1
|
Fredrikson JP, Domanico LF, Pratt SL, Loveday EK, Taylor MP, Chang CB. Single-cell herpes simplex virus type 1 infection of neurons using drop-based microfluidics reveals heterogeneous replication kinetics. Sci Adv 2024; 10:eadk9185. [PMID: 38416818 PMCID: PMC10901367 DOI: 10.1126/sciadv.adk9185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 01/25/2024] [Indexed: 03/01/2024]
Abstract
Single-cell analyses of viral infections reveal heterogeneity that is not detected by traditional population-level studies. This study applies drop-based microfluidics to investigate the dynamics of herpes simplex virus type 1 (HSV-1) infection of neurons at the single-cell level. We used micrometer-scale Matrigel beads, termed microgels, to culture individual murine superior cervical ganglia (SCG) neurons or epithelial cells. Microgel-cultured cells are encapsulated in individual media-in-oil droplets with a dual-fluorescent reporter HSV-1, enabling real-time observation of viral gene expression and replication. Infection within drops revealed that the kinetics of initial viral gene expression and replication were dependent on the inoculating dose. Notably, increasing inoculating doses led to earlier onset of viral gene expression and more frequent productive viral replication. These observations provide crucial insights into the complexity of HSV-1 infection in neurons and emphasize the importance of studying single-cell outcomes of viral infection. These techniques for cell culture and infection in drops provide a foundation for future virology and neurobiology investigations.
Collapse
Affiliation(s)
- Jacob P. Fredrikson
- Department of Chemical and Biological Engineering, Montana State University, P.O. Box 173920, Bozeman, MT 59717, USA
- Center for Biofilm Engineering, Montana State University, 366 Barnard Hall, Bozeman, MT 59717, USA
| | - Luke F. Domanico
- Department of Microbiology and Cell Biology, Montana State University, P.O. Box 173520, Bozeman, MT 59717, USA
| | - Shawna L. Pratt
- Department of Chemical and Biological Engineering, Montana State University, P.O. Box 173920, Bozeman, MT 59717, USA
- Center for Biofilm Engineering, Montana State University, 366 Barnard Hall, Bozeman, MT 59717, USA
| | - Emma K. Loveday
- Department of Chemical and Biological Engineering, Montana State University, P.O. Box 173920, Bozeman, MT 59717, USA
- Center for Biofilm Engineering, Montana State University, 366 Barnard Hall, Bozeman, MT 59717, USA
| | - Matthew P. Taylor
- Department of Microbiology and Cell Biology, Montana State University, P.O. Box 173520, Bozeman, MT 59717, USA
| | - Connie B. Chang
- Department of Chemical and Biological Engineering, Montana State University, P.O. Box 173920, Bozeman, MT 59717, USA
- Center for Biofilm Engineering, Montana State University, 366 Barnard Hall, Bozeman, MT 59717, USA
- Department of Physiology and Biomedical Engineering, Mayo Clinic, 200 First St. SW, Rochester, MN 55905, USA
| |
Collapse
|
2
|
Fredrikson JP, Brahmachary PP, June RK, Cox LM, Chang CB. Pericellular Matrix Formation and Atomic Force Microscopy of Single Primary Human Chondrocytes Cultured in Alginate Microgels. Adv Biol (Weinh) 2024; 8:e2300268. [PMID: 37688354 PMCID: PMC10843004 DOI: 10.1002/adbi.202300268] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/21/2023] [Indexed: 09/10/2023]
Abstract
One of the main components of articular cartilage is the chondrocyte's pericellular matrix (PCM), which is critical for regulating mechanotransduction, biochemical cues, and healthy cartilage development. Here, individual primary human chondrocytes (PHC) are encapsulated and cultured in 50 µm diameter alginate microgels using drop-based microfluidics. This unique culturing method enables PCM formation and manipulation of individual cells. Over ten days, matrix formation is observed using autofluorescence imaging, and the elastic moduli of isolated cells are measured using AFM. Matrix production and elastic modulus increase are observed for the chondrons cultured in microgels. Furthermore, the elastic modulus of cells grown in microgels increases ≈ten-fold over ten days, nearly reaching the elastic modulus of in vivo PCM. The AFM data is further analyzed using a Gaussian mixture model and shows that the population of PHCs grown in microgels exhibit two distinct populations with elastic moduli averaging 9.0 and 38.0 kPa. Overall, this work shows that microgels provide an excellent culture platform for the growth and isolation of PHCs, enabling PCM formation that is mechanically similar to native PCM. The microgel culture platform presented here has the potential to revolutionize cartilage regeneration procedures through the inclusion of in vitro developed PCM.
Collapse
Affiliation(s)
- Jacob P Fredrikson
- Department of Chemical & Biological Engineering, Montana State University, P.O. Box 173920, Bozeman, MT, 59717, USA
- Center for Biofilm Engineering, Montana State University, P.O. Box 173980, Bozeman, MT, 59717, USA
| | - Priyanka P Brahmachary
- Department of Mechanical & Industrial Engineering, Montana State University, P.O. Box 173800, Bozeman, MT, 59717, USA
| | - Ronald K June
- Department of Mechanical & Industrial Engineering, Montana State University, P.O. Box 173800, Bozeman, MT, 59717, USA
- Department of Microbiology & Cell Biology, Montana State University, P.O. Box 173520, Bozeman, MT, 59717, USA
| | - Lewis M Cox
- Department of Mechanical & Industrial Engineering, Montana State University, P.O. Box 173800, Bozeman, MT, 59717, USA
| | - Connie B Chang
- Department of Chemical & Biological Engineering, Montana State University, P.O. Box 173920, Bozeman, MT, 59717, USA
- Center for Biofilm Engineering, Montana State University, P.O. Box 173980, Bozeman, MT, 59717, USA
- Department of Physiology & Biomedical Engineering, Mayo Clinic, 200 First St. SW, Rochester, MN, 55905, USA
| |
Collapse
|
3
|
Hashimi M, Sebrell TA, Hedges JF, Snyder D, Lyon KN, Byrum SD, Mackintosh SG, Crowley D, Cherne MD, Skwarchuk D, Robison A, Sidar B, Kunze A, Loveday EK, Taylor MP, Chang CB, Wilking JN, Walk ST, Schountz T, Jutila MA, Bimczok D. Antiviral responses in a Jamaican fruit bat intestinal organoid model of SARS-CoV-2 infection. Nat Commun 2023; 14:6882. [PMID: 37898615 PMCID: PMC10613288 DOI: 10.1038/s41467-023-42610-x] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Accepted: 10/16/2023] [Indexed: 10/30/2023] Open
Abstract
Bats are natural reservoirs for several zoonotic viruses, potentially due to an enhanced capacity to control viral infection. However, the mechanisms of antiviral responses in bats are poorly defined. Here we established a Jamaican fruit bat (JFB, Artibeus jamaicensis) intestinal organoid model of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. Upon infection with SARS-CoV-2, increased viral RNA and subgenomic RNA was detected, but no infectious virus was released, indicating that JFB organoids support only limited viral replication but not viral reproduction. SARS-CoV-2 replication was associated with significantly increased gene expression of type I interferons and inflammatory cytokines. Interestingly, SARS-CoV-2 also caused enhanced formation and growth of JFB organoids. Proteomics revealed an increase in inflammatory signaling, cell turnover, cell repair, and SARS-CoV-2 infection pathways. Collectively, our findings suggest that primary JFB intestinal epithelial cells mount successful antiviral interferon responses and that SARS-CoV-2 infection in JFB cells induces protective regenerative pathways.
Collapse
Affiliation(s)
- Marziah Hashimi
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, MT, USA
| | - T Andrew Sebrell
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, MT, USA
| | - Jodi F Hedges
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, MT, USA
| | - Deann Snyder
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, MT, USA
| | - Katrina N Lyon
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, MT, USA
| | - Stephanie D Byrum
- University of Arkansas for Medical Sciences, Department of Biochemistry and Molecular Biology, Little Rock, AR, USA
- Arkansas Children's Research Institute, Little Rock, AR, USA
| | - Samuel G Mackintosh
- University of Arkansas for Medical Sciences, Department of Biochemistry and Molecular Biology, Little Rock, AR, USA
| | - Dan Crowley
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, MT, USA
- Department of Public & Ecosystem Health, Cornell University College of Veterinary Medicine, Ithaca, NY, USA
| | - Michelle D Cherne
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, MT, USA
| | - David Skwarchuk
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, MT, USA
| | - Amanda Robison
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, MT, USA
| | - Barkan Sidar
- Montana State University, Chemical and Biological Engineering Department, Bozeman, MT, USA
- Center for Biofilm Engineering, Bozeman, MT, USA
| | - Anja Kunze
- Montana State University, Electrical and Computer Engineering Department, Bozeman, MT, USA
| | - Emma K Loveday
- Montana State University, Chemical and Biological Engineering Department, Bozeman, MT, USA
- Center for Biofilm Engineering, Bozeman, MT, USA
| | - Matthew P Taylor
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, MT, USA
| | - Connie B Chang
- Montana State University, Chemical and Biological Engineering Department, Bozeman, MT, USA
- Center for Biofilm Engineering, Bozeman, MT, USA
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - James N Wilking
- Montana State University, Chemical and Biological Engineering Department, Bozeman, MT, USA
- Center for Biofilm Engineering, Bozeman, MT, USA
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Seth T Walk
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, MT, USA
| | - Tony Schountz
- Department of Microbiology, Immunology, and Pathology and Center of Vector-Borne Infectious Diseases, Colorado State University, Fort, Collins, CO, USA
| | - Mark A Jutila
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, MT, USA
| | - Diane Bimczok
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, MT, USA.
- Center for Biofilm Engineering, Bozeman, MT, USA.
| |
Collapse
|
4
|
Fredrikson JP, Domanico LF, Pratt SL, Loveday EK, Taylor MP, Chang CB. Single-cell Herpes Simplex Virus type-1 infection of neurons using drop-based microfluidics reveals heterogeneous replication kinetics. bioRxiv 2023:2023.09.18.558333. [PMID: 37790515 PMCID: PMC10542126 DOI: 10.1101/2023.09.18.558333] [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] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Single-cell analyses of viral infections often reveal heterogeneity that is not detected by traditional population-level studies. This study applies drop-based microfluidics to investigate the dynamics of HSV-1 infection of neurons at the single-cell level. We used micron-scale Matrigel beads, termed microgels, to culture individual murine Superior Cervical ganglia (SCG) neurons or epithelial cells. Microgel-cultured cells are subsequently enclosed in individual media-in-oil droplets with a dual fluorescent-reporter HSV-1, enabling real-time observation of viral gene expression and replication. Infection within drops revealed that the kinetics of initial viral gene expression and replication were dependent on the inoculating dose. Notably, increasing inoculating doses led to earlier onset of viral gene expression and more frequent productive viral replication. These observations provide crucial insights into the complexity of HSV-1 infection in neurons and emphasize the importance of studying single-cell outcomes of viral infection. The innovative techniques presented here for cell culture and infection in drops provide a foundation for future virology and neurobiology investigations.
