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Vaidya SR. Immuno-Colorimetric Neutralization Test: A Surrogate for Widely Used Plaque Reduction Neutralization Tests in Public Health Virology. Viruses 2023; 15:v15040939. [PMID: 37112919 PMCID: PMC10143445 DOI: 10.3390/v15040939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/23/2023] [Accepted: 03/30/2023] [Indexed: 04/29/2023] Open
Abstract
Since their first documentation in 1952, plaque reduction neutralization tests (PRNTs) have become the choice of test for the measurement of neutralizing antibodies against a particular virus. However, PRNTs can be performed only against viruses that cause cytopathic effects (CPE). PRNTs also require skilled personnel and can be time-consuming depending on the time required for the virus to cause CPE. Hence, their application limits large-scale studies or epidemiological and laboratory investigations. Since 1978, many surrogate PRNTs or immunocolorimetric assay (ICA)-based focus reduction neutralization tests (FRNT) have been developed. In this article, ICAs and their utility in FRNTs for the characterization of neutralizing antibodies, homologous or heterologous cross-neutralization, and laboratory diagnosis of viruses of public health importance have been discussed. Additionally, possible advancements and automations have been described that may help in the development and validation of novel surrogate tests for emerging viruses.
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Affiliation(s)
- Sunil R Vaidya
- Virus Registry and Virus Repository, ICMR-National Institute of Virology, 20-A Dr. Ambedkar Road, Pune 411001, India
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2
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Mantri CK, Soundarajan G, Saron WAA, Rathore APS, Alonso S, St. John AL. Maternal Immunity and Vaccination Influence Disease Severity in Progeny in a Novel Mast Cell-Deficient Mouse Model of Severe Dengue. Viruses 2021; 13:v13050900. [PMID: 34066286 PMCID: PMC8152039 DOI: 10.3390/v13050900] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 05/07/2021] [Accepted: 05/11/2021] [Indexed: 12/25/2022] Open
Abstract
Sub-neutralizing concentrations of antibodies in dengue infected patients is a major risk factor for the development of dengue hemorrhagic fever and dengue shock syndrome. Here, we describe a mouse model with a deficiency in mast cells (MCs) in addition to a deficiency in Type-I and II IFN receptors for studying dengue virus (DENV) infection. We used this model to understand the influence of MCs in a maternal antibody-dependent model of severe dengue, where offspring born to DENV-immune mothers are challenged with a heterologous DENV serotype. Mice lacking both MCs and IFN receptors were found susceptible to primary DENV infection and showed morbidity and mortality. When these mice were immunized, pups born to DENV-immune mothers were found to be protected for a longer duration from a heterologous DENV challenge. In the absence of MCs and type-I interferon signaling, IFN-γ was found to protect pups born to naïve mothers but had the opposite effect on pups born to DENV-immune mothers. Our results highlight the complex interactions between MCs and IFN-signaling in influencing the role of maternal antibodies in DENV-induced disease severity.
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Affiliation(s)
- Chinmay Kumar Mantri
- Program in Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore 169857, Singapore; (G.S.); (W.A.A.S.)
- Correspondence: (C.K.M.); (A.L.S.J.)
| | - Gayathri Soundarajan
- Program in Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore 169857, Singapore; (G.S.); (W.A.A.S.)
| | - Wilfried A. A. Saron
- Program in Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore 169857, Singapore; (G.S.); (W.A.A.S.)
| | - Abhay P. S. Rathore
- Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA;
| | - Sylvie Alonso
- Infectious Diseases Translational Research Programme, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545, Singapore;
- Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore 119077, Singapore
| | - Ashley L. St. John
- Program in Emerging Infectious Diseases, Duke–National University of Singapore Medical School, Singapore 169857, Singapore; (G.S.); (W.A.A.S.)
- Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA;
- Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore 119077, Singapore
- SingHealth Duke-National University of Singapore Global Health Institute, Singapore 168753, Singapore
- Correspondence: (C.K.M.); (A.L.S.J.)
