1
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Gee S, Glover KJ, Wittenberg NJ, Im W. CHARMM-GUI Membrane Builder for Lipid Droplet Modeling and Simulation. Chempluschem 2024:e202400013. [PMID: 38600039 DOI: 10.1002/cplu.202400013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 04/02/2024] [Accepted: 04/10/2024] [Indexed: 04/12/2024]
Abstract
Lipid droplets (LDs) are organelles that are necessary for eukaryotic and prokaryotic metabolism and energy storage. They have a unique structure consisting of a spherical phospholipid monolayer encasing neutral lipids such as triacylglycerol (TAG). LDs have garnered increased interest for their implications in disease and for drug delivery applications. Consequently, there is an increased need for tools to study their structure, composition, and dynamics in biological contexts. In this work, we utilize CHARMM-GUI Membrane Builder to simulate and analyze LDs with and without a plant LD protein, oleosin. The results show that Membrane Builder can generate biologically relevant all-atom LD systems with relatively short equilibration times using a new TAG library having optimized headgroup parameters. TAG molecules originally inserted into a lipid bilayer aggregate in the membrane center, forming a TAG-only core flanked by two monolayers. The TAG-only core thickness stably grows with increasing TAG mole fraction. A 70% TAG system has a core that is thick enough to house oleosin without its interactions with the distal leaflet or disruption of its secondary structure. We hope that Membrane Builder can aid in the future study of LD systems, including their structure and dynamics with and without proteins.
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Affiliation(s)
- Stephen Gee
- Lehigh University, Bioengineering, UNITED STATES
| | | | | | - Wonpil Im
- Lehigh University, 111 Research Drive, UNITED STATES
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2
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Brown TP, Santa DE, Berger BA, Kong L, Wittenberg NJ, Im W. CHARMM GUI Membrane Builder for oxidized phospholipid membrane modeling and simulation. Curr Opin Struct Biol 2024; 86:102813. [PMID: 38598982 DOI: 10.1016/j.sbi.2024.102813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 03/14/2024] [Accepted: 03/21/2024] [Indexed: 04/12/2024]
Abstract
Oxidative stress leads to the production of oxidized phospholipids (oxPLs) that modulate the biophysical properties of phospholipid monolayers and bilayers. As many immune cells are responsible for surveilling cells and tissues for the presence of oxPLs, oxPL-dependent mechanisms have been suggested as targets for treating chronic kidney disease, atherosclerosis, diabetes, and cancer metastasis. This review details recent experimental and computational studies that characterize oxPLs' behaviors in various monolayers and bilayers. These studies investigate how the tail length and polar functional groups of OxPLs impact membrane properties, how oxidized membranes can be stabilized, and how membrane integrity is generally affected by oxidized lipids. In addition, for oxPL-containing membrane modeling and simulation, CHARMM-GUI Membrane Builder has been extended to support a variety of oxPLs, accelerating the simulation system building process for these biologically relevant lipid bilayers.
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Affiliation(s)
- Turner P Brown
- Department of Bioengineering, Lehigh University, Bethlehem, PA 18015, USA
| | - Dane E Santa
- Department of Chemistry, Lehigh University, Bethlehem, PA 18015, USA
| | - Brett A Berger
- Department of Chemistry, Lehigh University, Bethlehem, PA 18015, USA
| | - Lingyang Kong
- Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015, USA
| | | | - Wonpil Im
- Department of Bioengineering, Lehigh University, Bethlehem, PA 18015, USA; Department of Chemistry, Lehigh University, Bethlehem, PA 18015, USA; Department of Biological Sciences, Lehigh University, Bethlehem, PA 18015, USA.
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3
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Cawley J, Berger BA, Odudimu AT, Singh AN, Santa DE, McDarby AI, Honerkamp-Smith AR, Wittenberg NJ. Imaging Giant Vesicle Membrane Domains with a Luminescent Europium Tetracycline Complex. ACS Omega 2023; 8:29314-29323. [PMID: 37599986 PMCID: PMC10433515 DOI: 10.1021/acsomega.3c02721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 07/24/2023] [Indexed: 08/22/2023]
Abstract
Microdomains in lipid bilayer membranes are routinely imaged using organic fluorophores that preferentially partition into one of the lipid phases, resulting in fluorescence contrast. Here, we show that membrane microdomains in giant unilamellar vesicles (GUVs) can be visualized with europium luminescence using a complex of europium III (Eu3+) and tetracycline (EuTc). EuTc is unlike typical organic lipid probes in that it is a coordination complex with a unique excitation/emission wavelength combination (396/617 nm), a very large Stokes shift (221 nm), and a very narrow emission bandwidth (8 nm). The probe preferentially interacts with liquid disordered domains in GUVs, which results in intensity contrast across the surface of phase-separated GUVs. Interestingly, EuTc also alters GM1 ganglioside partitioning. GM1 typically partitions into liquid ordered domains, but after labeling phase-separated GUVs with EuTc, cholera toxin B-subunit (CTxB), which binds GM1, labels liquid disordered domains. We also demonstrate that EuTc, but not free Eu3+ or Tc, significantly reduces lipid diffusion coefficients. Finally, we show that EuTc can be used to label cellular membranes similar to a traditional membrane probe. EuTc may find utility as a membrane imaging probe where its large Stokes shift and sharp emission band would enable multicolor imaging.
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Affiliation(s)
- Jennie
L. Cawley
- Department
of Chemistry, Lehigh University, 6 East Packer Avenue, Bethlehem, Pennsylvania 18015, United States
| | - Brett A. Berger
- Department
of Chemistry, Lehigh University, 6 East Packer Avenue, Bethlehem, Pennsylvania 18015, United States
| | - Adeyemi T. Odudimu
- Department
of Chemistry, Lehigh University, 6 East Packer Avenue, Bethlehem, Pennsylvania 18015, United States
| | - Aarshi N. Singh
- Department
of Chemistry, Lehigh University, 6 East Packer Avenue, Bethlehem, Pennsylvania 18015, United States
| | - Dane E. Santa
- Department
of Chemistry, Lehigh University, 6 East Packer Avenue, Bethlehem, Pennsylvania 18015, United States
| | - Ariana I. McDarby
- Department
of Chemistry, Lehigh University, 6 East Packer Avenue, Bethlehem, Pennsylvania 18015, United States
| | - Aurelia R. Honerkamp-Smith
- Department
of Physics, Lehigh University, 17 Memorial Drive East, Bethlehem, Pennsylvania 18015, United States
| | - Nathan J. Wittenberg
- Department
of Chemistry, Lehigh University, 6 East Packer Avenue, Bethlehem, Pennsylvania 18015, United States
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4
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Singh AN, Nice JB, Brown AC, Wittenberg NJ. Identifying size-dependent toxin sorting in bacterial outer membrane vesicles. bioRxiv 2023:2023.05.03.539273. [PMID: 37205353 PMCID: PMC10187208 DOI: 10.1101/2023.05.03.539273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Gram-negative bacteria produce outer membrane vesicles (OMVs) that play a critical role in cell-cell communication and virulence. Despite being isolated from a single population of bacteria, OMVs can exhibit heterogeneous size and toxin content, which can be obscured by assays that measure ensemble properties. To address this issue, we utilize fluorescence imaging of individual OMVs to reveal size-dependent toxin sorting. Our results showed that the oral bacterium Aggregatibacter actinomycetemcomitans (A.a.) produces OMVs with a bimodal size distribution, where larger OMVs were much more likely to possess leukotoxin (LtxA). Among the smallest OMVs (< 100 nm diameter), the fraction that are toxin positive ranges from 0-30%, while the largest OMVs (> 200 nm diameter) are between 70-100% toxin positive. Our single OMV imaging method provides a non-invasive way to observe OMV surface heterogeneity at the nanoscale level and determine size-based heterogeneities without the need for OMV fraction separation.
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Affiliation(s)
- Aarshi N. Singh
- Department of Chemistry, Lehigh University, Bethlehem, PA, U.S.A
| | - Justin B Nice
- Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA, U.S.A
| | - Angela C. Brown
- Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA, U.S.A
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5
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Cawley J, Wittenberg NJ. Imaging lipid membrane microdomains of giant unilamellar vesicles with europium luminescence. Biophys J 2022. [DOI: 10.1016/j.bpj.2021.11.1660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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6
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Ongwae GM, Chordia MD, Cawley JL, Dalesandro BE, Wittenberg NJ, Pires MM. Targeting of Pseudomonas aeruginosa cell surface via GP12, an Escherichia coli specific bacteriophage protein. Sci Rep 2022; 12:721. [PMID: 35031652 PMCID: PMC8760310 DOI: 10.1038/s41598-021-04627-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 12/28/2021] [Indexed: 11/08/2022] Open
Abstract
Bacteriophages are highly abundant molecular machines that have evolved proteins to target the surface of host bacterial cells. Given the ubiquity of lipopolysaccharides (LPS) on the outer membrane of Gram-negative bacteria, we reasoned that targeting proteins from bacteriophages could be leveraged to target the surface of Gram-negative pathogens for biotechnological applications. To this end, a short tail fiber (GP12) from the T4 bacteriophage, which infects Escherichia coli (E. coli), was isolated and tested for the ability to adhere to whole bacterial cells. We found that, surprisingly, GP12 effectively bound the surface of Pseudomonas aeruginosa cells despite the established preferred host of T4 for E. coli. In efforts to elucidate why this binding pattern was observed, it was determined that the absence of the O-antigen region of LPS on E. coli improved cell surface tagging. This indicated that O-antigens play a significant role in controlling cell adhesion by T4. Probing GP12 and LPS interactions further using deletions of the enzymes involved in the biosynthetic pathway of LPS revealed the inner core oligosaccharide as a possible main target of GP12. Finally, we demonstrated the potential utility of GP12 for biomedical applications by showing that GP12-modified agarose beads resulted in the depletion of pathogenic bacteria from solution.