Collapse
Affiliation(s)
- Jacob P. Fredrikson
- Department of Chemical & Biological Engineering, Montana State University, P.O. Box 173920, Bozeman, MT 59717, USA
- Center for Biofilm Engineering, Montana State University, 366 Barnard Hall, Bozeman, MT 59717, USA
| | - Luke F. Domanico
- Department of Microbiology & Cell Biology, Montana State University, P.O. Box 173520, Bozeman, MT 59717, USA
| | - Shawna L. Pratt
- Department of Chemical & Biological Engineering, Montana State University, P.O. Box 173920, Bozeman, MT 59717, USA
- Center for Biofilm Engineering, Montana State University, 366 Barnard Hall, Bozeman, MT 59717, USA
| | - Emma K. Loveday
- Department of Chemical & Biological Engineering, Montana State University, P.O. Box 173920, Bozeman, MT 59717, USA
- Center for Biofilm Engineering, Montana State University, 366 Barnard Hall, Bozeman, MT 59717, USA
| | - Matthew P. Taylor
- Department of Microbiology & Cell Biology, Montana State University, P.O. Box 173520, Bozeman, MT 59717, USA
| | - Connie B. Chang
- Department of Chemical & Biological Engineering, Montana State University, P.O. Box 173920, Bozeman, MT 59717, USA
- Center for Biofilm Engineering, Montana State University, 366 Barnard Hall, Bozeman, MT 59717, USA
- Department of Physiology & Biomedical Engineering, Mayo Clinic, 200 First St. SW, Rochester, MN 55905, USA
| |
Collapse
|
5
|
Zath GK, Sperling RA, Hoffman CW, Bikos DA, Abbasi R, Abate AR, Weitz DA, Chang CB. Rapid parallel generation of a fluorescently barcoded drop library from a microtiter plate using the plate-interfacing parallel encapsulation (PIPE) chip. Lab Chip 2022; 22:4735-4745. [PMID: 36367139 PMCID: PMC10016142 DOI: 10.1039/d2lc00909a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
In drop-based microfluidics, an aqueous sample is partitioned into drops using individual pump sources that drive water and oil into a drop-making device. Parallelization of drop-making devices is necessary to achieve high-throughput screening of multiple experimental conditions, especially in time-sensitive studies. Here, we present the plate-interfacing parallel encapsulation (PIPE) chip, a microfluidic chip designed to generate 50 to 90 μm diameter drops of up to 96 different conditions in parallel by interfacing individual drop makers with a standard 384-well microtiter plate. The PIPE chip is used to generate two types of optically barcoded drop libraries consisting of two-color fluorescent particle combinations: a library of 24 microbead barcodes and a library of 192 quantum dot barcodes. Barcoded combinations in the drop libraries are rapidly measured within a microfluidic device using fluorescence detection and distinct barcoded populations in the fluorescence drop data are identified using DBSCAN data clustering. Signal analysis reveals that particle size defines the source of dominant noise present in the fluorescence intensity distributions of the barcoded drop populations, arising from Poisson loading for microbeads and shot noise for quantum dots. A barcoded population from a drop library is isolated using fluorescence-activated drop sorting, enabling downstream analysis of drop contents. The PIPE chip can improve multiplexed high-throughput assays by enabling simultaneous encapsulation of barcoded samples stored in a microtiter plate and reducing sample preparation time.
Collapse
Affiliation(s)
- Geoffrey K Zath
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA.
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA
| | - Ralph A Sperling
- Department of Physics, School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
- Fraunhofer Institute for Microengineering and Microsystems IMM, Mainz, Germany
| | - Carter W Hoffman
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA.
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Dimitri A Bikos
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA.
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA
| | - Reha Abbasi
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA.
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA
| | - Adam R Abate
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
| | - David A Weitz
- Department of Physics, School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
- Wyss Institute for Biologically Inspired Engineering at Harvard University, Boston, MA, USA
| | - Connie B Chang
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA.
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| |
Collapse
|
6
|
Loveday EK, Sanchez HS, Thomas MM, Chang CB. Single-Cell Infection of Influenza A Virus Using Drop-Based Microfluidics. Microbiol Spectr 2022; 10:e0099322. [PMID: 36125315 PMCID: PMC9603537 DOI: 10.1128/spectrum.00993-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [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: 04/13/2022] [Accepted: 08/22/2022] [Indexed: 12/30/2022] Open
Abstract
Drop-based microfluidics has revolutionized single-cell studies and can be applied toward analyzing tens of thousands to millions of single cells and their products contained within picoliter-sized drops. Drop-based microfluidics can shed insight into single-cell virology, enabling higher-resolution analysis of cellular and viral heterogeneity during viral infection. In this work, individual A549, MDCK, and siat7e cells were infected with influenza A virus (IAV) and encapsulated into 100-μm-size drops. Initial studies of uninfected cells encapsulated in drops demonstrated high cell viability and drop stability. Cell viability of uninfected cells in the drops remained above 75%, and the average drop radii changed by less than 3% following cell encapsulation and incubation over 24 h. Infection parameters were analyzed over 24 h from individually infected cells in drops. The number of IAV viral genomes and infectious viruses released from A549 and MDCK cells in drops was not significantly different from bulk infection as measured by reverse transcriptase quantitative PCR (RT-qPCR) and plaque assay. The application of drop-based microfluidics in this work expands the capacity to propagate IAV viruses and perform high-throughput analyses of individually infected cells. IMPORTANCE Drop-based microfluidics is a cutting-edge tool in single-cell research. Here, we used drop-based microfluidics to encapsulate thousands of individual cells infected with influenza A virus within picoliter-sized drops. Drop stability, cell loading, and cell viability were quantified from three different cell lines that support influenza A virus propagation. Similar levels of viral progeny as determined by RT-qPCR and plaque assay were observed from encapsulated cells in drops compared to bulk culture. This approach enables the ability to propagate influenza A virus from encapsulated cells, allowing for future high-throughput analysis of single host cell interactions in isolated microenvironments over the course of the viral life cycle.
Collapse
Affiliation(s)
- Emma Kate Loveday
- Center for Biofilm Engineering, Montana State University, Bozeman, Montana, USA
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, Montana, USA
| | - Humberto S. Sanchez
- Center for Biofilm Engineering, Montana State University, Bozeman, Montana, USA
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, Montana, USA
| | - Mallory M. Thomas
- Center for Biofilm Engineering, Montana State University, Bozeman, Montana, USA
- Microbiology and Cell Biology, Montana State University, Bozeman, Montana, USA
| | - Connie B. Chang
- Center for Biofilm Engineering, Montana State University, Bozeman, Montana, USA
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, Montana, USA
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| |
Collapse
|
7
|
Mahdieh Z, Cherne MD, Fredrikson JP, Sidar B, Sanchez HS, Chang CB, Bimczok D, Wilking JN. Granular Matrigel: restructuring a trusted extracellular matrix material for improved permeability. Biomed Mater 2022; 17. [PMID: 35609584 DOI: 10.1088/1748-605x/ac7306] [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: 02/01/2022] [Accepted: 05/24/2022] [Indexed: 11/11/2022]
Abstract
Matrigel is a polymeric extracellular matrix material produced by mouse cancer cells. Over the past four decades, Matrigel has been shown to support a wide variety of two- and three-dimensional cell and tissue culture applications including organoids. Despite widespread use, transport of molecules, cells, and colloidal particles through Matrigel can be limited. These limitations restrict cell growth, viability, and function and limit Matrigel applications. A strategy to improve transport through a hydrogel without modifying the chemistry or composition of the gel is to physically restructure the material into microscopic microgels and then pack them together to form a porous material. These 'granular' hydrogels have been created using a variety of synthetic hydrogels, but granular hydrogels composed of Matrigel have not yet been reported. Here we present a drop-based microfluidics approach for structuring Matrigel into a three-dimensional, mesoporous material composed of packed Matrigel microgels, which we call granular Matrigel. We show that restructuring Matrigel in this manner enhances the transport of colloidal particles and human dendritic cells (DCs) through the gel while providing sufficient mechanical support for culture of human gastric organoids (HGOs) and co-culture of human DCs with HGOs.
Collapse
Affiliation(s)
- Zahra Mahdieh
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, United States of America.,Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States of America
| | - Michelle D Cherne
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, United States of America
| | - Jacob P Fredrikson
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, United States of America.,Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States of America
| | - Barkan Sidar
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, United States of America.,Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States of America
| | - Humberto S Sanchez
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, United States of America.,Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States of America
| | - Connie B Chang
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, United States of America.,Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States of America
| | - Diane Bimczok
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, United States of America
| | - James N Wilking
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, United States of America.,Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States of America
| |
Collapse
|
8
|
Cherne MD, Sidar B, Sebrell TA, Sanchez HS, Heaton K, Kassama FJ, Roe MM, Gentry AB, Chang CB, Walk ST, Jutila M, Wilking JN, Bimczok D. A Synthetic Hydrogel, VitroGel ® ORGANOID-3, Improves Immune Cell-Epithelial Interactions in a Tissue Chip Co-Culture Model of Human Gastric Organoids and Dendritic Cells. Front Pharmacol 2021; 12:707891. [PMID: 34552484 PMCID: PMC8450338 DOI: 10.3389/fphar.2021.707891] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 08/16/2021] [Indexed: 12/15/2022] Open
Abstract
Immunosurveillance of the gastrointestinal epithelium by mononuclear phagocytes (MNPs) is essential for maintaining gut health. However, studying the complex interplay between the human gastrointestinal epithelium and MNPs such as dendritic cells (DCs) is difficult, since traditional cell culture systems lack complexity, and animal models may not adequately represent human tissues. Microphysiological systems, or tissue chips, are an attractive alternative for these investigations, because they model functional features of specific tissues or organs using microscale culture platforms that recreate physiological tissue microenvironments. However, successful integration of multiple of tissue types on a tissue chip platform to reproduce physiological cell-cell interactions remains a challenge. We previously developed a tissue chip system, the gut organoid flow chip (GOFlowChip), for long term culture of 3-D pluripotent stem cell-derived human intestinal organoids. Here, we optimized the GOFlowChip platform to build a complex microphysiological immune-cell-epithelial cell co-culture model in order to study DC-epithelial interactions in human stomach. We first tested different tubing materials and chip configurations to optimize DC loading onto the GOFlowChip and demonstrated that DC culture on the GOFlowChip for up to 20 h did not impact DC activation status or viability. However, Transwell chemotaxis assays and live confocal imaging revealed that Matrigel, the extracellular matrix (ECM) material commonly used for organoid culture, prevented DC migration towards the organoids and the establishment of direct MNP-epithelial contacts. Therefore, we next evaluated DC chemotaxis through alternative ECM materials including Matrigel-collagen mixtures and synthetic hydrogels. A polysaccharide-based synthetic hydrogel, VitroGel®-ORGANOID-3 (V-ORG-3), enabled significantly increased DC chemotaxis through the matrix, supported organoid survival and growth, and did not significantly alter DC activation or viability. On the GOFlowChip, DCs that were flowed into the chip migrated rapidly through the V-ORG matrix and reached organoids embedded deep within the chip, with increased interactions between DCs and gastric organoids. The successful integration of DCs and V-ORG-3 embedded gastric organoids into the GOFlowChip platform now permits real-time imaging of MNP-epithelial interactions and other investigations of the complex interplay between gastrointestinal MNPs and epithelial cells in their response to pathogens, candidate drugs and mucosal vaccines.