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3
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Lee CQE, Kerouanton B, Chothani S, Zhang S, Chen Y, Mantri CK, Hock DH, Lim R, Nadkarni R, Huynh VT, Lim D, Chew WL, Zhong FL, Stroud DA, Schafer S, Tergaonkar V, St John AL, Rackham OJL, Ho L. Coding and non-coding roles of MOCCI (C15ORF48) coordinate to regulate host inflammation and immunity. Nat Commun 2021; 12:2130. [PMID: 33837217 PMCID: PMC8035321 DOI: 10.1038/s41467-021-22397-5] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Accepted: 03/10/2021] [Indexed: 02/01/2023] Open
Abstract
Mito-SEPs are small open reading frame-encoded peptides that localize to the mitochondria to regulate metabolism. Motivated by an intriguing negative association between mito-SEPs and inflammation, here we screen for mito-SEPs that modify inflammatory outcomes and report a mito-SEP named "Modulator of cytochrome C oxidase during Inflammation" (MOCCI) that is upregulated during inflammation and infection to promote host-protective resolution. MOCCI, a paralog of the NDUFA4 subunit of cytochrome C oxidase (Complex IV), replaces NDUFA4 in Complex IV during inflammation to lower mitochondrial membrane potential and reduce ROS production, leading to cyto-protection and dampened immune response. The MOCCI transcript also generates miR-147b, which targets the NDUFA4 mRNA with similar immune dampening effects as MOCCI, but simultaneously enhances RIG-I/MDA-5-mediated viral immunity. Our work uncovers a dual-component pleiotropic regulation of host inflammation and immunity by MOCCI (C15ORF48) for safeguarding the host during infection and inflammation.
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Affiliation(s)
- Cheryl Q. E. Lee
- grid.414735.00000 0004 0367 4692Institute of Medical Biology, A*STAR, Singapore, Singapore
| | - Baptiste Kerouanton
- grid.428397.30000 0004 0385 0924Duke-NUS Medical School, Program in Cardiovascular and Metabolic Disorders, Singapore, Singapore
| | - Sonia Chothani
- grid.428397.30000 0004 0385 0924Duke-NUS Medical School, Program in Cardiovascular and Metabolic Disorders, Singapore, Singapore
| | - Shan Zhang
- grid.428397.30000 0004 0385 0924Duke-NUS Medical School, Program in Cardiovascular and Metabolic Disorders, Singapore, Singapore
| | - Ying Chen
- grid.418812.60000 0004 0620 9243Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore
| | - Chinmay Kumar Mantri
- grid.428397.30000 0004 0385 0924Duke-NUS Medical School, Program in Emerging Infectious Diseases, Singapore, Singapore
| | - Daniella Helena Hock
- grid.1008.90000 0001 2179 088XDepartment of Biochemistry and Molecular Biology, The Bio21 Molecular Science & Biotechnology Institute, University of Melbourne, Melbourne, VIC Australia
| | - Radiance Lim
- grid.428397.30000 0004 0385 0924Duke-NUS Medical School, Program in Cardiovascular and Metabolic Disorders, Singapore, Singapore
| | - Rhea Nadkarni
- grid.428397.30000 0004 0385 0924Duke-NUS Medical School, Program in Cardiovascular and Metabolic Disorders, Singapore, Singapore
| | - Vinh Thang Huynh
- grid.418812.60000 0004 0620 9243Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore ,grid.59025.3b0000 0001 2224 0361Lee Kong Chian School of Medicine, Nanyang Technological University Singapore, Singapore, Singapore
| | - Daryl Lim
- grid.418377.e0000 0004 0620 715XGenome Institute Singapore, A*STAR, Singapore, Singapore
| | - Wei Leong Chew
- grid.418377.e0000 0004 0620 715XGenome Institute Singapore, A*STAR, Singapore, Singapore
| | - Franklin L. Zhong
- grid.59025.3b0000 0001 2224 0361Nanyang Technological University, Skin Diseases and Wound Repair Program, Singapore, Singapore ,grid.185448.40000 0004 0637 0221Skin Research Institute of Singapore, A*STAR, Singapore, Singapore
| | - David Arthur Stroud