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Affiliation(s)
- George M Ongwae
- Department of Chemistry, Lehigh University, Bethlehem, PA, 18015, USA
| | - Mahendra D Chordia
- Department of Chemistry, University of Virginia, Charlottesville, VA, 22904, USA
| | - Jennie L Cawley
- Department of Chemistry, Lehigh University, Bethlehem, PA, 18015, USA
| | - Brianna E Dalesandro
- Department of Chemistry, University of Virginia, Charlottesville, VA, 22904, USA
| | | | - Marcos M Pires
- Department of Chemistry, University of Virginia, Charlottesville, VA, 22904, USA.
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7
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Cawley JL, Blauch ME, Collins SM, Nice JB, Xie Q, Jordan LR, Brown AC, Wittenberg NJ. Nanoarrays of Individual Liposomes and Bacterial Outer Membrane Vesicles by Liftoff Nanocontact Printing. Small 2021; 17:e2103338. [PMID: 34655160 PMCID: PMC8678320 DOI: 10.1002/smll.202103338] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 08/27/2021] [Indexed: 06/13/2023]
Abstract
Analytical characterization of small biological particles, such as extracellular vesicles (EVs), is complicated by their extreme heterogeneity in size, lipid, membrane protein, and cargo composition. Analysis of individual particles is essential for illuminating particle property distributions that are obscured by ensemble measurements. To enable high-throughput analysis of individual particles, liftoff nanocontact printing (LNCP) is used to define hexagonal antibody and toxin arrays that have a 425 nm dot size, on average, and 700 nm periodicity. The LNCP process is rapid, simple, and does not require access to specialized nanofabrication tools. These densely packed, highly ordered arrays are used to capture liposomes and bacterial outer membrane vesicles on the basis of their surface biomarkers, with a maximum of one particle per array dot, resulting in densely packed arrays of particles. Despite the high particle density, the underlying antibody or toxin array ensured that neighboring individual particles are optically resolvable. Provided target particle biomarkers and suitable capture molecules are identified, this approach can be used to generate high density arrays of a wide variety of small biological particles, including other types of EVs like exosomes.
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Affiliation(s)
- Jennie L Cawley
- Department of Chemistry, Lehigh University, 6 E Packer Ave, Bethlehem, PA, 18015, USA
| | - Megan E Blauch
- Department of Chemistry, Lehigh University, 6 E Packer Ave, Bethlehem, PA, 18015, USA
| | - Shannon M Collins
- Department of Chemical and Biomolecular Engineering, Lehigh University, 111 Research Drive, Bethlehem, PA, 18015, USA
| | - Justin B Nice
- Department of Chemical and Biomolecular Engineering, Lehigh University, 111 Research Drive, Bethlehem, PA, 18015, USA
| | - Qing Xie
- Department of Chemistry, Lehigh University, 6 E Packer Ave, Bethlehem, PA, 18015, USA
| | - Luke R Jordan
- Department of Chemistry, Lehigh University, 6 E Packer Ave, Bethlehem, PA, 18015, USA
| | - Angela C Brown
- Department of Chemical and Biomolecular Engineering, Lehigh University, 111 Research Drive, Bethlehem, PA, 18015, USA
| | - Nathan J Wittenberg
- Department of Chemistry, Lehigh University, 6 E Packer Ave, Bethlehem, PA, 18015, USA
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8
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Julien JA, Mutchek SG, Wittenberg NJ, Glover KJ. Biophysical characterization of full-length oleosin in dodecylphosphocholine micelles. Proteins 2021; 90:560-565. [PMID: 34596903 DOI: 10.1002/prot.26252] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 09/23/2021] [Accepted: 09/27/2021] [Indexed: 11/07/2022]
Abstract
Oleosin is a hydrophobic protein that punctuates the surface of plant seed lipid droplets, which are 20 nm-100 μm entities that serve as reservoirs for high-energy metabolites. Oleosin is purported to stabilize lipid droplets, but its exact mechanism of stabilization has not been established. Probing the structure of oleosin directly in lipid droplets is challenging due to the size of lipid droplets and their high degree of light scattering. Therefore, a medium in which the native structure of oleosin is retained, but is also amenable to spectroscopic studies is needed. Here, we show, using a suite of biophysical techniques, that dodecylphosphocholine micelles appear to support the tertiary structure of the oleosin protein (i.e., hairpin conformation) and render the protein in an oligomeric state that is amenable to more sophisticated biophysical techniques such as NMR.
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Affiliation(s)
- Jeffrey A Julien
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania, USA
| | - Sarah G Mutchek
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania, USA
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9
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Baxter AM, Jordan LR, Kullappan M, Wittenberg NJ. Tubulation of Supported Lipid Bilayer Membranes Induced by Photosensitized Lipid Oxidation. Langmuir 2021; 37:5753-5762. [PMID: 33939441 DOI: 10.1021/acs.langmuir.0c03363] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We show that photosensitized phospholipid oxidation, initiated by the lipid-conjugated fluorophore TopFluor-PC, causes defects, namely, membrane tubes and vesicle-like structures, in supported lipid bilayers (SLBs). Lipid oxidation is detrimental to the integrity of the lipid molecules; when oxidized, they undergo a conformational expansion, which causes membrane tubes to protrude from the SLB. Lipid oxidation is verified by FT-IR spectroscopy, and area expansion is observed in Langmuir trough experiments. Upon growing to a critical length, the membrane tubes arising from SLBs rapidly undergo transition to vesicle-like structures. We find a correlation between the maximum tube length and the diameter of the resulting vesicle, suggesting the conservation of the surface area between these features. We use geometric modeling and the measured tube length and vesicle radius to calculate the tube radius; our calculated mean tube diameter of 243 nm is comparable to other groups' experimental findings. In the presence of fluid flow, membrane tubes can be extended to tens to hundreds of microns in length. SLBs composed of saturated lipids resist light-induced tubulation, and the inclusion of the lipophilic antioxidant α-tocopherol attenuates the tubulation process and increases the light intensity threshold for tubulation.
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Affiliation(s)
- Ashley M Baxter
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Luke R Jordan
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Monicka Kullappan
- Department of Chemical & Biomolecular Engineering, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Nathan J Wittenberg
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
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10
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Julien JA, Pellett AL, Shah SS, Wittenberg NJ, Glover KJ. Preparation and characterization of neutrally-buoyant oleosin-rich synthetic lipid droplets. Biochim Biophys Acta Biomembr 2021; 1863:183624. [PMID: 33933429 DOI: 10.1016/j.bbamem.2021.183624] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 03/30/2021] [Accepted: 04/08/2021] [Indexed: 01/28/2023]
Abstract
Lipid droplets also known as oil bodies are found in a variety of organisms and function as stores of high-energy metabolites. Recently, there has been interest in using lipid droplets for protein production and drug delivery. Artificial lipid droplets have been previously prepared, but their short lifetime in solution and inhomogeneity has severely limited their applicability. Herein we report an improved methodology for the production of synthetic lipid droplets that overcomes the aforementioned limitations. These advancements include: 1) development of a methodology for the expression and purification of high-levels of oleosin, a crucial lipid droplet component, 2) preparation of neutrally-buoyant synthetic lipid droplets, and 3) production of synthetic lipid droplets of a specific size. Together, these important enhancements will facilitate the advancement of lipid droplet science and its application in biotechnology.
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Affiliation(s)
- Jeffrey A Julien
- Department of Chemistry, Lehigh University, 6 E. Packer Ave. Bethlehem, PA 18015, USA
| | - Alexandria L Pellett
- Department of Chemistry, Lehigh University, 6 E. Packer Ave. Bethlehem, PA 18015, USA
| | - Shivani S Shah
- Department of Chemistry, Lehigh University, 6 E. Packer Ave. Bethlehem, PA 18015, USA
| | - Nathan J Wittenberg
- Department of Chemistry, Lehigh University, 6 E. Packer Ave. Bethlehem, PA 18015, USA
| | - Kerney Jebrell Glover
- Department of Chemistry, Lehigh University, 6 E. Packer Ave. Bethlehem, PA 18015, USA.
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11
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Cawley JL, Jordan LR, Wittenberg NJ. Detection and Characterization of Vesicular Gangliosides Binding to Myelin-Associated Glycoprotein on Supported Lipid Bilayers. Anal Chem 2021; 93:1185-1192. [PMID: 33296186 DOI: 10.1021/acs.analchem.0c04412] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
In the nervous system, a myelin sheath that originates from oligodendrocytes or Schwann cells wraps around axons to facilitate electrical signal transduction. The interface between an axon and myelin is maintained by a number of biomolecular interactions. Among the interactions are those between GD1a and GT1b gangliosides on the axon and myelin-associated glycoprotein (MAG) on myelin. Interestingly, these interactions can also inhibit neuronal outgrowth. Ganglioside-MAG interactions are often studied in cellular or animal models where their relative concentrations are not easily controlled or in assays where the gangliosides and MAG are not presented as part of fluid lipid bilayers. Here, we present an approach to characterize MAG-ganglioside interactions in real time, where MAG, GD1a, and GT1b contents are controlled and they are in their in vivo orientation within fluid lipid bilayers. Using a quartz crystal microbalance with dissipation monitoring (QCM-D) biosensor functionalized with a supported lipid bilayer (SLB) and MAG, we detect vesicular GD1a and GT1b binding and determine the interaction kinetics as a function of vesicular ganglioside content. MAG-bound vesicles are deformed similarly, regardless of the ganglioside or its mole fraction. We further demonstrate how MAG-ganglioside interactions can be disrupted by antiganglioside antibodies that override MAG-based neuron growth inhibition.