Collapse
Affiliation(s)
- Michelle D Cherne
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, United States
| | - Barkan Sidar
- Chemical and Biological Engineering Department and Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States
| | - T Andrew Sebrell
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, United States
| | - Humberto S Sanchez
- Chemical and Biological Engineering Department and Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States
| | - Kody Heaton
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, United States
| | - Francis J Kassama
- Department of Chemistry and Biochemistry, Bowdoin College, Brunswick, ME, United States
| | - Mandi M Roe
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, United States
| | - Andrew B Gentry
- Bozeman GI Clinic, Deaconess Hospital, Bozeman, MT, United States
| | - Connie B Chang
- Chemical and Biological Engineering Department and Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States
| | - Seth T Walk
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, United States
| | - Mark Jutila
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, United States
| | - James N Wilking
- Chemical and Biological Engineering Department and Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States
| | - Diane Bimczok
- Department of Microbiology and Cell Biology, Montana State University, Bozeman, MT, United States
| |
Collapse
|
9
|
Moore KJM, Cahill J, Aidelberg G, Aronoff R, Bektaş A, Bezdan D, Butler DJ, Chittur SV, Codyre M, Federici F, Tanner NA, Tighe SW, True R, Ware SB, Wyllie AL, Afshin EE, Bendesky A, Chang CB, Dela Rosa R, Elhaik E, Erickson D, Goldsborough AS, Grills G, Hadasch K, Hayden A, Her SY, Karl JA, Kim CH, Kriegel AJ, Kunstman T, Landau Z, Land K, Langhorst BW, Lindner AB, Mayer BE, McLaughlin LA, McLaughlin MT, Molloy J, Mozsary C, Nadler JL, D'Silva M, Ng D, O'Connor DH, Ongerth JE, Osuolale O, Pinharanda A, Plenker D, Ranjan R, Rosbash M, Rotem A, Segarra J, Schürer S, Sherrill-Mix S, Solo-Gabriele H, To S, Vogt MC, Yu AD, Mason CE. Loop-Mediated Isothermal Amplification Detection of SARS-CoV-2 and Myriad Other Applications. J Biomol Tech 2021; 32:228-275. [PMID: 35136384 PMCID: PMC8802757 DOI: 10.7171/jbt.21-3203-017] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [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: 12/23/2022]
Abstract
As the second year of the COVID-19 pandemic begins, it remains clear that a massive increase in the ability to test for SARS-CoV-2 infections in a myriad of settings is critical to controlling the pandemic and to preparing for future outbreaks. The current gold standard for molecular diagnostics is the polymerase chain reaction (PCR), but the extraordinary and unmet demand for testing in a variety of environments means that both complementary and supplementary testing solutions are still needed. This review highlights the role that loop-mediated isothermal amplification (LAMP) has had in filling this global testing need, providing a faster and easier means of testing, and what it can do for future applications, pathogens, and the preparation for future outbreaks. This review describes the current state of the art for research of LAMP-based SARS-CoV-2 testing, as well as its implications for other pathogens and testing. The authors represent the global LAMP (gLAMP) Consortium, an international research collective, which has regularly met to share their experiences on LAMP deployment and best practices; sections are devoted to all aspects of LAMP testing, including preanalytic sample processing, target amplification, and amplicon detection, then the hardware and software required for deployment are discussed, and finally, a summary of the current regulatory landscape is provided. Included as well are a series of first-person accounts of LAMP method development and deployment. The final discussion section provides the reader with a distillation of the most validated testing methods and their paths to implementation. This review also aims to provide practical information and insight for a range of audiences: for a research audience, to help accelerate research through sharing of best practices; for an implementation audience, to help get testing up and running quickly; and for a public health, clinical, and policy audience, to help convey the breadth of the effect that LAMP methods have to offer.
Collapse
Affiliation(s)
- Keith J M Moore
- School of Science and Engineering, Ateneo de Manila University, Quezon City 1108, Philippines
| | | | - Guy Aidelberg
- Université de Paris, INSERM U1284, Center for Research and Interdisciplinarity (CRI), 75006 Paris, France
- Just One Giant Lab, Centre de Recherches Interdisciplinaires (CRI), 75004 Paris, France
| | - Rachel Aronoff
- Just One Giant Lab, Centre de Recherches Interdisciplinaires (CRI), 75004 Paris, France
- Action for Genomic Integrity Through Research! (AGiR!), Lausanne, Switzerland
- Association Hackuarium, Lausanne, Switzerland
| | - Ali Bektaş
- Oakland Genomics Center, Oakland, CA 94609, USA
| | - Daniela Bezdan
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, 72076 Tübingen, Germany
- NGS Competence Center Tübingen (NCCT), University of Tübingen, 72076 Tübingen, Germany
- Poppy Health, Inc, San Francisco, CA 94158, USA
- Institute of Medical Virology and Epidemiology of Viral Diseases, University Hospital, 72076 Tübingen, Germany
| | - Daniel J Butler
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY 10065, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY 10065, USA
| | - Sridar V Chittur
- Center for Functional Genomics, Department of Biomedical Sciences, School of Public Health, University at Albany, State University of New York, Rensselaer, 12222, USA
| | - Martin Codyre
- GiantLeap Biotechnology Ltd, Wicklow A63 Kv91, Ireland
| | - Fernan Federici
- ANID, Millennium Science Initiative Program, Millennium Institute for Integrative Biology (iBio), Institute for Biological and Medical Engineering, Schools of Engineering, Biology and Medicine, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
| | | | | | - Randy True
- FloodLAMP Biotechnologies, San Carlos, CA 94070, USA
| | - Sarah B Ware
- Just One Giant Lab, Centre de Recherches Interdisciplinaires (CRI), 75004 Paris, France
- BioBlaze Community Bio Lab, 1800 W Hawthorne Ln, Ste J-1, West Chicago, IL 60185, USA
- Blossom Bio Lab, 1800 W Hawthorne Ln, Ste K-2, West Chicago, IL 60185, USA
| | - Anne L Wyllie
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
| | - Evan E Afshin
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY 10065, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY 10065, USA
- The WorldQuant Initiative for Quantitative Prediction, Weill Cornell Medicine, New York, NY 10065, USA
| | - Andres Bendesky
- Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, NY 10027, USA
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Connie B Chang
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, 59717, USA
- Center for Biofilm Engineering, Montana State University, Bozeman, 59717, USA
| | - Richard Dela Rosa
- School of Science and Engineering, Ateneo de Manila University, Quezon City 1108, Philippines
| | - Eran Elhaik
- Department of Biology, Lund University, Sölvegatan 35, Lund, Sweden
| | - David Erickson
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14850, USA
| | | | - George Grills
- Department of Microbiology, University of Pennsylvania, Philadelphia, 19104, USA
| | - Kathrin Hadasch
- Université de Paris, INSERM U1284, Center for Research and Interdisciplinarity (CRI), 75006 Paris, France
- Department of Biology, Membrane Biophysics, Technische Universität Darmstadt, 64289 Darmstadt, Germany
- Lab3 eV, Labspace Darmstadt, 64295 Darmstadt, Germany
- IANUS Verein für Friedensorientierte Technikgestaltung eV, 64289 Darmstadt, Germany
| | - Andrew Hayden
- Center for Functional Genomics, Department of Biomedical Sciences, School of Public Health, University at Albany, State University of New York, Rensselaer, 12222, USA
| | | | - Julie A Karl
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Madison 53705, USA
| | | | | | | | - Zeph Landau
- Department of Computer Science, University of California, Berkeley, Berkeley, 94720, USA
| | - Kevin Land
- Mologic, Centre for Advanced Rapid Diagnostics, (CARD), Bedford Technology Park, Thurleigh MK44 2YA, England
- Department of Electrical, Electronic and Computer Engineering, University of Pretoria, 0028 Pretoria, South Africa
| | | | - Ariel B Lindner
- Université de Paris, INSERM U1284, Center for Research and Interdisciplinarity (CRI), 75006 Paris, France
| | - Benjamin E Mayer
- Department of Biology, Membrane Biophysics, Technische Universität Darmstadt, 64289 Darmstadt, Germany
- Lab3 eV, Labspace Darmstadt, 64295 Darmstadt, Germany
| | | | - Matthew T McLaughlin
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Madison 53705, USA
| | - Jenny Molloy
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB3 0AS, England
| | - Christopher Mozsary
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY 10065, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY 10065, USA
| | - Jerry L Nadler
- Department of Pharmacology, New York Medical College, Valhalla, 10595, USA
| | - Melinee D'Silva
- Department of Pharmacology, New York Medical College, Valhalla, 10595, USA
| | - David Ng
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - David H O'Connor
- Department of Pathology and Laboratory Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, Madison 53705, USA
| | - Jerry E Ongerth
- University of Wollongong, Environmental Engineering, Wollongong NSW 2522, Australia
| | - Olayinka Osuolale
- Applied Environmental Metagenomics and Infectious Diseases Research (AEMIDR), Department of Biological Sciences, Elizade University, Ilara Mokin, Nigeria
| | - Ana Pinharanda
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Dennis Plenker
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Ravi Ranjan
- Genomics Resource Laboratory, Institute for Applied Life Sciences, University of Massachusetts, Amherst, 01003, USA
| | - Michael Rosbash
- Howard Hughes Medical Institute and Department of Biology, Brandeis University, Waltham, MA 02453, USA
| | | | | | | | - Scott Sherrill-Mix
- Department of Microbiology, University of Pennsylvania, Philadelphia, 19104, USA
| | | | - Shaina To
- School of Science and Engineering, Ateneo de Manila University, Quezon City 1108, Philippines
| | - Merly C Vogt
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Albert D Yu
- Howard Hughes Medical Institute and Department of Biology, Brandeis University, Waltham, MA 02453, USA
| | - Christopher E Mason
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY 10065, USA
- The HRH Prince Alwaleed Bin Talal Bin Abdulaziz Alsaud Institute for Computational Biomedicine, Weill Cornell Medicine, New York, NY 10065, USA
- The WorldQuant Initiative for Quantitative Prediction, Weill Cornell Medicine, New York, NY 10065, USA
- The Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA
| |
Collapse
|
10
|
LeFevre TB, Bikos DA, Chang CB, Wilking JN. Measuring colloid-surface interaction forces in parallel using fluorescence centrifuge force microscopy. Soft Matter 2021; 17:6326-6336. [PMID: 34136896 DOI: 10.1039/d1sm00461a] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Interactions between colloidal-scale structures govern the physical properties of soft and biological materials, and knowledge of the forces associated with these interactions is critical for understanding and controlling these materials. A common approach to quantify colloidal interactions is to measure the interaction forces between colloids and a fixed surface. The centrifuge force microscope (CFM), a miniaturized microscope inside a centrifuge, is capable of performing hundreds of force measurements in parallel over a wide force range (10-2 to 104 pN), but CFM instruments are not widely used to measure colloid-surface interaction forces. In addition, current CFM instruments rely on brightfield illumination and are not capable of fluorescence microscopy. Here we present a fluorescence CFM (F-CFM) that combines both fluorescence and brightfield microscopy and demonstrate its use for measuring microscale colloidal-surface interaction forces. The F-CFM operates at speeds up to 5000 RPM, 2.5× faster than those previously reported, yielding a 6.25× greater maximum force than previous instruments. A battery-powered GoPro video camera enables real-time viewing of the microscopy video on a mobile device, and frequency analysis of the audio signal correlates centrifuge rotational speed with the video signal. To demonstrate the capability of the F-CFM, we measure the force required to detach hundreds of electrostatically stabilized colloidal microspheres attached to a charged glass surface as a function of ionic strength and compare the resulting force distributions with an approximated DLVO theory. The F-CFM will enable microscale force measurements to be correlated with fluorescence imaging in soft and biological systems.