- grid.1008.90000 0001 2179 088XDepartment of Biochemistry and Molecular Biology, The Bio21 Molecular Science & Biotechnology Institute, University of Melbourne, Melbourne, VIC Australia
| | - Sebastian Schafer
- grid.428397.30000 0004 0385 0924Duke-NUS Medical School, Program in Cardiovascular and Metabolic Disorders, Singapore, Singapore ,grid.419385.20000 0004 0620 9905National Heart Research Institute Singapore, National Heart Centre Singapore, Singapore, Singapore
| | - Vinay Tergaonkar
- grid.418812.60000 0004 0620 9243Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore ,grid.4280.e0000 0001 2180 6431Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Ashley L. St John
- grid.428397.30000 0004 0385 0924Duke-NUS Medical School, Program in Emerging Infectious Diseases, Singapore, Singapore ,grid.4280.e0000 0001 2180 6431Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore ,grid.189509.c0000000100241216Department of Pathology, Duke University Medical Center, Durham, NC USA
| | - Owen J. L. Rackham
- grid.428397.30000 0004 0385 0924Duke-NUS Medical School, Program in Cardiovascular and Metabolic Disorders, Singapore, Singapore
| | - Lena Ho
- grid.414735.00000 0004 0367 4692Institute of Medical Biology, A*STAR, Singapore, Singapore ,grid.428397.30000 0004 0385 0924Duke-NUS Medical School, Program in Cardiovascular and Metabolic Disorders, Singapore, Singapore ,grid.418812.60000 0004 0620 9243Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore
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Syenina A, Saron WAA, Jagaraj CJ, Bibi S, Arock M, Gubler DJ, Rathore APS, Abraham SN, St. John AL. Th1-Polarized, Dengue Virus-Activated Human Mast Cells Induce Endothelial Transcriptional Activation and Permeability. Viruses 2020; 12:v12121379. [PMID: 33276578 PMCID: PMC7761533 DOI: 10.3390/v12121379] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 11/17/2020] [Accepted: 11/23/2020] [Indexed: 11/27/2022] Open
Abstract
Dengue virus (DENV), an arbovirus, strongly activates mast cells (MCs), which are key immune cells for pathogen immune surveillance. In animal models, MCs promote clearance of local peripheral DENV infections but, conversely, also promote pathological vascular leakage when widely activated during systemic DENV infection. Since DENV is a human pathogen, we sought to ascertain whether a similar phenomenon could occur in humans by characterizing the products released by human MCs (huMCs) upon direct (antibody-independent) DENV exposure, using the phenotypically mature huMC line, ROSA. DENV did not productively infect huMCs but prompted huMC release of proteases and eicosanoids and induced a Th1-polarized transcriptional profile. In co-culture and trans-well systems, huMC products activated human microvascular endothelial cells, involving transcription of vasoactive mediators and increased monolayer permeability. This permeability was blocked by MC-stabilizing drugs, or limited by drugs targeting certain MC products. Thus, MC stabilizers are a viable strategy to limit MC-promoted vascular leakage during DENV infection in humans.
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Affiliation(s)
- Ayesa Syenina
- Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore 169857, Singapore; (A.S.); (W.A.A.S.); (C.J.J.); (D.J.G.); (S.N.A.)
| | - Wilfried A. A. Saron
- Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore 169857, Singapore; (A.S.); (W.A.A.S.); (C.J.J.); (D.J.G.); (S.N.A.)
| | - Cyril J. Jagaraj
- Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore 169857, Singapore; (A.S.); (W.A.A.S.); (C.J.J.); (D.J.G.); (S.N.A.)
| | - Siham Bibi
- Laboratory of Molecular and Cellular Oncology, LBPA CNRS UMR8113, Ecole Normale Supérieure de Cachan, 94235 Cachan, France; (S.B.); (M.A.)
| | - Michel Arock
- Laboratory of Molecular and Cellular Oncology, LBPA CNRS UMR8113, Ecole Normale Supérieure de Cachan, 94235 Cachan, France; (S.B.); (M.A.)