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Affiliation(s)
- Jennie L Cawley
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Luke R Jordan
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Nathan J Wittenberg
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
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12
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Cawley J, Wittenberg NJ. An Axon-Myelin Interface Model to Examine Multivalent Interactions between Gangliosides and Myelin-Associated Glycoprotein. Biophys J 2020. [DOI: 10.1016/j.bpj.2019.11.1428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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13
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Blauch ME, Nice JB, Brown AC, Wittenberg NJ. Characterization and Analysis of Leukotoxin-containing Outer Membrane Vesicles. Biophys J 2020. [DOI: 10.1016/j.bpj.2019.11.1775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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14
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Pisapati AV, Wang Y, Blauch ME, Wittenberg NJ, Cheng X, Zhang XF. Characterizing Single-Molecule Conformational Changes Under Shear Flow with Fluorescence Microscopy. J Vis Exp 2020:10.3791/60784. [PMID: 32065139 PMCID: PMC7205595 DOI: 10.3791/60784] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Single-molecule behavior under mechanical perturbation has been characterized widely to understand many biological processes. However, methods such as atomic force microscopy have limited temporal resolution, while Förster resonance energy transfer (FRET) only allow conformations to be inferred. Fluorescence microscopy, on the other hand, allows real-time in situ visualization of single molecules in various flow conditions. Our protocol describes the steps to capture conformational changes of single biomolecules under different shear flow environments using fluorescence microscopy. The shear flow is created inside microfluidic channels and controlled by a syringe pump. As demonstrations of the method, von Willebrand factor (VWF) and lambda DNA are labeled with biotin and fluorophore and then immobilized on the channel surface. Their conformations are continuously monitored under variable shear flow using total internal reflection (TIRF) and confocal fluorescence microscopy. The reversible unraveling dynamics of VWF are useful for understanding how its function is regulated in human blood, while the conformation of lambda DNA offers insights into the biophysics of macromolecules. The protocol can also be widely applied to study the behavior of polymers, especially biopolymers, in varying flow conditions and to investigate the rheology of complex fluids.
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Affiliation(s)
| | - Yi Wang
- Department of Materials Science and Engineering, Lehigh University
| | | | | | - Xuanhong Cheng
- Department of Bioengineering, Lehigh University; Department of Materials Science and Engineering, Lehigh University;
| | - X Frank Zhang
- Department of Bioengineering, Lehigh University; Department of Mechanical Engineering and Mechanics, Lehigh University;
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15
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Abstract
Refractometric sensors utilizing surface plasmon resonance (SPR) should satisfy a series of performance metrics, bulk sensitivity, thin-film sensitivity, refractive-index resolution, and high-Q-factor resonance, as well as practical requirements such as manufacturability and the ability to separate optical and fluidic paths via reflection-mode sensing. While many geometries such as nanohole, nanoslit, and nanoparticles have been employed, it is nontrivial to engineer nanostructures to satisfy all of the aforementioned requirements. We combine gold nanohole arrays with a water-index-matched Cytop film to demonstrate reflection-mode, high-Q-factor (Qexp = 143) symmetric plasmonic sensor architecture. Using template stripping with a Cytop film, we can replicate a large number of index-symmetric nanohole arrays, which support sharp plasmonic resonances that can be probed by light reflected from their backside with a high extinction amplitude. The reflection geometry separates the optical and microfluidic paths without sacrificing sensor performance as is the case of standard (index-asymmetric) nanohole arrays. Furthermore, plasmon hybridization caused by the array refractive-index symmetry enables dual-mode detection that allows distinction of refractive-index changes occurring at different distances from the surface, making it possible to identify SPR response from differently sized particles or to distinguish binding events near the surface from bulk index changes. Due to the unique combination of a dual-mode reflection-configuration sensing, high-Q plasmonic modes, and template-stripping nanofabrication, this platform can extend the utility of nanohole SPR for sensing applications involving biomolecules, polymers, nanovesicles, and biomembranes.
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Affiliation(s)
- Milan Vala
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
- Institute of Photonics and Electronics, Czech Academy of Sciences, 18251 Prague, Czech Republic
| | - Christopher T. Ertsgaard
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Nathan J. Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
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16
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Jordan LR, Blauch ME, Baxter AM, Cawley JL, Wittenberg NJ. Influence of brain gangliosides on the formation and properties of supported lipid bilayers. Colloids Surf B Biointerfaces 2019; 183:110442. [DOI: 10.1016/j.colsurfb.2019.110442] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Revised: 07/30/2019] [Accepted: 08/15/2019] [Indexed: 01/04/2023]
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17
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Ryu YS, Yun H, Chung T, Suh JH, Kim S, Lee K, Wittenberg NJ, Oh SH, Lee B, Lee SD. Kinetics of lipid raft formation at lipid monolayer-bilayer junction probed by surface plasmon resonance. Biosens Bioelectron 2019; 142:111568. [PMID: 31442945 DOI: 10.1016/j.bios.2019.111568] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Revised: 07/27/2019] [Accepted: 08/02/2019] [Indexed: 02/06/2023]
Abstract
A label-free, non-dispruptive, and real-time analytical device to monitor the dynamic features of biomolecules and their interactions with neighboring molecules is an essential prerequisite for biochip- and diagonostic assays. To explore one of the central questions on the lipid-lipid interactions in the course of the liquid-ordered (lo) domain formation, called rafts, we developed a method of reconstituting continuous but spatially heterogeneous lipid membrane platforms with molayer-bilayer juntions (MBJs) that enable to form the lo domains in a spatiotemporally controlled manner. This allows us to detect the time-lapse dynamics of the lipid-lipid interactions during raft formation and resultant membrane phase changes together with the raft-associated receptor-ligand binding through the surface plasmon resonance (SPR). For cross-validation, using epifluorescence microscopy, we demonstrated the underlying mechanisms for raft formations that the infiltration of cholesterols into the sphingolipid-enriched domains plays a crucial roles in the membrane phase-separation. Our membrane platform, being capable of monitoring dynamic interactions among lipids and performing the systematic optical analysis, will unveil physiological roles of cholesterols in a variety of biological events.
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Affiliation(s)
- Yong-Sang Ryu
- School of Electrical and Computer Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea; Sensor System Research Center, Korea Institute of Science and Technology, Seongbuk-gu, Seoul, 02792, South Korea
| | - Hansik Yun
- School of Electrical and Computer Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Taerin Chung
- Inter-University Semiconductor Research Center, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Jeng-Hun Suh
- School of Electrical and Computer Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Sungho Kim
- School of Electrical and Computer Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Kyookeun Lee
- Inter-University Semiconductor Research Center, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Nathan J Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, 200 Union St SE, Minneapolis, MN, 55455, USA; Department of Chemistry, Lehigh University, Bethlehem, PA, 18015, USA
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, 200 Union St SE, Minneapolis, MN, 55455, USA
| | - Byoungho Lee
- School of Electrical and Computer Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Sin-Doo Lee
- School of Electrical and Computer Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea; Inter-University Semiconductor Research Center, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
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18
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Baxter AM, Wittenberg NJ. Excitation of Fluorescent Lipid Probes Accelerates Supported Lipid Bilayer Formation via Photosensitized Lipid Oxidation. Langmuir 2019; 35:11542-11549. [PMID: 31411482 DOI: 10.1021/acs.langmuir.9b01535] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Fluorescent lipid probes are commonly used to label membranes of cells and model membranes like giant vesicles, liposomes, and supported lipid bilayers (SLB). Here, we show that excitation of fluorescent lipid probes with BODIPY-like conjugates results in a significant acceleration of the rupture and SLB formation process for unsaturated phospholipid vesicles on SiO2 surfaces. The resulting SLBs also have smaller measured masses, which is indicative of a reduction in membrane thickness and/or membrane density. The excitation of fluorescent probes with NBD and Texas Red conjugates does not accelerate the SLB formation process. In the absence of fluorescent probes or light, the inclusion of oxidized phospholipids also accelerates SLB formation. The excitation-induced acceleration caused by BODIPY-like probes is eliminated when the probes are present with saturated phospholipids not susceptible to oxidation, and it is attenuated when a lipophilic antioxidant (α-tocopherol) is present. These results suggest that BODIPY-phospholipid conjugates are photosensitizers, and their excitation causes oxidation of lipid membranes, which significantly alters membrane properties.
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Affiliation(s)
- Ashley M Baxter
- Department of Chemistry , Lehigh University , Bethlehem , Pennsylvania 18015 , United States
| | - Nathan J Wittenberg
- Department of Chemistry , Lehigh University , Bethlehem , Pennsylvania 18015 , United States
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19
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Baxter AM, Wittenberg NJ. Excitation of Fluorescent Lipid Probes Accelerates Phospholipid Vesicle Rupture and Supported Lipid Bilayer Formation. Biophys J 2019. [DOI: 10.1016/j.bpj.2018.11.484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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20
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Vala M, Jordan LR, Warrington AE, Maher LJ, Rodriguez M, Wittenberg NJ, Oh SH. Surface Plasmon Resonance Sensing on Naturally Derived Membranes: A Remyelination-Promoting Human Antibody Binds Myelin with Extraordinary Affinity. Anal Chem 2018; 90:12567-12573. [DOI: 10.1021/acs.analchem.8b02664] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Milan Vala
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Luke R. Jordan
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Arthur E. Warrington
- Departments of Neurology and Immunology, Mayo Clinic, Rochester, Minnesota 55905, United States
| | - L. James Maher
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota 55905, United States
| | - Moses Rodriguez
- Departments of Neurology and Immunology, Mayo Clinic, Rochester, Minnesota 55905, United States
| | - Nathan J. Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
- Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
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21
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Ertsgaard CT, Wittenberg NJ, Klemme DJ, Barik A, Shih WC, Oh SH. Integrated Nanogap Platform for Sub-Volt Dielectrophoretic Trapping and Real-Time Raman Imaging of Biological Nanoparticles. Nano Lett 2018; 18:5946-5953. [PMID: 30071732 DOI: 10.1021/acs.nanolett.8b02654] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
A rapid, label-free, and broadly applicable chemical analysis platform for nanovesicles and subcellular components is highly desirable for diagnostic assays. We demonstrate an integrated nanogap plasmonic sensing platform that combines subvolt dielectrophoresis (DEP) trapping, gold nanoparticles (AuNPs), and a lineated illumination scheme for real-time, surface-enhanced Raman spectroscopy (SERS) imaging of biological nanoparticles. Our system is capable of isolating suspended sub-100 nm vesicles and imaging the Raman spectra of their cargo within seconds, 100 times faster than conventional point-scan Raman systems. Bare AuNPs are spiked into solution and simultaneously trapped with the nanovesicles along the gap to boost local optical fields. In addition, our platform offers simultaneous and delay-free spatial and temporal multiplexing functionality. These nanogap devices can be mass-produced via atomic layer lithography and provide a practical platform for high-speed SERS analysis of biological nanoparticles.