Collapse
Affiliation(s)
- Thomas B LeFevre
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA. and Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
| | - Dimitri A Bikos
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA. and Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
| | - Connie B Chang
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA. and Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
| | - James N Wilking
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, USA. and Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
| |
Collapse
|
11
|
Loveday EK, Hain KS, Kochetkova I, Hedges JF, Robison A, Snyder DT, Brumfield SK, Young MJ, Jutila MA, Chang CB, Taylor MP. Effect of Inactivation Methods on SARS-CoV-2 Virion Protein and Structure. Viruses 2021; 13:562. [PMID: 33810401 PMCID: PMC8066162 DOI: 10.3390/v13040562] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [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: 03/09/2021] [Accepted: 03/22/2021] [Indexed: 12/31/2022] Open
Abstract
The risk posed by Severe Acute Respiratory Syndrome Coronavirus -2 (SARS-CoV-2) dictates that live-virus research is conducted in a biosafety level 3 (BSL3) facility. Working with SARS-CoV-2 at lower biosafety levels can expedite research yet requires the virus to be fully inactivated. In this study, we validated and compared two protocols for inactivating SARS-CoV-2: heat treatment and ultraviolet irradiation. The two methods were optimized to render the virus completely incapable of infection while limiting the destructive effects of inactivation. We observed that 15 min of incubation at 65 °C completely inactivates high titer viral stocks. Complete inactivation was also achieved with minimal amounts of UV power (70,000 µJ/cm2), which is 100-fold less power than comparable studies. Once validated, the two methods were then compared for viral RNA quantification, virion purification, and antibody detection assays. We observed that UV irradiation resulted in a 2-log reduction of detectable genomes compared to heat inactivation. Protein yield following virion enrichment was equivalent for all inactivation conditions, but the quality of resulting viral proteins and virions were differentially impacted depending on inactivation method and time. Here, we outline the strengths and weaknesses of each method so that investigators might choose the one which best meets their research goals.
Collapse
Affiliation(s)
- Emma K. Loveday
- Department of Chemical & Biological Engineering, Montana State University, Bozeman, MT 59717, USA; (E.K.L.); (C.B.C.)
| | - Kyle S. Hain
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA; (K.S.H.); (I.K.); (J.F.H.); (A.R.); (D.T.S.); (M.A.J.)
| | - Irina Kochetkova
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA; (K.S.H.); (I.K.); (J.F.H.); (A.R.); (D.T.S.); (M.A.J.)
| | - Jodi F. Hedges
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA; (K.S.H.); (I.K.); (J.F.H.); (A.R.); (D.T.S.); (M.A.J.)
| | - Amanda Robison
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA; (K.S.H.); (I.K.); (J.F.H.); (A.R.); (D.T.S.); (M.A.J.)
| | - Deann T. Snyder
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA; (K.S.H.); (I.K.); (J.F.H.); (A.R.); (D.T.S.); (M.A.J.)
| | - Susan K. Brumfield
- Department of Plant Science and Plant Pathology, Montana State University; Bozeman, MT 59717, USA; (S.K.B.); (M.J.Y.)
| | - Mark J. Young
- Department of Plant Science and Plant Pathology, Montana State University; Bozeman, MT 59717, USA; (S.K.B.); (M.J.Y.)
| | - Mark A. Jutila
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA; (K.S.H.); (I.K.); (J.F.H.); (A.R.); (D.T.S.); (M.A.J.)
| | - Connie B. Chang
- Department of Chemical & Biological Engineering, Montana State University, Bozeman, MT 59717, USA; (E.K.L.); (C.B.C.)
| | - Matthew P. Taylor
- Department of Microbiology & Immunology, Montana State University, Bozeman, MT 59717, USA; (K.S.H.); (I.K.); (J.F.H.); (A.R.); (D.T.S.); (M.A.J.)
| |
Collapse
|
12
|
Loveday EK, Zath GK, Bikos DA, Jay ZJ, Chang CB. Screening of Additive Formulations Enables Off-Chip Drop Reverse Transcription Quantitative Polymerase Chain Reaction of Single Influenza A Virus Genomes. Anal Chem 2021; 93:4365-4373. [PMID: 33635052 PMCID: PMC10016143 DOI: 10.1021/acs.analchem.0c03455] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The miniaturization of polymerase chain reaction (PCR) using drop-based microfluidics allows for amplification of single nucleic acids in aqueous picoliter-sized drops. Accurate data collection during PCR requires that drops remain stable to coalescence during thermocycling and drop contents are retained. Following systematic testing of known PCR additives, we identified an optimized formulation of 1% w/v Tween-20, 0.8 μg/μL bovine serum albumin, 1 M betaine in the aqueous phase, and 3 wt % (w/w) of the polyethylene glycol-perfluoropolyether2 surfactant in the oil phase of 50 μm diameter drops that maintains drop stability and prevents dye transport. This formulation enables a method we call off-chip drop reverse transcription quantitative PCR (OCD RT-qPCR) in which drops are thermocycled in a qPCR machine and sampled at various cycle numbers "off-chip", or outside of a microfluidic chip. qPCR amplification curves constructed from hundreds of individual drops using OCD RT-qPCR and imaged using epifluorescence microscopy correlate with amplification curves of ≈300,000 drops thermocycled using a qPCR machine. To demonstrate the utility of OCD RT-qPCR, influenza A virus (IAV) RNA was detected down to a single viral genome copy per drop, or 0.320 cpd. This work was extended to perform multiplexed detection of IAV M gene RNA and cellular β-actin DNA in drops, and direct amplification of IAV genomes from infected cells without a separate RNA extraction step. The optimized additive formulation and the OCD-qPCR method allow for drop-based RT-qPCR without complex devices and demonstrate the ability to quantify individual or rare nucleic acid species within drops with minimal processing.
Collapse
Affiliation(s)
- Emma Kate Loveday
- Center for Biofilm Engineering and the Department of Chemical and Biological Engineering, Montana State University, Bozeman, Montana 59717, United States
| | - Geoffrey K Zath
- Center for Biofilm Engineering and the Department of Chemical and Biological Engineering, Montana State University, Bozeman, Montana 59717, United States
| | - Dimitri A Bikos
- Center for Biofilm Engineering and the Department of Chemical and Biological Engineering, Montana State University, Bozeman, Montana 59717, United States
| | - Zackary J Jay
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, United States
| | - Connie B Chang
- Center for Biofilm Engineering and the Department of Chemical and Biological Engineering, Montana State University, Bozeman, Montana 59717, United States
| |
Collapse
|
13
|
Zambare NM, Naser NY, Gerlach R, Chang CB. Mineralogy of microbially induced calcium carbonate precipitates formed using single cell drop-based microfluidics. Sci Rep 2020; 10:17535. [PMID: 33067478 PMCID: PMC7568533 DOI: 10.1038/s41598-020-73870-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [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: 05/28/2020] [Accepted: 09/21/2020] [Indexed: 11/28/2022] Open
Abstract
Microbe-mineral interactions are ubiquitous and can facilitate major biogeochemical reactions that drive dynamic Earth processes such as rock formation. One example is microbially induced calcium carbonate precipitation (MICP) in which microbial activity leads to the formation of calcium carbonate precipitates. A majority of MICP studies have been conducted at the mesoscale but fundamental questions persist regarding the mechanisms of cell encapsulation and mineral polymorphism. Here, we are the first to investigate and characterize precipitates on the microscale formed by MICP starting from single ureolytic E. coli MJK2 cells in 25 µm diameter drops. Mineral precipitation was observed over time and cells surrounded by calcium carbonate precipitates were observed under hydrated conditions. Using Raman microspectroscopy, amorphous calcium carbonate (ACC) was observed first in the drops, followed by vaterite formation. ACC and vaterite remained stable for up to 4 days, possibly due to the presence of organics. The vaterite precipitates exhibited a dense interior structure with a grainy exterior when examined using electron microscopy. Autofluorescence of these precipitates was observed possibly indicating the development of a calcite phase. The developed approach provides an avenue for future investigations surrounding fundamental processes such as precipitate nucleation on bacteria, microbe-mineral interactions, and polymorph transitions.
Collapse
Affiliation(s)
- Neerja M Zambare
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, 59717, USA
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, 59717, USA
| | - Nada Y Naser
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, 59717, USA
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, 59717, USA
- Department of Chemical Engineering, University of Washington, Seattle, WA, 98195, USA
| | - Robin Gerlach
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, 59717, USA.
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, 59717, USA.
| | - Connie B Chang
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, 59717, USA.