- Laboratory of Hematology, Pitié-Salpêtrière Hospital, Pierre et Marie Curie University, 75005 Paris, France
| | - Duane J. Gubler
- Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore 169857, Singapore; (A.S.); (W.A.A.S.); (C.J.J.); (D.J.G.); (S.N.A.)
| | - Abhay P. S. Rathore
- Pathology Department, Duke University Medical Center, Durham, NC 27710, USA;
| | - Soman N. Abraham
- Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore 169857, Singapore; (A.S.); (W.A.A.S.); (C.J.J.); (D.J.G.); (S.N.A.)
- Pathology Department, Duke University Medical Center, Durham, NC 27710, USA;
- Immunology Department, Duke University Medical Center, Durham, NC 27710, USA
- Molecular Genetics and Microbiology Departments, Duke University Medical Center, Durham, NC 27710, USA
| | - Ashley L. St. John
- Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore 169857, Singapore; (A.S.); (W.A.A.S.); (C.J.J.); (D.J.G.); (S.N.A.)
- Pathology Department, Duke University Medical Center, Durham, NC 27710, USA;
- Department of Microbiology and Immunology, National University of Singapore, Singapore 117545, Singapore
- SingHealth Duke-NUS Global Health Institute, Singapore 169857, Singapore
- Correspondence:
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5
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Freije CA, Myhrvold C, Boehm CK, Lin AE, Welch NL, Carter A, Metsky HC, Luo CY, Abudayyeh OO, Gootenberg JS, Yozwiak NL, Zhang F, Sabeti PC. Programmable Inhibition and Detection of RNA Viruses Using Cas13. Mol Cell 2019; 76:826-837.e11. [PMID: 31607545 PMCID: PMC7422627 DOI: 10.1016/j.molcel.2019.09.013] [Citation(s) in RCA: 237] [Impact Index Per Article: 47.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/18/2019] [Accepted: 09/06/2019] [Indexed: 12/23/2022]
Abstract
The CRISPR effector Cas13 could be an effective antiviral for single-stranded RNA (ssRNA) viruses because it programmably cleaves RNAs complementary to its CRISPR RNA (crRNA). Here, we computationally identify thousands of potential Cas13 crRNA target sites in hundreds of ssRNA viral species that can potentially infect humans. We experimentally demonstrate Cas13's potent activity against three distinct ssRNA viruses: lymphocytic choriomeningitis virus (LCMV); influenza A virus (IAV); and vesicular stomatitis virus (VSV). Combining this antiviral activity with Cas13-based diagnostics, we develop Cas13-assisted restriction of viral expression and readout (CARVER), an end-to-end platform that uses Cas13 to detect and destroy viral RNA. We further screen hundreds of crRNAs along the LCMV genome to evaluate how conservation and target RNA nucleotide content influence Cas13's antiviral activity. Our results demonstrate that Cas13 can be harnessed to target a wide range of ssRNA viruses and CARVER's potential broad utility for rapid diagnostic and antiviral drug development.
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Affiliation(s)
- Catherine A Freije
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; PhD Program in Virology, Division of Medical Sciences, Harvard Medical School, Boston, MA 02115, USA.
| | - Cameron Myhrvold
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA.
| | - Chloe K Boehm
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA
| | - Aaron E Lin
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; PhD Program in Virology, Division of Medical Sciences, Harvard Medical School, Boston, MA 02115, USA
| | - Nicole L Welch
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; PhD Program in Virology, Division of Medical Sciences, Harvard Medical School, Boston, MA 02115, USA
| | - Amber Carter
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA
| | - Hayden C Metsky
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA 02142, USA
| | - Cynthia Y Luo
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Omar O Abudayyeh
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Department of Brain and Cognitive Science, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA; Department of Health Sciences and Technology, MIT, Cambridge, MA 02139, USA
| | - Jonathan S Gootenberg
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Department of Brain and Cognitive Science, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA; Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Nathan L Yozwiak
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
| | - Feng Zhang
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Department of Brain and Cognitive Science, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA; Howard Hughes Medical Institute (HHMI), Chevy Chase, MD 20815, USA
| | - Pardis C Sabeti
- Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA 02142, USA; PhD Program in Virology, Division of Medical Sciences, Harvard Medical School, Boston, MA 02115, USA; Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA; Howard Hughes Medical Institute (HHMI), Chevy Chase, MD 20815, USA; Department of Immunology and Infectious Disease, T.H. Chan Harvard School of Public Health, Boston, MA 02115, USA.