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Affiliation(s)
| | - Nathan J Wittenberg
- Department of Chemistry , Lehigh University , Bethlehem , Pennsylvania 18015 , United States
| | | | | | - Wei-Chuan Shih
- Department of Electrical and Computer Engineering , University of Houston , Houston , Texas 77204 , United States
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22
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Rodrigo D, Tittl A, Ait-Bouziad N, John-Herpin A, Limaj O, Kelly C, Yoo D, Wittenberg NJ, Oh SH, Lashuel HA, Altug H. Resolving molecule-specific information in dynamic lipid membrane processes with multi-resonant infrared metasurfaces. Nat Commun 2018; 9:2160. [PMID: 29867181 PMCID: PMC5986821 DOI: 10.1038/s41467-018-04594-x] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 05/04/2018] [Indexed: 12/12/2022] Open
Abstract
A multitude of biological processes are enabled by complex interactions between lipid membranes and proteins. To understand such dynamic processes, it is crucial to differentiate the constituent biomolecular species and track their individual time evolution without invasive labels. Here, we present a label-free mid-infrared biosensor capable of distinguishing multiple analytes in heterogeneous biological samples with high sensitivity. Our technology leverages a multi-resonant metasurface to simultaneously enhance the different vibrational fingerprints of multiple biomolecules. By providing up to 1000-fold near-field intensity enhancement over both amide and methylene bands, our sensor resolves the interactions of lipid membranes with different polypeptides in real time. Significantly, we demonstrate that our label-free chemically specific sensor can analyze peptide-induced neurotransmitter cargo release from synaptic vesicle mimics. Our sensor opens up exciting possibilities for gaining new insights into biological processes such as signaling or transport in basic research as well as provides a valuable toolkit for bioanalytical and pharmaceutical applications.
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Affiliation(s)
- Daniel Rodrigo
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
- ICFO - Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, 08860, Castelldefels, Spain
| | - Andreas Tittl
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Nadine Ait-Bouziad
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Aurelian John-Herpin
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Odeta Limaj
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Christopher Kelly
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
- School of Chemistry, University of Glasgow, Joseph Black Building, Glasgow, G12 8QQ, UK
| | - Daehan Yoo
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Nathan J Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN, 55455, USA
- Department of Chemistry, Lehigh University, Bethlehem, PA, 18015, USA
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN, 55455, USA
| | - Hilal A Lashuel
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Hatice Altug
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.
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23
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Lin C, Stedronsky ER, Jordan LR, Wittenberg NJ, Regen SL. A plug and socket approach for tightening polyelectrolyte multilayers. Chem Commun (Camb) 2018; 54:9769-9772. [DOI: 10.1039/c8cc04550j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A plug and socket approach for tightening polyelectrolyte multilayers is introduced based on the use pendant β-cyclodextrin groups.
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Affiliation(s)
- Cen Lin
- Department of Chemistry
- Lehigh University
- Bethlehem
- USA
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24
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Ryu YS, Wittenberg NJ, Suh JH, Lee SW, Sohn Y, Oh SH, Parikh AN, Lee SD. Continuity of Monolayer-Bilayer Junctions for Localization of Lipid Raft Microdomains in Model Membranes. Sci Rep 2016; 6:26823. [PMID: 27230411 PMCID: PMC4882513 DOI: 10.1038/srep26823] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 05/09/2016] [Indexed: 11/16/2022] Open
Abstract
We show that the selective localization of cholesterol-rich domains and associated ganglioside receptors prefer to occur in the monolayer across continuous monolayer-bilayer junctions (MBJs) in supported lipid membranes. For the MBJs, glass substrates were patterned with poly(dimethylsiloxane) (PDMS) oligomers by thermally-assisted contact printing, leaving behind 3 nm-thick PDMS patterns. The hydrophobicity of the transferred PDMS patterns was precisely tuned by the stamping temperature. Lipid monolayers were formed on the PDMS patterned surface while lipid bilayers were on the bare glass surface. Due to the continuity of the lipid membranes over the MBJs, essentially free diffusion of lipids was allowed between the monolayer on the PDMS surface and the upper leaflet of the bilayer on the glass substrate. The preferential localization of sphingomyelin, ganglioside GM1 and cholesterol in the monolayer region enabled to develop raft microdomains through coarsening of nanorafts. Our methodology provides a simple and effective scheme of non-disruptive manipulation of the chemical landscape associated with lipid phase separations, which leads to more sophisticated applications in biosensors and as cell culture substrates.
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Affiliation(s)
- Yong-Sang Ryu
- School of Electrical Engineering #032, Seoul National University, Kwanak P.O. Box 34, Seoul 151-600 Korea
| | - Nathan J. Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Jeng-Hun Suh
- School of Electrical Engineering #032, Seoul National University, Kwanak P.O. Box 34, Seoul 151-600 Korea
| | - Sang-Wook Lee
- School of Electrical Engineering #032, Seoul National University, Kwanak P.O. Box 34, Seoul 151-600 Korea
| | - Youngjoo Sohn
- Department of Anatomy, College of Korean Medicine, Institute of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Atul N. Parikh
- Departments of Biomedical Engineering and Chemical Engineering & Materials Science, University of California, Davis, California 95616, USA
| | - Sin-Doo Lee
- School of Electrical Engineering #032, Seoul National University, Kwanak P.O. Box 34, Seoul 151-600 Korea
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25
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Wootla B, Watzlawik JO, Warrington AE, Wittenberg NJ, Denic A, Xu X, Jordan LR, Papke LM, Zoecklein LJ, Pierce ML, Oh SH, Kantarci OH, Rodriguez M. Naturally Occurring Monoclonal Antibodies and Their Therapeutic Potential for Neurologic Diseases. JAMA Neurol 2016; 72:1346-53. [PMID: 26389734 DOI: 10.1001/jamaneurol.2015.2188] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
IMPORTANCE Modulating the immune system does not reverse long-term disability in neurologic disorders. Better neuroregenerative and neuroprotective treatment strategies are needed for neuroinflammatory and neurodegenerative diseases. OBJECTIVE To review the role of monoclonal, naturally occurring antibodies (NAbs) as novel therapeutic molecules for treatment of neurologic disorders. EVIDENCE REVIEW Peer-reviewed articles, including case reports, case series, retrospective reviews, prospective randomized clinical trials, and basic science reports, were identified in a PubMed search for articles about NAbs and neurologic disorders that were published from January 1, 1964, through June 30, 2015. We concentrated our review on multiple sclerosis, Parkinson disease, Alzheimer disease, and amyotrophic lateral sclerosis. FINDINGS Many insults, including trauma, ischemia, infection, inflammation, and neurodegeneration, result in irreversible damage to the central nervous system. Central nervous system injury often results in a pervasive inhibitory microenvironment that hinders regeneration. A common targeted drug development strategy is to identify molecules with high potency in animal models. Many approaches often fail in the clinical setting owing to a lack of efficacy in human diseases (eg, less than the response demonstrated in animal models) or a high incidence of toxic effects. An alternative approach is to identify NAbs in humans because these therapeutic molecules have potential physiologic function without toxic effects. NAbs of the IgG, IgA, or IgM isotype contain germline or close to germline sequences and are reactive to self-components, altered self-components, or foreign antigens. Our investigative group developed recombinant, autoreactive, natural human IgM antibodies directed against oligodendrocytes or neurons with therapeutic potential for central nervous system repair. One such molecule, recombinant HIgM22, directed against myelin and oligodendrocytes completed a successful phase 1 clinical trial without toxic effects with the goal of promoting remyelination in multiple sclerosis. CONCLUSIONS AND RELEVANCE Animal studies demonstrate that certain monoclonal NAbs are beneficial as therapeutic agents for neurologic diseases. This class of antibodies represents a unique source from which to develop a new class of disease-modifying therapies.
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Affiliation(s)
- Bharath Wootla
- Department of Neurology, Mayo Clinic, Rochester, Minnesota2Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, Minnesota
| | - Jens O Watzlawik
- Department of Neurology, Mayo Clinic, Rochester, Minnesota2Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, Minnesota
| | - Arthur E Warrington
- Department of Neurology, Mayo Clinic, Rochester, Minnesota2Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, Minnesota
| | - Nathan J Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis4Department of Biomedical Engineering, University of Minnesota, Minneapolis
| | - Aleksandar Denic
- Department of Neurology, Mayo Clinic, Rochester, Minnesota2Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, Minnesota
| | - Xiaohua Xu
- Department of Neurology, Mayo Clinic, Rochester, Minnesota2Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, Minnesota
| | - Luke R Jordan
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis4Department of Biomedical Engineering, University of Minnesota, Minneapolis
| | - Louisa M Papke
- Department of Neurology, Mayo Clinic, Rochester, Minnesota2Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, Minnesota
| | - Laurie J Zoecklein
- Department of Neurology, Mayo Clinic, Rochester, Minnesota2Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, Minnesota
| | - Mabel L Pierce
- Department of Neurology, Mayo Clinic, Rochester, Minnesota2Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, Minnesota
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis4Department of Biomedical Engineering, University of Minnesota, Minneapolis
| | - Orhun H Kantarci
- Department of Neurology, Mayo Clinic, Rochester, Minnesota2Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, Minnesota
| | - Moses Rodriguez
- Department of Neurology, Mayo Clinic, Rochester, Minnesota2Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, Minnesota5Department of Immunology, Mayo Clinic, Rochester, Minnesota
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26
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Wootla B, Watzlawik JO, Stavropoulos N, Wittenberg NJ, Dasari H, Abdelrahim MA, Henley JR, Oh SH, Warrington AE, Rodriguez M. Recent Advances in Monoclonal Antibody Therapies for Multiple Sclerosis. Expert Opin Biol Ther 2016; 16:827-839. [PMID: 26914737 DOI: 10.1517/14712598.2016.1158809] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Multiple sclerosis (MS) is the most common chronic inflammatory, demyelinating disease of the CNS and results in neurological disability. Existing immunomodulatory and immunosuppressive approaches lower the number of relapses but do not cure or reverse existing deficits nor improve long-term disability in MS patients. AREAS COVERED Monogenic antibodies were described as treatment options for MS, however the immunogenicity of mouse antibodies hampered the efficacy of potential therapeutics in humans. Availability of improved antibody production technologies resulted in a paradigm shift in MS treatment strategies. In this review, an overview of immunotherapies for MS that use conventional monoclonal antibodies reactive to immune system and their properties and mechanisms of action will be discussed, including recent advances in MS therapeutics and highlight natural autoantibodies (NAbs) that directly target CNS cells. EXPERT OPINION Recent challenges for MS therapy are the identification of relevant molecular and cellular targets, time frame of treatment, and antibody toxicity profiles to identify safe treatment options for MS patients. The application of monoclonal antibody therapies with better biological efficacy associated with minimum side effects possesses huge clinical potential. Advances in monoclonal antibody technologies that directly target cells of nervous system may promote the CNS regeneration field from bench to bedside.