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, 59717, USA.
| |
Collapse
|
14
|
Pratt SL, Zath GK, Akiyama T, Williamson KS, Franklin MJ, Chang CB. DropSOAC: Stabilizing Microfluidic Drops for Time-Lapse Quantification of Single-Cell Bacterial Physiology. Front Microbiol 2019; 10:2112. [PMID: 31608020 PMCID: PMC6774397 DOI: 10.3389/fmicb.2019.02112] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Accepted: 08/27/2019] [Indexed: 12/19/2022] Open
Abstract
The physiological heterogeneity of cells within a microbial population imparts resilience to stresses such as antimicrobial treatments and nutrient limitation. This resilience is partially due to a subpopulation of cells that can survive such stresses and regenerate the community. Microfluidic approaches now provide a means to study microbial physiology and bacterial heterogeneity at the single cell level, improving our ability to isolate and examine these subpopulations. Drop-based microfluidics provides a high-throughput approach to study individual cell physiology within bacterial populations. Using this approach, single cells are isolated from the population and encapsulated in growth medium dispersed in oil using a 15 μm diameter drop making microfluidic device. The drops are arranged as a packed monolayer inside a polydimethylsiloxane (PDMS) microfluidic device. Growth of thousands of individual cells in identical microenvironments can then be imaged using confocal laser scanning microscopy (CLSM). A challenge for this approach has been the maintenance of drop stability during extended time-lapse imaging. In particular, the drops do not maintain their volume over time during incubation in PDMS devices, due to fluid transport into the porous PDMS surroundings. Here, we present a strategy for PDMS device preparation that stabilizes drop position and volume within a drop array on a microfluidic chip for over 20 h. The stability of water-in-oil drops is maintained by soaking the device in a reservoir containing both water and oil in thermodynamic equilibrium. This ensures that phase equilibrium of the drop emulsion fluids within the porous PDMS material is maintained during drop incubation and imaging. We demonstrate the utility of this approach, which we label DropSOAC (Drop Stabilization On A Chip), for time-lapse studies of bacterial growth. We characterize growth of Pseudomonas aeruginosa and its Δhpf mutant derivative during resuscitation and growth following starvation. We demonstrate that growth rate and lag time heterogeneity of hundreds of individual bacterial cells can be determined starting from single isolated cells. The results show that the DropSOAC capsule provides a high-throughput approach toward studies of microbial physiology at the single cell level, and can be used to characterize physiological differences of cells from within a larger population.
Collapse
Affiliation(s)
- Shawna L. Pratt
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, United States
| | - Geoffrey K. Zath
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, United States
| | - Tatsuya Akiyama
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
| | - Kerry S. Williamson
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
| | - Michael J. Franklin
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
| | - Connie B. Chang
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, United States
- Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT, United States
| |
Collapse
|
15
|
Rotem A, Serohijos AWR, Chang CB, Wolfe JT, Fischer AE, Mehoke TS, Zhang H, Tao Y, Lloyd Ung W, Choi JM, Rodrigues JV, Kolawole AO, Koehler SA, Wu S, Thielen PM, Cui N, Demirev PA, Giacobbi NS, Julian TR, Schwab K, Lin JS, Smith TJ, Pipas JM, Wobus CE, Feldman AB, Weitz DA, Shakhnovich EI. Evolution on the Biophysical Fitness Landscape of an RNA Virus. Mol Biol Evol 2019; 35:2390-2400. [PMID: 29955873 PMCID: PMC6188569 DOI: 10.1093/molbev/msy131] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Viral evolutionary pathways are determined by the fitness landscape, which maps viral genotype to fitness. However, a quantitative description of the landscape and the evolutionary forces on it remain elusive. Here, we apply a biophysical fitness model based on capsid folding stability and antibody binding affinity to predict the evolutionary pathway of norovirus escaping a neutralizing antibody. The model is validated by experimental evolution in bulk culture and in a drop-based microfluidics that propagates millions of independent small viral subpopulations. We demonstrate that along the axis of binding affinity, selection for escape variants and drift due to random mutations have the same direction, an atypical case in evolution. However, along folding stability, selection and drift are opposing forces whose balance is tuned by viral population size. Our results demonstrate that predictable epistatic tradeoffs between molecular traits of viral proteins shape viral evolution.
Collapse
Affiliation(s)
- Assaf Rotem
- Department of Physics, School of Engineering and Applied Sciences, Harvard University, Cambridge, MA
| | - Adrian W R Serohijos
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA.,Département de Biochimie et Centre Robert-Cedergren en Bioinformatique et Génomique, Université de Montréal, Montréal, QC, Canada
| | - Connie B Chang
- Department of Physics, School of Engineering and Applied Sciences, Harvard University, Cambridge, MA.,Department of Chemical and Biological Engineering, Montana State University, Bozeman, MT
| | - Joshua T Wolfe
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD
| | - Audrey E Fischer
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD
| | - Thomas S Mehoke
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD
| | - Huidan Zhang
- Department of Physics, School of Engineering and Applied Sciences, Harvard University, Cambridge, MA.,Key Laboratory of Cell Biology, Department of Cell Biology, Ministry of Public Health, China Medical University, Shenyang, China.,Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, Shenyang, China
| | - Ye Tao
- Department of Physics, School of Engineering and Applied Sciences, Harvard University, Cambridge, MA
| | - W Lloyd Ung
- Department of Physics, School of Engineering and Applied Sciences, Harvard University, Cambridge, MA
| | - Jeong-Mo Choi
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA
| | - João V Rodrigues
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA
| | - Abimbola O Kolawole
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI
| | - Stephan A Koehler
- Department of Physics, School of Engineering and Applied Sciences, Harvard University, Cambridge, MA
| | - Susan Wu
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD
| | - Peter M Thielen
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD
| | - Naiwen Cui
- Department of Physics, School of Engineering and Applied Sciences, Harvard University, Cambridge, MA
| | - Plamen A Demirev
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD
| | | | - Timothy R Julian
- Environmental Health Sciences and the Hopkins Water Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD.,Department of Environmental Microbiology, Swiss Federal Institute of Aquatic Science and Technology (Eawag), Dübendorf, Switzerland
| | - Kellogg Schwab
- Environmental Health Sciences and the Hopkins Water Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD
| | - Jeffrey S Lin
- Applied Physics Laboratory, Johns Hopkins University, Laurel, MD
| | - Thomas J Smith
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, Galveston, TX
| | - James M Pipas
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA
| | - Christiane E Wobus
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI
| | - Andrew B Feldman
- Department of Emergency Medicine, Johns Hopkins Medicine, Baltimore, MD
| | - David A Weitz
- Department of Physics, School of Engineering and Applied Sciences, Harvard University, Cambridge, MA
| | | |
Collapse
|
16
|
Abstract
OBJECTIVES Knee pain is one of the most common symptoms of knee osteoarthritis (OA) that affects the quality of life in the older adults, and identifying the contributing factors of knee pain is important. We hypothesized that higher fruit and vegetable consumption might be associated with the severity of knee pain lower prevalence of severe knee pain by affecting pain perception in the knee joint. Therefore, we investigated the relationship between self-reported knee pain and the consumption of fruits vegetables, carotenoids and vitamin C and self-reported knee pain. DESIGN Nationally representative cross sectional study. SETTING 2010-2011 rounds of the Korean National Health and Nutrition Examination Survey. PARTICIPANTS A total of 6588 subjects aged ≥50 years were participated. METHODS Severity of knee pain was estimated using a 10-point numeric rating scale (NRS). Daily intake of fruits, vegetables, and vitamins were estimated using data from 24-hour recalls and food frequency questionnaires. RESULTS The NRS scores of knee pain decreased significantly with increasing fruit and vegetable intake quartiles. A multivariate logistic regression analysis showed that the fourth quartile of vegetable and fruit consumption was associated with decreased prevalence of severe knee pain (OR 0.59, 95% CI 0.48-0.73) compared with first quartile of vegetable and fruit consumption; however, carotenoids and vitamin C consumption was not associated with the severity of knee pain. CONCLUSIONS In conclusion, severe knee pain was independently associated with fruit and vegetable consumption. Our findings suggest that intake of whole fruits and vegetables may help improve knee pain in older adults.
Collapse
Affiliation(s)
- H S Han
- Jee-Yon Lee, M.D. Department of Family Medicine, CHA University College of Medicine, CHA Bundang Medical Center, Chaum Life Center, 335 Pangyo-ro, Bundang-gu, Sungnam-si, Republic of Korea, Tel.: 82-31-881-7596, FAX: 82-2-362-2473, E-mail address:
| | | | | | | |
Collapse
|
17
|
Tao Y, Rotem A, Zhang H, Chang CB, Basu A, Kolawole AO, Koehler SA, Ren Y, Lin JS, Pipas JM, Feldman AB, Wobus CE, Weitz DA. Rapid, targeted and culture-free viral infectivity assay in drop-based microfluidics. Lab Chip 2015; 15:3934-40. [PMID: 26304791 DOI: 10.1039/c5lc00556f] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
A key viral property is infectivity, and its accurate measurement is crucial for the understanding of viral evolution, disease and treatment. Currently viral infectivity is measured using plaque assays, which involve prolonged culturing of host cells, and whose measurement is unable to differentiate between specific strains and is prone to low number fluctuation. We developed a rapid, targeted and culture-free infectivity assay using high-throughput drop-based microfluidics. Single infectious viruses are incubated in a large number of picoliter drops with host cells for one viral replication cycle followed by in-drop gene-specific amplification to detect infection events. Using murine noroviruses (MNV) as a model system, we measure their infectivity and determine the efficacy of a neutralizing antibody for different variants of MNV. Our results are comparable to traditional plaque-based assays and plaque reduction neutralization tests. However, the fast, low-cost, highly accurate genomic-based assay promises to be a superior method for drug screening and isolation of resistant viral strains. Moreover our technique can be adapted to measuring the infectivity of other pathogens, such as bacteria and fungi.
