- Michael A J Zieger
- Methodist Research Institute, Clarian Health Partners, Inc., Indianapolis, IN 46202, USA.
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47
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Sarkar S, Davies JE, Huang Z, Tunnacliffe A, Rubinsztein DC. Trehalose, a novel mTOR-independent autophagy enhancer, accelerates the clearance of mutant huntingtin and alpha-synuclein. J Biol Chem 2006; 282:5641-52. [PMID: 17182613 DOI: 10.1074/jbc.m609532200] [Citation(s) in RCA: 835] [Impact Index Per Article: 46.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Trehalose, a disaccharide present in many non-mammalian species, protects cells against various environmental stresses. Whereas some of the protective effects may be explained by its chemical chaperone properties, its actions are largely unknown. Here we report a novel function of trehalose as an mTOR-independent autophagy activator. Trehalose-induced autophagy enhanced the clearance of autophagy substrates like mutant huntingtin and the A30P and A53T mutants of alpha-synuclein, associated with Huntington disease (HD) and Parkinson disease (PD), respectively. Furthermore, trehalose and mTOR inhibition by rapamycin together exerted an additive effect on the clearance of these aggregate-prone proteins because of increased autophagic activity. By inducing autophagy, we showed that trehalose also protects cells against subsequent pro-apoptotic insults via the mitochondrial pathway. The dual protective properties of trehalose (as an inducer of autophagy and chemical chaperone) and the combinatorial strategy with rapamycin may be relevant to the treatment of HD and related diseases, where the mutant proteins are autophagy substrates.
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Affiliation(s)
- Sovan Sarkar
- Department of Medical Genetics, Cambridge Institute for Medical Research, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge CB2 2XY, United Kingdom
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48
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Norris MM, Aksan A, Sugimachi K, Toner M. 3-O-methyl-D-glucose improves desiccation tolerance of keratinocytes. ACTA ACUST UNITED AC 2006; 12:1873-9. [PMID: 16889517 DOI: 10.1089/ten.2006.12.1873] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Transplantation of autologous skin grafts and tissue engineered skin replacements for the treatment of burns, trauma, and ulcerative wounds has been shown to restore a protective barrier to infection and fluid loss, reduce heat loss, provide mechanical strength, diminish pain, and dampen the hypermetabolic stress response to thermal injury. Patencies of these grafts depend mainly on the high viability and sustained function of the enmeshed keratinocytes. With growing demand in tissue replacement therapies, development of successful and economical preservation techniques for skin grafts and replacements becomes essential. In this regard, if attained, desiccated state storage offers an economical solution to availability, storage, and transportation problems. Recent studies indicate that carbohydrates are very efficient in stabilizing mammalian cells against various types of stresses, including those associated with cryopreservation and desiccation. In this study we introduce the use of 3-O-methyl-D-glucose (3-OMG), a nonmetabolizable glucose derivative, as a new means of providing protection for keratinocytes undergoing desiccation. We show that with decreasing water contents, viability of the cells decreases; however, at the same water content the immediate post-rehydration viability and long-term survival of the cells exposed to 3-OMG are much higher than those of controls.
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Affiliation(s)
- Marlaina M Norris
- Surgical Services and Center for Engineering in Medicine, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Boston, Massachusetts 02114, USA
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He X, Amin AA, Fowler A, Toner M. Thermally Induced Introduction of Trehalose into Primary Rat Hepatocytes. ACTA ACUST UNITED AC 2006. [DOI: 10.1089/cpt.2006.4.178] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Xiaoming He
- Center for Engineering in Medicine and Surgery Services, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Arthi A. Amin
- Center for Engineering in Medicine and Surgery Services, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
| | - Alex Fowler
- Department of Mechanical Engineering, University of Massachusetts at Dartmouth, North Dartmouth, Massachusetts
| | - Mehmet Toner
- Center for Engineering in Medicine and Surgery Services, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
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50
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Lambot N, Lybaert P, Boom A, Delogne-Desnoeck J, Vanbellinghen AM, Graff G, Lebrun P, Meuris S. Evidence for a Clathrin-Mediated Recycling of Albumin in Human Term Placenta1. Biol Reprod 2006; 75:90-7. [PMID: 16495477 DOI: 10.1095/biolreprod.105.050021] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
During human pregnancy, the trophoblast layer is in direct contact with maternal albumin. In contrast to immunoglobulins, albumin does not cross the placental barrier. However, albumin affects the trophoblast placental lactogen and chorionic gonadotroph secretion. The present study investigated the interaction between albumin and syncytiotrophoblast using human term placental explants. Bovine serum albumin, labeled with either 125I or fluorescein isothio-cyanate, was taken up rapidly by placental explants. This process was temperature-sensitive. The internalized labeled BSA quickly outflowed from the tissue at the maternal side, largely without any major modification in molecular weight. Colchicine (1 mM), which disrupts the microtubule network, or cytochalasin B (40 microM), which disassembles filamentous actin, did not interfere with the placental transmembrane movements of labeled BSA. Megalin, clathrin, and caveolin 1 are three membrane proteins associated with albumin endocytosis in other tissues, but only megalin and clathrin were detected in the syncytiotrophoblast layer by immunohistochemistry. The uptake of labeled BSA into placental explants was not modified by 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (1 mM) or 5-nitro-2-(3-phenylpropylamino)benzoic acid (100 microM), two pharmacological tools known to disturb megalin-mediated albumin endocytosis. By contrast, methyl-beta-cyclodextrin (10 mM) and chlorpromazine (1.4 mM), both of which disrupt the clathrin-mediated endocytotic system, significantly reduced the uptake of labeled BSA. These data suggest, to our knowledge for the first time, that maternal albumin is actively internalized into the human trophoblast according to an apical recycling pathway. This temperature-sensitive process does not depend on an intact cytoskeleton, but it is associated with a clathrin-mediated endocytotic system.
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Affiliation(s)
- N Lambot
- Laboratory of Experimental Hormonology, Université Libre de Bruxelles, B-1070 Brussels, Belgium.
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