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Affiliation(s)
- Bharath Wootla
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.,Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.,Department of Physiology and Biomedical Engineering, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Jens O Watzlawik
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road S, Jacksonville, FL 32224, USA
| | - Nikolaos Stavropoulos
- Department of General Medicine, Charles University in Prague, Faculty of Medicine in Hradec Kralove, Simkova 870, Hradec Kralove 1, 500 38, Czech Republic
| | - Nathan J Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, 200 Union Street SE, 4-174 Keller Hall Minneapolis, MN 55455, USA.,Department of Biomedical Engineering, University of Minnesota, 200 Union Street SE, 4-174 Keller Hall Minneapolis, MN 55455, USA
| | - Harika Dasari
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.,Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Murtada A Abdelrahim
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.,Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - John R Henley
- Department of Neurologic Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.,Department of Physiology and Biomedical Engineering, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.,Center for Regenerative Medicine, Neuroregeneration, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, 200 Union Street SE, 4-174 Keller Hall Minneapolis, MN 55455, USA.,Department of Biomedical Engineering, University of Minnesota, 200 Union Street SE, 4-174 Keller Hall Minneapolis, MN 55455, USA
| | - Arthur E Warrington
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.,Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
| | - Moses Rodriguez
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.,Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.,Department of Immunology, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA
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27
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Jackman JA, Linardy E, Yoo D, Seo J, Ng WB, Klemme DJ, Wittenberg NJ, Oh SH, Cho NJ. Plasmonic Nanohole Sensor for Capturing Single Virus-Like Particles toward Virucidal Drug Evaluation. Small 2016; 12:1159-66. [PMID: 26450658 DOI: 10.1002/smll.201501914] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 08/25/2015] [Indexed: 05/18/2023]
Abstract
A plasmonic nanohole sensor for virus-like particle capture and virucidal drug evaluation is reported. Using a materials-selective surface functionalization scheme, passive immobilization of virus-like particles only within the nanoholes is achieved. The findings demonstrate that a low surface coverage of particles only inside the functionalized nanoholes significantly improves nanoplasmonic sensing performance over conventional nanohole arrays.
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Affiliation(s)
- Joshua A Jackman
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
- Centre for Biomimetic Sensor Science, Nanyang Technological University, 50 Nanyang Drive, 637553, Singapore
| | - Eric Linardy
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
- Centre for Biomimetic Sensor Science, Nanyang Technological University, 50 Nanyang Drive, 637553, Singapore
| | - Daehan Yoo
- Department of Electrical and Computer Engineering, University of Minnesota, 200 Union Street SE, Minneapolis, MN, 55455, USA
| | - Jeongeun Seo
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
- Centre for Biomimetic Sensor Science, Nanyang Technological University, 50 Nanyang Drive, 637553, Singapore
| | - Wei Beng Ng
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
- Centre for Biomimetic Sensor Science, Nanyang Technological University, 50 Nanyang Drive, 637553, Singapore
| | - Daniel J Klemme
- Department of Electrical and Computer Engineering, University of Minnesota, 200 Union Street SE, Minneapolis, MN, 55455, USA
| | - Nathan J Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, 200 Union Street SE, Minneapolis, MN, 55455, USA
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, 200 Union Street SE, Minneapolis, MN, 55455, USA
| | - Nam-Joon Cho
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
- Centre for Biomimetic Sensor Science, Nanyang Technological University, 50 Nanyang Drive, 637553, Singapore
- School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459, Singapore
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28
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Limaj O, Etezadi D, Wittenberg NJ, Rodrigo D, Yoo D, Oh SH, Altug H. Infrared Plasmonic Biosensor for Real-Time and Label-Free Monitoring of Lipid Membranes. Nano Lett 2016; 16:1502-8. [PMID: 26761392 DOI: 10.1021/acs.nanolett.5b05316] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
In this work, we present an infrared plasmonic biosensor for chemical-specific detection and monitoring of biomimetic lipid membranes in a label-free and real-time fashion. Lipid membranes constitute the primary biological interface mediating cell signaling and interaction with drugs and pathogens. By exploiting the plasmonic field enhancement in the vicinity of engineered and surface-modified nanoantennas, the proposed biosensor is able to capture the vibrational fingerprints of lipid molecules and monitor in real time the formation kinetics of planar biomimetic membranes in aqueous environments. Furthermore, we show that this plasmonic biosensor features high-field enhancement extending over tens of nanometers away from the surface, matching the size of typical bioassays while preserving high sensitivity.
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Affiliation(s)
- Odeta Limaj
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL) , Lausanne 1015, Switzerland
| | - Dordaneh Etezadi
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL) , Lausanne 1015, Switzerland
| | - Nathan J Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Daniel Rodrigo
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL) , Lausanne 1015, Switzerland
| | - Daehan Yoo
- Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Hatice Altug
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne (EPFL) , Lausanne 1015, Switzerland
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29
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Barik A, Cherukulappurath S, Wittenberg NJ, Johnson TW, Oh SH. Dielectrophoresis-Assisted Raman Spectroscopy of Intravesicular Analytes on Metallic Pyramids. Anal Chem 2016; 88:1704-10. [DOI: 10.1021/acs.analchem.5b03719] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Avijit Barik
- Department of Electrical
and Computer Engineering, ‡Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Sudhir Cherukulappurath
- Department of Electrical
and Computer Engineering, ‡Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Nathan J. Wittenberg
- Department of Electrical
and Computer Engineering, ‡Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Timothy W. Johnson
- Department of Electrical
and Computer Engineering, ‡Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Sang-Hyun Oh
- Department of Electrical
and Computer Engineering, ‡Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
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30
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Abstract
We present periodic nanohole arrays fabricated in free-standing metal-coated nitride films as a platform for trapping and analyzing single organelles. When a microliter-scale droplet containing mitochondria is dispensed above the nanohole array, the combination of evaporation and capillary flow directs individual mitochondria to the nanoholes. Mammalian mitochondria arrays were rapidly formed on chip using this technique without any surface modification steps, microfluidic interconnects, or external power sources. The trapped mitochondria were depolarized on chip using an ionophore with results showing that the organelle viability and behavior were preserved during the on-chip assembly process. Fluorescence signal related to mitochondrial membrane potential was obtained from single mitochondria trapped in individual nanoholes revealing statistical differences between the behavior of polarized vs depolarized mammalian mitochondria. This technique provides a fast and stable route for droplet-based directed localization of organelles-on-a-chip with minimal limitations and complexity, as well as promotes integration with other optical or electrochemical detection techniques.
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Affiliation(s)
- Shailabh Kumar
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, United States
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, United States
| | - Gregory G. Wolken
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, United States
| | - Nathan J. Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, United States
| | - Edgar A. Arriaga
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, United States
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, United States
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, United States
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, United States
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31
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Ryu YS, Yoo D, Wittenberg NJ, Jordan LR, Lee SD, Parikh AN, Oh SH. Lipid Membrane Deformation Accompanied by Disk-to-Ring Shape Transition of Cholesterol-Rich Domains. J Am Chem Soc 2015; 137:8692-5. [PMID: 26053547 DOI: 10.1021/jacs.5b04559] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
During vesicle budding or endocytosis, biomembranes undergo a series of lipid- and protein-mediated deformations involving cholesterol-enriched lipid rafts. If lipid rafts of high bending rigidities become confined to the incipient curved membrane topology such as a bud-neck interface, they can be expected to reform as ring-shaped rafts. Here, we report on the observation of a disk-to-ring shape morpho-chemical transition of a model membrane in the absence of geometric constraints. The raft shape transition is triggered by lateral compositional heterogeneity and is accompanied by membrane deformation in the vertical direction, which is detected by height-sensitive fluorescence interference contrast microscopy. Our results suggest that a flat membrane can become curved simply by dynamic changes in local chemical composition and shape transformation of cholesterol-rich domains.
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Affiliation(s)
| | | | | | | | - Sin-Doo Lee
- §School of Electrical Engineering, Seoul National University, Seoul, Republic of Korea 151-742
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32
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Xu X, Denic A, Jordan LR, Wittenberg NJ, Warrington AE, Wootla B, Papke LM, Zoecklein LJ, Yoo D, Shaver J, Oh SH, Pease LR, Rodriguez M. A natural human IgM that binds to gangliosides is therapeutic in murine models of amyotrophic lateral sclerosis. Dis Model Mech 2015; 8:831-42. [PMID: 26035393 PMCID: PMC4527295 DOI: 10.1242/dmm.020727] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 05/18/2015] [Indexed: 12/21/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a devastating, fatal neurological disease that primarily affects spinal cord anterior horn cells and their axons for which there is no treatment. Here we report the use of a recombinant natural human IgM that binds to the surface of neurons and supports neurite extension, rHIgM12, as a therapeutic strategy in murine models of human ALS. A single 200 µg intraperitoneal dose of rHIgM12 increases survival in two independent genetic-based mutant SOD1 mouse strains (SOD1G86R and SOD1G93A) by 8 and 10 days, delays the onset of neurological deficits by 16 days, delays the onset of weight loss by 5 days, and preserves spinal cord axons and anterior horn neurons. Immuno-overlay of thin layer chromatography and surface plasmon resonance show that rHIgM12 binds with high affinity to the complex gangliosides GD1a and GT1b. Addition of rHIgM12 to neurons in culture increases α-tubulin tyrosination levels, suggesting an alteration of microtubule dynamics. We previously reported that a single peripheral dose of rHIgM12 preserved neurological function in a murine model of demyelination with axon loss. Because rHIgM12 improves three different models of neurological disease, we propose that the IgM might act late in the cascade of neuronal stress and/or death by a broad mechanism. Summary: A single peripheral dose of a recombinant natural human IgM increases lifespan and delays neurological deficits in mouse models of human ALS.