Collapse
Affiliation(s)
- Ye Tao
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Tao Y, Rotem A, Zhang H, Cockrell SK, Koehler SA, Chang CB, Ung LW, Cantalupo PG, Ren Y, Lin JS, Feldman AB, Wobus CE, Pipas JM, Weitz DA. Inside Back Cover: Artifact-Free Quantification and Sequencing of Rare Recombinant Viruses by Using Drop-Based Microfluidics (ChemBioChem 15/2015). Chembiochem 2015. [DOI: 10.1002/cbic.201500460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Ye Tao
- School of Engineering and Applied Sciences; Harvard University; 29 Oxford Street Pierce 231 Cambridge MA 02138 USA
- School of Mechatronics Engineering; Harbin Institute of Technology; 92 West Dazhi Street Nan Gang District Harbin 150001 China
| | - Assaf Rotem
- School of Engineering and Applied Sciences; Harvard University; 29 Oxford Street Pierce 231 Cambridge MA 02138 USA
| | - Huidan Zhang
- School of Engineering and Applied Sciences; Harvard University; 29 Oxford Street Pierce 231 Cambridge MA 02138 USA
- Department of Cell Biology; Key Laboratory of Cell Biology; Ministry of Public Health; Key Laboratory of Medical Cell Biology; Ministry of Education; China Medical University; 92 Beier Road Heping District Shenyang 110001 China
| | - Shelley K. Cockrell
- Department of Biological Sciences; University of Pittsburgh; 4249 Fifth Avenue Pittsburgh PA 15260 USA
| | - Stephan A. Koehler
- School of Engineering and Applied Sciences; Harvard University; 29 Oxford Street Pierce 231 Cambridge MA 02138 USA
| | - Connie B. Chang
- School of Engineering and Applied Sciences; Harvard University; 29 Oxford Street Pierce 231 Cambridge MA 02138 USA
- Chemical and Biological Engineering Department; Montana State University; Bozeman MT 59717 USA
| | - Lloyd W. Ung
- School of Engineering and Applied Sciences; Harvard University; 29 Oxford Street Pierce 231 Cambridge MA 02138 USA
| | - Paul G. Cantalupo
- Department of Biological Sciences; University of Pittsburgh; 4249 Fifth Avenue Pittsburgh PA 15260 USA
| | - Yukun Ren
- School of Mechatronics Engineering; Harbin Institute of Technology; 92 West Dazhi Street Nan Gang District Harbin 150001 China
| | - Jeffrey S. Lin
- Applied Physics Laboratory; Johns Hopkins University; 11100 Johns Hopkins Road Laurel MD 20723 USA
| | - Andrew B. Feldman
- Applied Physics Laboratory; Johns Hopkins University; 11100 Johns Hopkins Road Laurel MD 20723 USA
- Department of Emergency Medicine; Johns Hopkins Medicine; 5801 Smith Avenue Suite 3220 Baltimore MD 21209 USA
| | - Christiane E. Wobus
- Department of Microbiology and Immunology; University of Michigan; 1150 West Medical Center Drive 5622 Medical Science II Ann Arbor MI 48109 USA
| | - James M. Pipas
- Department of Biological Sciences; University of Pittsburgh; 4249 Fifth Avenue Pittsburgh PA 15260 USA
| | - David A. Weitz
- School of Engineering and Applied Sciences; Harvard University; 29 Oxford Street Pierce 231 Cambridge MA 02138 USA
- Department of Physics; Harvard University; 29 Oxford Street Pierce 231 Cambridge MA 02138 USA
| |
Collapse
|
19
|
Tao Y, Rotem A, Zhang H, Cockrell SK, Koehler SA, Chang CB, Ung LW, Cantalupo PG, Ren Y, Lin JS, Feldman AB, Wobus CE, Pipas JM, Weitz DA. Artifact-Free Quantification and Sequencing of Rare Recombinant Viruses by Using Drop-Based Microfluidics. Chembiochem 2015; 16:2167-71. [PMID: 26247541 DOI: 10.1002/cbic.201500384] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [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: 07/27/2015] [Indexed: 01/23/2023]
Abstract
Recombination is an important driver in the evolution of viruses and thus is key to understanding viral epidemics and improving strategies to prevent future outbreaks. Characterization of rare recombinant subpopulations remains technically challenging because of artifacts such as artificial recombinants, known as chimeras, and amplification bias. To overcome this, we have developed a high-throughput microfluidic technique with a second verification step in order to amplify and sequence single recombinant viruses with high fidelity in picoliter drops. We obtained the first artifact-free estimate of in vitro recombination rate between murine norovirus strains MNV-1 and WU20 co-infecting a cell (P(rec) = 3.3 × 10(-4) ± 2 × 10(-5) ) for a 1205 nt region. Our approach represents a time- and cost-effective improvement over current methods, and can be adapted for genomic studies requiring artifact- and bias-free selective amplification, such as microbial pathogens, or rare cancer cells.
Collapse
Affiliation(s)
- Ye Tao
- School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Pierce 231, Cambridge, MA, 02138, USA.,School of Mechatronics Engineering, Harbin Institute of Technology, 92 West Dazhi Street, Nan Gang District, Harbin, 150001, China
| | - Assaf Rotem
- School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Pierce 231, Cambridge, MA, 02138, USA
| | - Huidan Zhang
- School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Pierce 231, Cambridge, MA, 02138, USA.,Department of Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, 92 Beier Road, Heping District, Shenyang, 110001, China
| | - Shelley K Cockrell
- Department of Biological Sciences, University of Pittsburgh, 4249 Fifth Avenue, Pittsburgh, PA, 15260, USA
| | - Stephan A Koehler
- School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Pierce 231, Cambridge, MA, 02138, USA
| | - Connie B Chang
- School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Pierce 231, Cambridge, MA, 02138, USA.,Chemical and Biological Engineering Department, Montana State University, Bozeman, MT, 59717, USA
| | - Lloyd W Ung
- School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Pierce 231, Cambridge, MA, 02138, USA
| | - Paul G Cantalupo
- Department of Biological Sciences, University of Pittsburgh, 4249 Fifth Avenue, Pittsburgh, PA, 15260, USA
| | - Yukun Ren
- School of Mechatronics Engineering, Harbin Institute of Technology, 92 West Dazhi Street, Nan Gang District, Harbin, 150001, China
| | - Jeffrey S Lin
- Applied Physics Laboratory, Johns Hopkins University, 11100 Johns Hopkins Road, Laurel, MD, 20723, USA
| | - Andrew B Feldman
- Applied Physics Laboratory, Johns Hopkins University, 11100 Johns Hopkins Road, Laurel, MD, 20723, USA.,Department of Emergency Medicine, Johns Hopkins Medicine, 5801 Smith Avenue, Suite 3220, Baltimore, MD, 21209, USA
| | - Christiane E Wobus
- Department of Microbiology and Immunology, University of Michigan, 1150 West Medical Center Drive, 5622 Medical Science II, Ann Arbor, MI, 48109, USA
| | - James M Pipas
- Department of Biological Sciences, University of Pittsburgh, 4249 Fifth Avenue, Pittsburgh, PA, 15260, USA
| | - David A Weitz
- School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Pierce 231, Cambridge, MA, 02138, USA. .,Department of Physics, Harvard University, 29 Oxford Street, Pierce 231, Cambridge, MA, 02138, USA.
| |
Collapse
|
20
|
Chang CB, Wilking JN, Kim SH, Shum HC, Weitz DA. Monodisperse Emulsion Drop Microenvironments for Bacterial Biofilm Growth. Small 2015; 11:3954-61. [PMID: 25959709 DOI: 10.1002/smll.201403125] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [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: 10/22/2014] [Revised: 03/13/2015] [Indexed: 05/20/2023]
Abstract
In this work, microfluidic technology is used to rapidly create hundreds of thousands of monodisperse double and triple emulsion drops that serve as 3D microenvironments for the containment and growth of bacterial biofilms. The size of these drops, with diameters from tens to hundreds of micrometers, makes them amenable to rapid manipulation and analysis. This is demonstrated by using microscopy to visualize cellular differentiation of Bacillus subtilis biofilm communities within each drop and the bacterial biofilm microstructure. Biofilm growth is explored upon specific interfaces in double and triple emulsions and upon negative and positive radii of curvature. Biofilm attachment of matrix and flagella mutants is studied as well as biofilms of Pseudomonas aeruginosa. This is the first demonstration of biofilms grown in microscale emulsion drops, which serve as both templates and containers for biofilm growth and attachment. These microenvironments have the potential to transform existing high-throughput screening methods for bacterial biofilms.
Collapse
Affiliation(s)
- Connie B Chang
- School of Engineering and Applied Science, Department of Physics Harvard University, Cambridge, MA, 02138, USA
- Chemical and Biological Engineering Department, Montana State University, Bozeman, MT, 59717, USA
| | - James N Wilking
- School of Engineering and Applied Science, Department of Physics Harvard University, Cambridge, MA, 02138, USA
- Chemical and Biological Engineering Department, Montana State University, Bozeman, MT, 59717, USA
| | - Shin-Hyun Kim
- School of Engineering and Applied Science, Department of Physics Harvard University, Cambridge, MA, 02138, USA
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, Daejeon, 305-701, Korea
| | - Ho Cheung Shum
- School of Engineering and Applied Science, Department of Physics Harvard University, Cambridge, MA, 02138, USA
- Department of Mechanical Engineering, The University of Hong Kong, China
| | - David A Weitz
- School of Engineering and Applied Science, Department of Physics Harvard University, Cambridge, MA, 02138, USA
| |
Collapse
|
21
|
Kang S, Park J, Kang SB, Chang CB. MRI findings of young male soldiers with atraumatic anterior knee pain. Scand J Med Sci Sports 2015; 26:572-8. [PMID: 25996828 DOI: 10.1111/sms.12486] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/29/2015] [Indexed: 12/11/2022]
Abstract
The purpose of this study is to investigate abnormal magnetic resonance image (MRI) findings of young active males with atraumatic anterior knee pain (AKP). Targeting young male soldiers, we prospectively gathered and analyzed 157 knee MRIs from patients with atraumatic AKP (AKP group) and 53 knee MRIs from patients without knee pain (control group). Abnormalities of the patellofemoral (PF) joint and extensor mechanism on MRI were more common in the AKP group than the control group (48% vs 13%, P < 0.001). The overall prevalence of medial plica (34% vs 13%, P = 0.004) and the prevalence of the thick medial plica (9% vs 0%, P = 0.023) were considerably higher in the AKP group. The cartilaginous sulcus angle in the AKP group without abnormalities on MRI was significantly higher than both the AKP group with abnormalities and the control group (145° vs 141° vs 142°, respectively, P = 0.001). Our results suggest that careful assessment of young, active males with atraumatic AKP is warranted regarding PF joint abnormalities, particularly the presence of medial plica and/or subtle abnormalities of the articular geometry. The results from the present study could be used for the management of patients with AKP.
Collapse
Affiliation(s)
- S Kang
- Department of Orthopaedic Surgery, Asan Medical Center Children's Hospital, University of Ulsan College of Medicine, Seoul, Korea.,Department of Orthopaedic Surgery, Aerospace Medical Center, Republic of Korea Air Force, Cheongwon-gun, Chungcheongbuk-do, Korea
| | - J Park
- Department of Nursing, Seoul National University Hospital, Seoul, Korea
| | - S-B Kang
- Department of Orthopaedic Surgery, Seoul National University Boramae Hospital, Seoul, Korea
| | - C B Chang
- Department of Orthopaedic Surgery, Seoul National University Boramae Hospital, Seoul, Korea
| |
Collapse
|
22
|
Lee KM, Chang CB, Park MS, Kang SB, Kim TK, Chung CY. Changes of knee joint and ankle joint orientations after high tibial osteotomy. Osteoarthritis Cartilage 2015; 23:232-8. [PMID: 25450843 DOI: 10.1016/j.joca.2014.11.001] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 10/04/2014] [Accepted: 11/02/2014] [Indexed: 02/06/2023]
Abstract
OBJECTIVE We sought to determine (1) whether change in the tibial plateau inclination (TPI) after high tibial osteotomy (HTO) is different from change in the knee joint line orientation (KJLO) relative to the ground; (2) whether, in varus knee OA patients before and after HTO, these radiographic measures are different from those in normal control; and (3) whether the postoperative values of the TPI and KJLO relative to the ground are associated with short term clinical outcome scores after HTO. DESIGN Fifty patients who underwent HTO and 75 normal controls were assessed with four radiographic measures. We compared the measures before HTO with those after HTO and with those of the normal controls, then examined associations between the postoperative radiographic measures and clinical outcome scores 1-year after HTO. RESULTS After HTO, TPI increased 9.0°, whereas KJLO relative to the ground only increased 4.1°, with a compensatory change of the ankle joint line orientation. However, the postoperative KJLO relative to the ground in the HTO group was significantly different from that of the normal controls (mean difference, 4.9°; P < 0.001). In the multiple regression analyses, the postoperative radiographic measures were not associated with outcome clinical scores 1 year after HTO. CONCLUSION After HTO the relative KJLO changed significantly less than did the anatomical geometry of the proximal tibia. Although the KJLO after the HTO was still significantly different from that of normal knees, its value did not adversely affect clinical outcome scores 1 year after HTO.