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Affiliation(s)
- Xiaohua Xu
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
| | | | - Luke R Jordan
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Nathan J Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | | | - Bharath Wootla
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
| | - Louisa M Papke
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
| | | | - Daehan Yoo
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Jonah Shaver
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Larry R Pease
- Department of Immunology, Mayo Clinic, Rochester, MN 55905, USA
| | - Moses Rodriguez
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
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33
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Ryu YS, Lee IH, Suh JH, Park SC, Oh S, Jordan LR, Wittenberg NJ, Oh SH, Jeon NL, Lee B, Parikh AN, Lee SD. Reconstituting ring-rafts in bud-mimicking topography of model membranes. Nat Commun 2014; 5:4507. [PMID: 25058275 PMCID: PMC4124864 DOI: 10.1038/ncomms5507] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 06/25/2014] [Indexed: 01/30/2023] Open
Abstract
During vesicular trafficking and release of enveloped viruses, the budding and fission processes dynamically remodel the donor cell membrane in a protein- or a lipid-mediated manner. In all cases, in addition to the generation or relief of the curvature stress, the buds recruit specific lipids and proteins from the donor membrane through restricted diffusion for the development of a ring-type raft domain of closed topology. Here, by reconstituting the bud topography in a model membrane, we demonstrate the preferential localization of cholesterol- and sphingomyelin-enriched microdomains in the collar band of the bud-neck interfaced with the donor membrane. The geometrical approach to the recapitulation of the dynamic membrane reorganization, resulting from the local radii of curvatures from nanometre-to-micrometre scales, offers important clues for understanding the active roles of the bud topography in the sorting and migration machinery of key signalling proteins involved in membrane budding.
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Affiliation(s)
- Yong-Sang Ryu
- School of Electrical Engineering #032, Seoul National University, Kwanak P.O. Box 34, Seoul 151-600, Republic of Korea
| | - In-Ho Lee
- School of Electrical Engineering #032, Seoul National University, Kwanak P.O. Box 34, Seoul 151-600, Republic of Korea
| | - Jeng-Hun Suh
- School of Electrical Engineering #032, Seoul National University, Kwanak P.O. Box 34, Seoul 151-600, Republic of Korea
| | - Seung Chul Park
- School of Electrical Engineering #032, Seoul National University, Kwanak P.O. Box 34, Seoul 151-600, Republic of Korea
| | - Soojung Oh
- World Class University (WCU) Program of Multiscale Mechanical Design, School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-744, Republic of Korea
| | - Luke R. Jordan
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Nathan J. Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Sang-Hyun Oh
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Noo Li Jeon
- World Class University (WCU) Program of Multiscale Mechanical Design, School of Mechanical and Aerospace Engineering, Seoul National University, Seoul 151-744, Republic of Korea
| | - Byoungho Lee
- School of Electrical Engineering #032, Seoul National University, Kwanak P.O. Box 34, Seoul 151-600, Republic of Korea
| | - Atul N. Parikh
- Department of Biomedical Engineering and Chemical Engineering and Materials Science, University of California, Davis, California 95616, USA
- Centre for Biomimetic Sensor Science, School of Materials Science and Engineering, Nanyang Technological University, Singapore 637553, Singapore
| | - Sin-Doo Lee
- School of Electrical Engineering #032, Seoul National University, Kwanak P.O. Box 34, Seoul 151-600, Republic of Korea
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34
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Wittenberg NJ, Johnson TW, Jordan LR, Xu X, Warrington AE, Rodriguez M, Oh SH. Formation of biomembrane microarrays with a squeegee-based assembly method. J Vis Exp 2014:51501. [PMID: 24837169 PMCID: PMC4032179 DOI: 10.3791/51501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Lipid bilayer membranes form the plasma membranes of cells and define the boundaries of subcellular organelles. In nature, these membranes are heterogeneous mixtures of many types of lipids, contain membrane-bound proteins and are decorated with carbohydrates. In some experiments, it is desirable to decouple the biophysical or biochemical properties of the lipid bilayer from those of the natural membrane. Such cases call for the use of model systems such as giant vesicles, liposomes or supported lipid bilayers (SLBs). Arrays of SLBs are particularly attractive for sensing applications and mimicking cell-cell interactions. Here we describe a new method for forming SLB arrays. Submicron-diameter SiO2 beads are first coated with lipid bilayers to form spherical SLBs (SSLBs). The beads are then deposited into an array of micro-fabricated submicron-diameter microwells. The preparation technique uses a "squeegee" to clean the substrate surface, while leaving behind SSLBs that have settled into microwells. This method requires no chemical modification of the microwell substrate, nor any particular targeting ligands on the SSLB. Microwells are occupied by single beads because the well diameter is tuned to be just larger than the bead diameter. Typically, more 75% of the wells are occupied, while the rest remain empty. In buffer SSLB arrays display long-term stability of greater than one week. Multiple types of SSLBs can be placed in a single array by serial deposition, and the arrays can be used for sensing, which we demonstrate by characterizing the interaction of cholera toxin with ganglioside GM1. We also show that phospholipid vesicles without the bead supports and biomembranes from cellular sources can be arrayed with the same method and cell-specific membrane lipids can be identified.
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Affiliation(s)
| | - Timothy W Johnson
- Department of Electrical and Computer Engineering, University of Minnesota
| | - Luke R Jordan
- Department of Biomedical Engineering, University of Minnesota
| | - Xiaohua Xu
- Department of Neurology, Mayo Clinic College of Medicine
| | | | - Moses Rodriguez
- Department of Neurology, Mayo Clinic College of Medicine; Department of Immunology, Mayo Clinic College of Medicine
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota; Department of Biomedical Engineering, University of Minnesota
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35
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Wittenberg NJ, Wootla B, Jordan LR, Denic A, Warrington AE, Oh SH, Rodriguez M. Applications of SPR for the characterization of molecules important in the pathogenesis and treatment of neurodegenerative diseases. Expert Rev Neurother 2014; 14:449-63. [PMID: 24625008 PMCID: PMC3989105 DOI: 10.1586/14737175.2014.896199] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Characterization of binding kinetics and affinity between a potential drug and its receptor are key steps in the development of new drugs. Among the techniques available to determine binding affinities, surface plasmon resonance has emerged as the gold standard because it can measure binding and dissociation rates in real-time in a label-free fashion. Surface plasmon resonance is now finding applications in the characterization of molecules for treatment of neurodegenerative diseases, characterization of molecules associated with pathogenesis of neurodegenerative diseases and detection of neurodegenerative disease biomarkers. In addition it has been used in the characterization of a new class of natural autoantibodies that have therapeutic potential in a number of neurologic diseases. In this review we will introduce surface plasmon resonance and describe some applications of the technique that pertain to neurodegenerative disorders and their treatment.
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Affiliation(s)
- Nathan J. Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN USA
| | - Bharath Wootla
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, MN USA
| | - Luke R. Jordan
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN USA
| | - Aleksandar Denic
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, MN USA
| | | | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN USA
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN USA
| | - Moses Rodriguez
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN USA
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN USA
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36
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Abstract
Optical biosensors based on surface plasmon resonance (SPR) in metallic thin films are currently standard tools for measuring molecular binding kinetics and affinities - an important task for biophysical studies and pharmaceutical development. Motivated by recent progress in the design and fabrication of metallic nanostructures, such as nanoparticles or nanoholes of various shapes, researchers have been pursuing a new generation of biosensors harnessing tailored plasmonic effects in these engineered nanostructures. Nanoplasmonic devices, while demanding nanofabrication, offer tunability with respect to sensor dimension and physical properties, thereby enabling novel biological interfacing opportunities and extreme miniaturization. Here we provide an integrated overview of refractometric biosensing with nanoplasmonic devices and highlight some recent examples of nanoplasmonic sensors capable of unique functions that are difficult to accomplish with conventional SPR. For example, since the local field strength and spatial distribution can be readily tuned by varying the shape and arrangement of nanostructures, biomolecular interactions can be controlled to occur in regions of high field strength. This may improve signal-to-noise and also enable sensing a small number of molecules. Furthermore, the nanoscale plasmonic sensor elements may, in combination with nanofabrication and materials-selective surface-modifications, make it possible to merge affinity biosensing with nanofluidic liquid handling.
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Affiliation(s)
- Andreas B. Dahlin
- Chalmers University of Technology, Division of Bionanophotonics, Department of Applied Physics, Fysikgränd 3, 41296, Göteborg, Sweden
| | - Nathan J. Wittenberg
- Department of Electrical and Computer Engineering, Laboratory of Nanostructures and Biosensing, University of Minnesota, Twin Cities, 200 Union St. S.E., Minneapolis, MN 55455, U.S.A
| | - Fredrik Höök
- Chalmers University of Technology, Division of Bionanophotonics, Department of Applied Physics, Fysikgränd 3, 41296, Göteborg, Sweden
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, Laboratory of Nanostructures and Biosensing, University of Minnesota, Twin Cities, 200 Union St. S.E., Minneapolis, MN 55455, U.S.A
- Department of Biophysics and Chemical Biology, Seoul National University, Seoul 151-747, Korea
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37
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Xu X, Wittenberg NJ, Jordan LR, Kumar S, Watzlawik JO, Warrington AE, Oh SH, Rodriguez M. A patterned recombinant human IgM guides neurite outgrowth of CNS neurons. Sci Rep 2013; 3:2267. [PMID: 23881231 PMCID: PMC3721078 DOI: 10.1038/srep02267] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 06/26/2013] [Indexed: 11/13/2022] Open
Abstract
Matrix molecules convey biochemical and physical guiding signals to neurons in the central nervous system (CNS) and shape the trajectory of neuronal fibers that constitute neural networks. We have developed recombinant human IgMs that bind to epitopes on neural cells, with the aim of treating neurological diseases. Here we test the hypothesis that recombinant human IgMs (rHIgM) can guide neurite outgrowth of CNS neurons. Microcontact printing was employed to pattern rHIgM12 and rHIgM22, antibodies that were bioengineered to have variable regions capable of binding to neurons or oligodendrocytes, respectively. rHIgM12 promoted neuronal attachment and guided outgrowth of neurites from hippocampal neurons. Processes from spinal neurons followed grid patterns of rHIgM12 and formed a physical network. Comparison between rHIgM12 and rHIgM22 suggested the biochemistry that facilitates anchoring the neuronal surfaces is a prerequisite for the function of IgM, and spatial properties cooperate in guiding the assembly of neuronal networks.
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Affiliation(s)
- Xiaohua Xu
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
- These authors contributed equally to this work
| | - Nathan J. Wittenberg
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455 USA
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455 USA
- These authors contributed equally to this work
| | - Luke R. Jordan
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455 USA
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455 USA
| | - Shailabh Kumar
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455 USA
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455 USA
| | - Jens O. Watzlawik
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
| | - Arthur E. Warrington
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
| | - Sang-Hyun Oh
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455 USA
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455 USA
| | - Moses Rodriguez
- Department of Neurology, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
- Department of Immunology, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
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38
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Abstract
Metallic nanopore arrays have emerged as optofluidic platforms with multifarious sensing and analytical capabilities such as label-free surface plasmon resonance (SPR) sensing of molecular binding interactions and surface-enhanced Raman spectroscopy (SERS). However, directed delivery of analytes through open nanopores using traditional methods such as external electric fields or pressure gradients still remains difficult. We demonstrate that nanopore arrays have an intrinsic ability to promote flow through them via capillary flow and evaporation. This passive "nano-drain" mechanism is utilized to concentrate biomolecules on the surface of nanopores for improved detection sensitivity or create ordered nanoscale arrays of beads and liposomes. Without using any external pump or fluidic interconnects, we can concentrate and detect the presence of less than a femtomole of streptavidin in 10 μL of sample using fluorescence imaging. Liposome nanoarrays are also prepared in less than 5 min and used to detect lipid-protein interactions. We also demonstrate label-free SPR detection of analytes using metallic nanopore arrays. This method provides a fast, simple, transportable, and small-volume platform for labeled as well as label-free plasmonic analysis while improving the detection time and sensitivity.
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Affiliation(s)
- Shailabh Kumar
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA
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39
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Lee SH, Lindquist NC, Wittenberg NJ, Jordan LR, Oh SH. Real-time full-spectral imaging and affinity measurements from 50 microfluidic channels using nanohole surface plasmon resonance. Lab Chip 2012; 12:3882-90. [PMID: 22895607 PMCID: PMC3447124 DOI: 10.1039/c2lc40455a] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
With recent advances in high-throughput proteomics and systems biology, there is a growing demand for new instruments that can precisely quantify a wide range of receptor-ligand binding kinetics in a high-throughput fashion. Here we demonstrate a surface plasmon resonance (SPR) imaging spectroscopy instrument capable of simultaneously extracting binding kinetics and affinities from 50 parallel microfluidic channels. The instrument utilizes large-area (~ cm(2)) metallic nanohole arrays as SPR sensing substrates and combines a broadband light source, a high-resolution imaging spectrometer and a low-noise CCD camera to extract spectral information from every channel in real time with a refractive index resolution of 7.7 × 10(-6) refractive index units. To demonstrate the utility of our instrument for quantifying a wide range of biomolecular interactions, each parallel microfluidic channel is coated with a biomimetic supported lipid membrane containing ganglioside (GM1) receptors. The binding kinetics of cholera toxin b (CTX-b) to GM1 are then measured in a single experiment from 50 channels. By combining the highly parallel microfluidic device with large-area periodic nanohole array chips, our SPR imaging spectrometer system enables high-throughput, label-free, real-time SPR biosensing, and its full-spectral imaging capability combined with nanohole arrays could enable integration of SPR imaging with concurrent surface-enhanced Raman spectroscopy.
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Affiliation(s)
- Si Hoon Lee
- Laboratory of Nanostructures and Biosensing, University of Minnesota, Minneapolis, MN 55455, United States
| | | | - Nathan J. Wittenberg
- Laboratory of Nanostructures and Biosensing, University of Minnesota, Minneapolis, MN 55455, United States
| | - Luke R. Jordan
- Laboratory of Nanostructures and Biosensing, University of Minnesota, Minneapolis, MN 55455, United States
| | - Sang-Hyun Oh
- Laboratory of Nanostructures and Biosensing, University of Minnesota, Minneapolis, MN 55455, United States
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40
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Abstract
Lipid bilayer membranes found in nature are heterogeneous mixtures of lipids and proteins. Model systems, such as supported lipid bilayers (SLBs), are often employed to simplify experimental systems while mimicking the properties of natural lipid bilayers. Here, we demonstrate a new method to form SLB arrays by first forming spherical supported lipid bilayers (SSLBs) on submicrometer-diameter SiO(2) beads. The SSLBs are then arrayed into microwells using a simple physical assembly method that requires no chemical modification of the substrate nor modification of the lipid membrane with recognition moieties. The resulting arrays have submicrometer SSLBs with 3 μm periodicity where >75% of the microwells are occupied by an individual SSLB. Because the arrays have high density, fluorescence from >1000 discrete SSLBs can be acquired with a single image capture. We show that 2-component random arrays can be formed, and we also use the arrays to determine the equilibrium dissociation constant for cholera toxin binding to ganglioside GM1. SSLB arrays are robust and are stable for at least one week in buffer.
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Affiliation(s)
- Nathan J. Wittenberg
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Timothy W. Johnson
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Sang-Hyun Oh
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA
- Department of Biophysics and Chemical Biology, Seoul National University, Seoul 151-747, Korea
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41
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Wittenberg NJ, Im H, Xu X, Wootla B, Watzlawik J, Warrington AE, Rodriguez M, Oh SH. High-affinity binding of remyelinating natural autoantibodies to myelin-mimicking lipid bilayers revealed by nanohole surface plasmon resonance. Anal Chem 2012; 84:6031-9. [PMID: 22762372 PMCID: PMC3417152 DOI: 10.1021/ac300819a] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Multiple sclerosis is a progressive neurological disorder that results in the degradation of myelin sheaths that insulate axons in the central nervous system. Therefore promotion of myelin repair is a major thrust of multiple sclerosis treatment research. Two mouse monoclonal natural autoantibodies, O1 and O4, promote myelin repair in several mouse models of multiple sclerosis. Natural autoantibodies are generally polyreactive and predominantly of the IgM isotype. The prevailing paradigm is that because they are polyreactive, these antibodies bind antigens with low affinities. Despite their wide use in neuroscience and glial cell research, however, the affinities and kinetic constants of O1 and O4 antibodies have not been measured to date. In this work, we developed a membrane biosensing platform based on surface plasmon resonance in gold nanohole arrays with a series of surface modification techniques to form myelin-mimicking lipid bilayer membranes to measure both the association and dissociation rate constants for O1 and O4 antibodies binding to their myelin lipid antigens. The ratio of rate constants shows that O1 and O4 bind to galactocerebroside and sulfated galactocerebroside, respectively, with unusually small apparent dissociation constants (K(D) ≈ 0.9 nM) for natural autoantibodies. This is approximately one to 2 orders of magnitude lower than typically observed for the highest affinity natural autoantibodies. We propose that the unusually high affinity of O1 and O4 to their targets in myelin contributes to the mechanism by which they signal oligodendrocytes and induce central nervous system repair.
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Affiliation(s)
- Nathan J. Wittenberg
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455 USA
| | - Hyungsoon Im
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455 USA
| | - Xiaohua Xu
- Departments of Neurology, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
| | - Bharath Wootla
- Departments of Neurology, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
| | - Jens Watzlawik
- Departments of Neurology, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
- Immunology, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
| | - Arthur E. Warrington
- Departments of Neurology, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
| | - Moses Rodriguez
- Departments of Neurology, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
- Immunology, Mayo Clinic College of Medicine, Rochester, MN 55905 USA
| | - Sang-Hyun Oh
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455 USA
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Im H, Wittenberg NJ, Lindquist NC, Oh SH. Atomic layer deposition (ALD): A versatile technique for plasmonics and nanobiotechnology. J Mater Res 2012; 27:663-671. [PMID: 22865951 PMCID: PMC3410655 DOI: 10.1557/jmr.2011.434] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
While atomic layer deposition (ALD) has been used for many years as an industrial manufacturing method for microprocessors and displays, this versatile technique is finding increased use in the emerging fields of plasmonics and nanobiotechnology. In particular, ALD coatings can modify metallic surfaces to tune their optical and plasmonic properties, to protect them against unwanted oxidation and contamination, or to create biocompatible surfaces. Furthermore, ALD is unique among thin-film deposition techniques in its ability to meet the processing demands for engineering nanoplasmonic devices, offering conformal deposition of dense and ultra-thin films on high-aspect-ratio nanostructures at temperatures below 100 °C. In this review, we present key features of ALD and describe how it could benefit future applications in plasmonics, nanosciences, and biotechnology.