Collapse
Affiliation(s)
- K M Lee
- Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam-si, South Korea
| | - C B Chang
- Department of Orthopaedic Surgery, SMG-SNU Boramae Medical Center, Seoul, South Korea; Department of Orthopaedic Surgery, Seoul National University College of Medicine, South Korea.
| | - M S Park
- Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam-si, South Korea
| | - S-B Kang
- Department of Orthopaedic Surgery, SMG-SNU Boramae Medical Center, Seoul, South Korea; Department of Orthopaedic Surgery, Seoul National University College of Medicine, South Korea
| | - T K Kim
- Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam-si, South Korea; Department of Orthopaedic Surgery, Seoul National University College of Medicine, South Korea
| | - C Y Chung
- Department of Orthopaedic Surgery, Seoul National University Bundang Hospital, Seongnam-si, South Korea; Department of Orthopaedic Surgery, Seoul National University College of Medicine, South Korea
| |
Collapse
|
23
|
Fischer AE, Wu SK, Proescher JBG, Rotem A, Chang CB, Zhang H, Tao Y, Mehoke TS, Thielen PM, Kolawole AO, Smith TJ, Wobus CE, Weitz DA, Lin JS, Feldman AB, Wolfe JT. A high-throughput drop microfluidic system for virus culture and analysis. J Virol Methods 2014; 213:111-7. [PMID: 25522923 DOI: 10.1016/j.jviromet.2014.12.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [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: 08/21/2014] [Revised: 12/04/2014] [Accepted: 12/05/2014] [Indexed: 02/05/2023]
Abstract
High mutation rates and short replication times lead to rapid evolution in RNA viruses. New tools for high-throughput culture and analysis of viral phenotypes will enable more effective studies of viral evolutionary processes. A water-in-oil drop microfluidic system to study virus-cell interactions at the single event level on a massively parallel scale is described here. Murine norovirus (MNV-1) particles were co-encapsulated with individual RAW 264.7 cells in 65 pL aqueous drops formed by flow focusing in 50 μm microchannels. At low multiplicity of infection (MOI), viral titers increased greatly, reaching a maximum 18 h post-encapsulation. This system was employed to evaluate MNV-1 escape from a neutralizing monoclonal antibody (clone A6.2). Further, the system was validated as a means for testing escape from antibody neutralization using a series of viral point mutants. Finally, the replicative capacity of single viral particles in drops under antibody stress was tested. Under standard conditions, many RNA virus stocks harbor minority populations of genotypic and phenotypic variants, resulting in quasispecies. These data show that when single cells are encapsulated with single viral particles under antibody stress without competition from other virions, the number of resulting infectious particles is nearly equivalent to the number of viral genomes present. These findings suggest that lower fitness virions can infect cells successfully and replicate, indicating that the microfluidics system may serve as an effective tool for isolating mutants that escape evolutionary stressors.
Collapse
Affiliation(s)
- Audrey E Fischer
- The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
| | - Susan K Wu
- The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
| | - Jody B G Proescher
- The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
| | - Assaf Rotem
- Harvard School of Engineering and Applied Sciences, 9 Oxford Street, Cambridge, MA 02138, USA
| | - Connie B Chang
- Harvard School of Engineering and Applied Sciences, 9 Oxford Street, Cambridge, MA 02138, USA
| | - Huidan Zhang
- Harvard School of Engineering and Applied Sciences, 9 Oxford Street, Cambridge, MA 02138, USA
| | - Ye Tao
- Harvard School of Engineering and Applied Sciences, 9 Oxford Street, Cambridge, MA 02138, USA
| | - Thomas S Mehoke
- The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
| | - Peter M Thielen
- The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
| | - Abimbola O Kolawole
- Department of Microbiology and Immunology, University of Michigan Medical School, 1150 West Medical Center Drive, Ann Arbor, MI 48109, USA
| | - Thomas J Smith
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch at Galveston, 301 University Boulevard, Galveston, TX 77555, USA
| | - Christiane E Wobus
- Department of Microbiology and Immunology, University of Michigan Medical School, 1150 West Medical Center Drive, Ann Arbor, MI 48109, USA
| | - David A Weitz
- Harvard School of Engineering and Applied Sciences, 9 Oxford Street, Cambridge, MA 02138, USA
| | - Jeffrey S Lin
- The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
| | - Andrew B Feldman
- The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA
| | - Joshua T Wolfe
- The Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, USA.
| |
Collapse
|
24
|
Chang CB, Han SA, Kim EM, Lee S, Seong SC, Lee MC. Chondrogenic potentials of human synovium-derived cells sorted by specific surface markers. Osteoarthritis Cartilage 2013; 21:190-9. [PMID: 23069852 DOI: 10.1016/j.joca.2012.10.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 09/25/2012] [Accepted: 10/04/2012] [Indexed: 02/02/2023]
Abstract
OBJECTIVE We aimed to evaluate expression levels of nine candidate surface markers for chondrogenic potential in human synovial cells and to determine whether cell pellets positively sorted by each specific marker would have valuable chondrogenic potential. METHODS The expression levels of the selected nine leading surface markers in synovial cells from knee joints in 15 patients with primary knee osteoarthritis were evaluated at the stage of isolation and after cultivation using flow cytometry. We obtained positive and negative cells for each surface marker using a magnetically activated cell sorting method and compared chondrogenic potentials between the positive and the negative cell pellets. RESULTS CD29, CD44, CD73, and CD90 were expressed on the most synovial cells at the isolation stage and on almost all cells at stage of P0 and P1. CD133 was rarely expressed at any stages of the evaluated cells. CD166 was expressed in 7.1% of cells at the isolation stage on average, but this expression increased after cell passages. The expressions of CD10 and CD105 also increased after cell passages while the expression of CD49a made no significant difference at progressive stages of isolation and passage. Comparison of chondrogenic potentials between positive and negative cell pellets for each marker revealed that only CD105- and CD166-positive cell pellets showed better chondrogenic potentials (type II collagen gene expression, cartilage matrix formation, and GAG expression) than the corresponding negative cell pellets. CONCLUSION Our study suggests that CD105 and CD166 would be valuable surface markers associated with chondrogenic potential; thus, CD105- and CD166-enriched cells derived from human synovium would be practical and valuable sources for cartilage regeneration.
Collapse
Affiliation(s)
- C B Chang
- Department of Orthopaedic Surgery, Seoul National University College of Medicine, Seoul, South Korea
| | | | | | | | | | | |
Collapse
|
25
|
Abstract
The structural evolution and rheology of dense nanoemulsion gels, which have been formed by creating strong attractions between slippery nanodroplets, are explored as a function of steady shear rate using rheological small-angle neutron scattering (rheo-SANS). For applied stresses above the yield stress of the gel, the network yields, fracturing into aggregates that break and reform as they tumble and interact in the shear flow. The average aggregate size decreases with increasing shear rate; meanwhile, droplet rearrangements within the clusters, allowed by the slippery nature of the attractive interaction, increase the local density within the aggregates. At the highest shear rates, all clusters disaggregate completely into individual droplets.
Collapse
Affiliation(s)
- James N Wilking
- Department of Chemistry and Biochemistry, University of California-Los Angeles, 607 Charles E. Young Drive East, Los Angeles, California 90095, United States
| | | | | | | | | |
Collapse
|
26
|
Chang CB, Choi JY, Koh IJ, Seo ES, Seong SC, Kim TK. What should be considered in using standard knee radiographs to estimate mechanical alignment of the knee? Osteoarthritis Cartilage 2010; 18:530-8. [PMID: 20060951 DOI: 10.1016/j.joca.2009.12.004] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Revised: 11/17/2009] [Accepted: 12/01/2009] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Anatomical tibiofemoral angle (anatomical TFA) of the knee measured on standard knee radiographs is still widely used as proxy for mechanical tibiofemoral angle (mechanical TFA), because of the practical and economic limitations in using full-limb radiographs. However, reported differences between anatomical and mechanical TFAs show wide variations. The first aim of this study was to determine whether gender, the presence of advanced osteoarthritis (OA), and history of total knee arthroplasty (TKA) influence the differences between anatomical and mechanical TFAs. The second aim was to identify anatomical features that cause divergences between anatomical and mechanical TFAs, and the final aim was to determine whether anatomical TFA measured using reference points more distant from the knee provides more accurate estimates of mechanical TFA. DESIGN In 102 knees with advanced OA before and after TKAs and 99 control knees with no/minimal OA, we assessed the differences between two anatomical TFAs, namely, anatomical TFA1 and anatomical TFA2, which were based on conventional or more distant proximal and distal reference points on standard knee radiographs, respectively, and the mechanical TFA measured on full-limb radiographs. These differences were investigated for women vs men, no/minimal OA vs advanced OA, and for knees before vs after TKA. Regression analyses were performed to determine associations between femoral and tibial anatomical characteristics and the differences between mechanical and anatomical TFAs. RESULTS The OA group showed significantly greater differences between mechanical and anatomical TFAs than the control group for both genders. In OA and TKA group, women were more likely to have greater mean differences between mechanical and anatomical TFAs than men. However, TKA did not significantly affect these differences. Femoral and tibial bowing angles, particularly of the femur, were found to be the major contributors to divergences between mechanical and two anatomical TFAs. Furthermore, anatomical TFA2 was found to provide more accurate estimates of mechanical TFA. CONCLUSIONS We found that the differences between mechanical and anatomical TFAs depend on gender and the presence of advanced OA, but not on a history of TKA. These findings indicate that prediction of mechanical TFA based on anatomical TFA is dependent on study population characteristics. This study also shows that the presence of lateral bowing of the femur is a major cause of mechanical TFA to anatomical TFA variations associated with gender and advanced OA. To reduce the adverse effects of anatomical variations on estimations of mechanical TFA based on an anatomical TFA method, more distant proximal and distal reference points are recommended to determine anatomical TFA value on standard knee radiographs.
Collapse
Affiliation(s)
- C B Chang
- Joint Reconstruction Center, Seoul National University Bundang Hospital, Seongnamsi, South Korea
| | | | | | | | | | | |
Collapse
|
27
|
Chang CB, Seong SC, Kim TK. Evaluations of radiographic joint space--do they adequately predict cartilage conditions in the patellofemoral joint of the patients undergoing total knee arthroplasty for advanced knee osteoarthritis? Osteoarthritis Cartilage 2008; 16:1160-6. [PMID: 18387318 DOI: 10.1016/j.joca.2008.02.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2007] [Accepted: 02/17/2008] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine whether assessments of patellofemoral (PF) joint space reliably predict the cartilage conditions in the PF joint of the patients undergoing total knee arthroplasty (TKA) for advanced knee osteoarthritis. METHODS Radiographic joint spaces and gross cartilage conditions in the PF joint were assessed in 151 osteoarthritic knees undergoing TKA. Minimum joint space widths (MJSWs) in the medial and lateral compartments of the PF joint were measured separately on Merchant radiographs. Degrees of joint space were graded as normal, narrowed and obliterated, and expected locations of significant cartilage lesions were classified as medial, lateral, and global. Cartilage lesions were grossly assessed in terms of their severity (depth and size) and location. Cross-table analyses and kappa statistics were used to determine the level of agreements between radiographic and gross assessments and the diagnostic accuracies of the radiographic assessments. RESULTS The agreements between the radiographic assessments and the gross assessments on the lesion severities and locations were only fair [kappa coefficient (k)=0.288 and 0.211, respectively]. The cross-table analyses demonstrated that 45 (47.4%) of 95 knees with a normal radiographic joint space had moderate or severe cartilage degeneration of the PF joint identified with gross assessments. In the radiographic assessments, the lateral compartment of the PF joint was the most frequent location of joint space narrowing (71.4%) whereas in the gross assessments, the medial compartment of the PF joint was the most frequent location of significant cartilage lesion (48.1%). Diagnostic accuracies on the lesion severities and locations were generally poor. CONCLUSION This study demonstrates that prediction of the cartilage conditions of the PF joint by the radiographic joint space can be inaccurate.
Collapse
Affiliation(s)
- C B Chang
- Joint Reconstruction Center, Seoul National University Bundang Hospital, Seongnamsi, Republic of Korea
| | | | | |
Collapse
|
28
|
Yoo JH, Kang YG, Chang CB, Seong SC, Kim TK. The relationship of the medially-offset stem of the tibial component to the medial tibial cortex in total knee replacements in Korean patients. ACTA ACUST UNITED AC 2008; 90:31-6. [PMID: 18160496 DOI: 10.1302/0301-620x.90b1.19605] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We examined the placement of the stem in relation to the medial tibial cortex when using total knee replacements (TKRs) with medially-offset tibial stems in Korean patients. Measurements were performed on the pre- and post-operative radiographs of 246 osteoarthritic knees replaced between January 2005 and May 2006 using the Genesis II or E-motion TKR with a medially-offset stem. Pre-operatively, we measured the distance between the mechanical axis and that of the tibial shaft and post-operatively, that between the midline of the tibial stem and the axis of the shaft. Knees were identified in which there was radiological contact between the tip of the stem and the medial tibial cortex. The mechanical axis was located medial to the axis of the shaft in 203 knees (82.5%). Post-operatively, the midline of the tibial stem was located medial to the tibial shaft axis in 196 knees (79.7%). In 16 knees (6.5%) there was radiological contact between the tibial stem or cement mantle and the medial tibial cortex. Our study has shown that the medially-offset stem in the tibial component may not be a good option for knees undergoing replacement for advanced osteoarthritis in some Korean patients.
Collapse
Affiliation(s)
- J H Yoo
- Department of Orthopaedic Surgery, National Police Hospital, 58 Garak-dong Street, Songpa-gu, Seoul 138-708, Korea
| | | | | | | | | |
Collapse
|
29
|
Chang CB, Knobler CM, Gelbart WM, Mason TG. Curvature dependence of viral protein structures on encapsidated nanoemulsion droplets. ACS Nano 2008; 2:281-6. [PMID: 19206628 DOI: 10.1021/nn700385z] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Virus-like particles are biomimetic delivery vehicles that cloak nanoscale cores inside coatings of viral capsid proteins, offering the potential for protecting their contents and targeting them to particular tissues and cells. To date, encapsidation has been demonstrated only for a relatively limited variety of core materials, such as compressible polymers and facetted nanocrystals, over a narrow range of cores sizes and of pH and ionic strength. Here, we encapsidate spherical nanodroplets of incompressible oil stabilized by adsorbed anionic surfactant using cationic capsid protein purified from cowpea chlorotic mottle virus. By imaging with transmission electron microscopy we show that, as the droplets become larger than the wild-type RNA core, the protein is forced to self-assemble into spherical shells that are not perfect icosahedra having special triangulation numbers characteristic of the Caspar-Klug hierarchy. Consequently, the distribution of protein conformations on larger droplets is significantly different than in the wild-type shell.
Collapse
Affiliation(s)
- Connie B Chang
- Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, California 90095, USA
| | | | | | | |
Collapse
|
30
|
Park KK, Chang CB, Kang YG, Seong SC, Kim TK. Correlation of maximum flexion with clinical outcome after total knee replacement in Asian patients. ACTA ACUST UNITED AC 2007; 89:604-8. [PMID: 17540744 DOI: 10.1302/0301-620x.89b5.18117] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
This study aimed to determine the correlation between the amount of maximum flexion and the clinical outcome in 207 Koreans (333 knees) undergoing total knee replacement. The association of maximum flexion with clinical outcome was evaluated one year postoperatively using three scoring systems; the American Knee Society score, Western Ontario McMaster Universities Osteoarthritis index and the Short Form-36. The mean maximum flexion decreased post-operatively at 12 months from 140.1 degrees (60 degrees to 160 degrees ) to 133.0 degrees (105 degrees to 150 degrees ). Only the social function score of the Short Form-36 correlated significantly with maximum flexion (correlation coefficient = 0.180, p = 0.039). In comparative analyses of subgroups divided by a maximum flexion of 120 degrees , we found no significant differences in any parameters except the social function score of the Short Form-36 (41.9 vs 47.3, p = 0.031). Knees with a maximum flexion of more than 135 degrees had a better functional Western Ontario McMasters Universities Osteoarthritis index score than knees with maximum flexion of 135 degrees or less (17.5 vs 14.3, p = 0.031). We found only weak correlation between the postoperative maximum flexion and the clinical parameters for pain relief, function and quality of life, even in Korean patients. Efforts to increase post-operative maximum flexion should be exercised with caution until concerns relating to high-flexion activities are sufficiently resolved.
Collapse
Affiliation(s)
- K K Park
- Joint Reconstruction Center, Seoul National University, Bundang Hospital, 300 Gumi-dong, Bundang-gu, Seongnam-si, Gyeonggi-do (463-707), Seoul, Korea
| | | | | | | | | |
Collapse
|
31
|
Wilking JN, Graves SM, Chang CB, Meleson K, Lin MY, Mason TG. Dense cluster formation during aggregation and gelation of attractive slippery nanoemulsion droplets. Phys Rev Lett 2006; 96:015501. [PMID: 16486472 DOI: 10.1103/physrevlett.96.015501] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2005] [Indexed: 05/06/2023]
Abstract
Using time-resolved small angle neutron scattering, we have measured the wave-number-dependent structure factor S(q) of monodisperse nanoemulsions that aggregate and gel after we suddenly turn on a strong, short-range, slippery attraction between the droplets. At high q, peaks in S(q) appear as dense clusters of droplets form, and S(q) increases strongly toward low q, as these dense clusters become locked into a rigid gel network, despite the fluidity of the films between the droplets. The long-time high-q structure of nanoemulsion gels formed by slippery diffusion-limited cluster aggregation is universal in shape and remarkably independent of the droplet volume fraction, phi.
Collapse
Affiliation(s)
- J N Wilking
- Department of Chemistry and Biochemistry, California NanoSystems Institute, University of California-Los Angeles, Los Angeles, California 90095, USA
| | | | | | | | | | | |
Collapse
|
32
|
Han I, Chang CB, Lee S, Lee MC, Seong SC, Kim TK. Correlation of the condition of the patellar articular cartilage and patellofemoral symptoms and function in osteoarthritic patients undergoing total knee arthroplasty. ACTA ACUST UNITED AC 2005; 87:1081-4. [PMID: 16049243 DOI: 10.1302/0301-620x.87b8.16209] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We sought to determine the degree of correlation between the condition of the patellar articular cartilage and patellofemoral symptoms and function in osteoarthritic patients undergoing total knee arthroplasty. The depth of the osteoarthritic lesion, as graded by the Outerbridge classification and its size and location were assessed to determine the condition of the patellar cartilage in 80 consecutive osteoarthritic knees undergoing total knee arthroplasty. The association between the condition of the cartilage and patellofemoral symptoms and function was investigated by correlation analysis. The depth and size of the lesion had a significant but weak correlation with anterior knee pain (r = -0.300 and -0.289; p = 0.007 and 0.009, respectively), whereas location had no significant association (p > 0.05). None had a significant association with patellofemoral functional parameters (chair-rising, stair-climbing, and quadriceps power) (p > 0.05). Our study indicates that patellofemoral symptoms and function are not completely determined by the condition of the cartilage. Caution should be taken when the symptoms and functional limitations are attributed to a lesion in the patellofemoral joint in making a decision regarding patellar resurfacing in total knee arthroplasty.
Collapse
Affiliation(s)
- I Han
- Joint Reconstruction Centre, Seoul National University Bundang Hospital, 300 Gumidong, Seongnamsi, Gyunggido, Korea
| | | | | | | | | | | |
Collapse
|
33
|
Huang CC, Chang CB, Liu JY, Basavappa S, Lim PH. Effects of calcium, calmodulin, protein kinase C and protein tyrosine kinases on volume-activated taurine efflux in human erythroleukemia cells. J Cell Physiol 2001; 189:316-22. [PMID: 11748589 DOI: 10.1002/jcp.10027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The effects of calcium, calmodulin, protein kinase C (PKC) and protein tyrosine kinase (PTK) modulators were examined on the volume-activated taurine efflux in the erythroleukemia cell line K562. Exposure to hypoosmotic solution significantly increased taurine efflux and intracellular calcium concentration ([Ca2+]i). The Ca2+ channel blockers La3+ (1 mM), verapamil (200 microM) and nifedipine (100 microM) inhibited the hypoosmotically-induced [Ca2+]i increase by more than 90%, while the volume-activated taurine efflux was inhibited by 61.3 +/- 9.5, 74.1 +/- 9.3 and 38.0 +/- 1.5%, respectively. Furthermore, the calmodulin inhibitors W7 (50 microM) and trifluoperazine (10 microM) and the Ca2+/calmodulin-dependent protein kinase II inhibitor KN-62 (2 microM) significantly blocked the volume-activated taurine efflux by 93.4 +/- 2.7, 77.9 +/- 3.5 and 61.3 +/- 15.8%, respectively. In contrast, the PKC inhibitor staurosporine (200 nM) or the PKC activator phorbol 12-myristate 13-acetate (100 nM) did not have significant effects on the volume-activated taurine efflux. However, pretreatment with PTK inhibitors genistein, tyrphostin A25, and tyrphostin A47 blocked the volume-activated taurine efflux. These results suggest that the volume-activated taurine efflux in K562 cells may not directly involve Ca2+, but may require the presence of calmodulin and/or PTK.
Collapse
Affiliation(s)
- C C Huang
- Department of Physiology, Chung Shan Medical and Dental College, Taichung, Taiwan ROC.
| | | | | | | | | |
Collapse
|