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Affiliation(s)
- Hyungsoon Im
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, United States
| | - Nathan J. Wittenberg
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, United States
| | - Nathan C. Lindquist
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, United States
- Department of Physics, Bethel University, St. Paul, MN 55112, United States
| | - Sang-Hyun Oh
- Laboratory of Nanostructures and Biosensing, Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, United States
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Wittenberg NJ, Im H, Johnson TW, Xu X, Warrington AE, Rodriguez M, Oh SH. Facile assembly of micro- and nanoarrays for sensing with natural cell membranes. ACS Nano 2011; 5:7555-64. [PMID: 21842844 PMCID: PMC3183111 DOI: 10.1021/nn202554t] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Microarray technology has facilitated many powerful high-throughput studies in the fields of genetics and proteomics, among others. However, preparation of microarrays composed of cell-derived membranes with embedded receptors has proven difficult. Here we describe a new method for forming microarrays composed of synthetic lipid vesicles and natural cell membranes. The method is based upon assembly of vesicles and natural membranes into recessed micro- and nanowells and using a polydimethylsiloxane (PDMS) block as a "squeegee." This method is used to assemble phospholipid vesicles into arrays with micrometer and nanoscale dimensions. Native myelin and neuronal lipid raft arrays are also formed in 30 min or less. We show the natural membrane arrays can be used for sensing lipid-protein interactions by detecting cholera toxin binding to ganglioside GM1 in neuronal lipid rafts. In multicomponent arrays myelin can be distinguished from neuronal rafts by antibody binding to cell-specific surface antigens. Finally, myelin arrays formed in gold nanowells are used for surface plasmon resonance sensing. This assembly approach is simple, broadly applicable, and opens up new avenues of research not easily accomplished with standard microarray technology.
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Affiliation(s)
- Nathan J. Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Hyungsoon Im
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Timothy W. Johnson
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA
| | - Xiaohua Xu
- Departments of Neurology and Immunology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Arthur E. Warrington
- Departments of Neurology and Immunology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Moses Rodriguez
- Departments of Neurology and Immunology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, MN 55455, USA
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Im H, Lee SH, Wittenberg NJ, Johnson TW, Lindquist NC, Nagpal P, Norris DJ, Oh SH. Template-stripped smooth Ag nanohole arrays with silica shells for surface plasmon resonance biosensing. ACS Nano 2011; 5:6244-53. [PMID: 21770414 PMCID: PMC3160512 DOI: 10.1021/nn202013v] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Inexpensive, reproducible, and high-throughput fabrication of nanometric apertures in metallic films can benefit many applications in plasmonics, sensing, spectroscopy, lithography, and imaging. Here we use template-stripping to pattern periodic nanohole arrays in optically thick, smooth Ag films with a silicon template made via nanoimprint lithography. Ag is a low-cost material with good optical properties, but it suffers from poor chemical stability and biocompatibility. However, a thin silica shell encapsulating our template-stripped Ag nanoholes facilitates biosensing applications by protecting the Ag from oxidation as well as providing a robust surface that can be readily modified with a variety of biomolecules using well-established silane chemistry. The thickness of the conformal silica shell can be precisely tuned by atomic layer deposition, and a 15 nm thick silica shell can effectively prevent fluorophore quenching. The Ag nanohole arrays with silica shells can also be bonded to polydimethylsiloxane (PDMS) microfluidic channels for fluorescence imaging, formation of supported lipid bilayers, and real-time, label-free SPR sensing. Additionally, the smooth surfaces of the template-stripped Ag films enhance refractive index sensitivity compared with as-deposited, rough Ag films. Because nearly centimeter-sized nanohole arrays can be produced inexpensively without using any additional lithography, etching, or lift-off, this method can facilitate widespread applications of metallic nanohole arrays for plasmonics and biosensing.
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Affiliation(s)
- Hyungsoon Im
- Department of Electrical and Computer Engineering, University of Minnesota, Twin Cities, Minneapolis, MN 55455, U.S.A
| | - Si Hoon Lee
- Department of Biomedical Engineering, University of Minnesota, Twin Cities, Minneapolis, MN 55455, U.S.A
| | - Nathan J. Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, Twin Cities, Minneapolis, MN 55455, U.S.A
| | - Timothy W. Johnson
- Department of Electrical and Computer Engineering, University of Minnesota, Twin Cities, Minneapolis, MN 55455, U.S.A
| | - Nathan C. Lindquist
- Department of Electrical and Computer Engineering, University of Minnesota, Twin Cities, Minneapolis, MN 55455, U.S.A
| | | | - David J. Norris
- Optical Materials Engineering Laboratory, ETH Zürich, Zürich, Switzerland
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, Twin Cities, Minneapolis, MN 55455, U.S.A
- Department of Biomedical Engineering, University of Minnesota, Twin Cities, Minneapolis, MN 55455, U.S.A
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Abstract
This perspective gives an overview of recent developments in surface-enhanced Raman scattering (SERS) for biosensing. We focus this review on SERS papers published in the last 10 years and to specific applications of detecting biological analytes. Both intrinsic and extrinsic SERS biosensing schemes have been employed to detect and identify small molecules, nucleic acids, lipids, peptides, and proteins, as well as for in vivo and cellular sensing. Current SERS substrate technologies along with a series of advancements in surface chemistry, sample preparation, intrinsic/extrinsic signal transduction schemes, and tip-enhanced Raman spectroscopy are discussed. The progress covered herein shows great promise for widespread adoption of SERS biosensing.
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Affiliation(s)
- Kyle C. Bantz
- Department of Chemistry, University of Minnesota, Twin Cities
| | - Audrey F. Meyer
- Department of Chemistry, University of Minnesota, Twin Cities
| | - Nathan J. Wittenberg
- Department of Electrical and Computer Engineering, University of Minnesota, Twin Cities
| | - Hyungsoon Im
- Department of Electrical and Computer Engineering, University of Minnesota, Twin Cities
| | - Özge Kurtuluş
- Department of Chemistry, University of Minnesota, Twin Cities
| | - Si Hoon Lee
- Department of Biomedical Engineering, University of Minnesota, Twin Cities
| | - Nathan C. Lindquist
- Department of Electrical and Computer Engineering, University of Minnesota, Twin Cities
| | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, Twin Cities
- Department of Biomedical Engineering, University of Minnesota, Twin Cities
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Abstract
The size-dependent chemical and physical properties of nanoparticles inspire the design of unique assays and the use of new detection schemes while also offering the opportunity to vastly improve the results achieved when using traditional signal transduction methods. Herein, the most commonly exploited nanoparticle amplification schemes are organized and reviewed on the basis of the detection methods used to monitor the nanoparticle property of interest. The topics covered include the improved signal photostability and brightness of semiconductor quantum dots, the increased extinction coefficient of noble metal nanoparticles, the advantages of having a magnetic label on individual target molecules to facilitate separation, the multiplexing that is enabled with 'barcoded' nanoparticles, and the greatly amplified signals that can be achieved on the basis of conductivity changes, generated current, or simply by adding a 'massive' nanoparticle onto a small molecule target. Common approaches emerge among different nanoparticle materials and detection schemes, and it is also clear that there is still significant opportunity to use nanoparticles in as-yet-unimagined ways to further improve assay and sensor limits of detection.
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Im H, Wittenberg NJ, Lesuffleur A, Lindquist NC, Oh SH. Membrane protein biosensing with plasmonic nanopore arrays and pore-spanning lipid membranes. Chem Sci 2010; 1:688-696. [PMID: 21218136 PMCID: PMC3015192 DOI: 10.1039/c0sc00365d] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Integration of solid-state biosensors and lipid bilayer membranes is important for membrane protein research and drug discovery. In these sensors, it is critical that the solid-state sensing material does not have adverse effects on the conformation or functionality of membrane-bound molecules. In this work, pore-spanning lipid membranes are formed over an array of periodic nanopores in free-standing gold films for surface plasmon resonance (SPR) kinetic binding assays. The ability to perform kinetic assays with a transmembrane protein is demonstrated with α-hemolysin (α-HL). The incorporation of α-HL into the membrane followed by specific antibody binding (anti-α-HL) red-shifts the plasmon resonance of the gold nanopore array, which is optically monitored in real time. Subsequent fluorescence imaging reveals that the antibodies primarily bind in nanopore regions, indicating that α-HL incorporation preferentially occurs into areas of pore-spanning lipid membranes.
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Affiliation(s)
| | | | | | | | - Sang-Hyun Oh
- Department of Electrical and Computer Engineering, University of Minnesota, Minneapolis, Minnesota, 55455, USA. Fax: +1 612 625 4583; Tel: +1 612 625 0125;
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Ge S, Wittenberg NJ, Woo E, Haynes CL. Probing Exocytosis In Blood Platelets. Biophys J 2009. [DOI: 10.1016/j.bpj.2008.12.419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Ge S, Wittenberg NJ, Haynes CL. Quantitative and real-time detection of secretion of chemical messengers from individual platelets. Biochemistry 2008; 47:7020-4. [PMID: 18557631 DOI: 10.1021/bi800792m] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Carbon-fiber microelectrochemical methods were utilized in this study to measure individual exocytotic events of secretion of serotonin and histamine from washed rabbit platelets. The quantal release of serotonin was quantitatively characterized with a delta-granule serotonin concentration of 0.6 M and secretion time course of 7 ms. Additionally, extracellular osmolarity influences quantal size, causing quantal size increases under hypotonic conditions, presumably due to the influx of cytosolic serotonin into the halo region of the delta-granules.
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Affiliation(s)
- Shencheng Ge
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA
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Wittenberg NJ, Zheng L, Winograd N, Ewing AG. Short-chain alcohols promote accelerated membrane distention in a dynamic liposome model of exocytosis. Langmuir 2008; 24:2637-2642. [PMID: 18278956 PMCID: PMC2553711 DOI: 10.1021/la703171u] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We have used amperometric measurements in a model system consisting of two liposomes connected with a membrane nanotube to monitor catechol release during artificial exocytosis and thereby to elucidate the effect of small-chain alcohols on this dynamic membrane process. To determine the rate of membrane shape change, catechol release during membrane distention was monitored amperometrically, and the presence of alcohols in the buffer was shown to accelerate the membrane distention process in a concentration-dependent manner. Compression isotherms for the same lipid composition in the absence and presence of ethanol and 1-propanol were measured to determine how these short-chain alcohols affect the lipid packing in monolayers. The isotherms show a marked decrease in lipid packing density that is dependent on the particular alcohol and its concentration. Comparison of the electrochemical and isotherm results suggests a correlation between decreasing lipid packing density and increasing rates of membrane shape change.
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Affiliation(s)
- Nathan J Wittenberg
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
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