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6
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Japanese encephalitis virus neuropenetrance is driven by mast cell chymase. Nat Commun 2019; 10:706. [PMID: 30742008 PMCID: PMC6370868 DOI: 10.1038/s41467-019-08641-z] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 01/16/2019] [Accepted: 01/23/2019] [Indexed: 12/22/2022] Open
Abstract
Japanese encephalitis virus (JEV) is a leading cause of viral encephalitis. However, the mechanisms of JEV penetration of the blood-brain-barrier (BBB) remain poorly understood. Mast cells (MCs) are granulated innate immune sentinels located perivascularly, including at the BBB. Here we show that JEV activates MCs, leading to the release of granule-associated proteases in vivo. MC-deficient mice display reduced BBB permeability during JEV infection compared to congenic wild-type (WT) mice, indicating that enhanced vascular leakage in the brain during JEV infection is MC-dependent. Moreover, MCs promoted increased JEV infection in the central nervous system (CNS), enhanced neurological deficits, and reduced survival in vivo. Mechanistically, chymase, a MC-specific protease, enhances JEV-induced breakdown of the BBB and cleavage of tight-junction proteins. Chymase inhibition reversed BBB leakage, reduced brain infection and neurological deficits during JEV infection, and prolonged survival, suggesting chymase is a novel therapeutic target to prevent JEV encephalitis. How Japanese encephalitis virus (JEV) penetrates the blood-brain barrier (BBB) remains unclear. Here, using a genetic mouse model and a virulent JEV strain, the authors show that perivascular mast cells (MC) mediate JEV neuroinvasion and identify the MC-protease chymase as a potential therapeutic target.
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Mantri CK, St John AL. Immune synapses between mast cells and γδ T cells limit viral infection. J Clin Invest 2019; 129:1094-1108. [PMID: 30561384 DOI: 10.1172/jci122530] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 12/11/2018] [Indexed: 02/01/2023] Open
Abstract
Mast cells (MCs) are immune sentinels, but whether they also function as antigen-presenting cells (APCs) remains elusive. Using mouse models of MC deficiency, we report on MC-dependent recruitment and activation of multiple T cell subsets to the skin and draining lymph nodes (DLNs) during dengue virus (DENV) infection. Newly recruited and locally proliferating γδ T cells were the first T cell subset to respond to MC-driven inflammation, and their production of IFN-γ was MC dependent. MC-γδ T cell conjugates were observed consistently in infected peripheral tissues, suggesting a new role for MCs as nonconventional APCs for γδ T cells. MC-dependent γδ T cell activation and proliferation during DENV infection required T cell receptor (TCR) signaling and the nonconventional antigen presentation molecule endothelial cell protein C receptor (EPCR) on MCs. γδ T cells, not previously implicated in DENV host defense, killed infected targeted DCs and contributed to the clearance of DENV in vivo. We believe immune synapse formation between MCs and γδ T cells is a novel mechanism to induce specific and protective immunity at sites of viral infection.
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Affiliation(s)
- Chinmay Kumar Mantri
- Program in Emerging Infectious Diseases, Duke-National University of Singapore (Duke-NUS) Medical School, Singapore
| | - Ashley L St John
- Program in Emerging Infectious Diseases, Duke-National University of Singapore (Duke-NUS) Medical School, Singapore.,Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA.,Department of Microbiology and Immunology, Young Loo Lin School of Medicine, National University of Singapore, Singapore
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Syenina A, Jagaraj CJ, Aman SAB, Sridharan A, St John AL. Dengue vascular leakage is augmented by mast cell degranulation mediated by immunoglobulin Fcγ receptors. eLife 2015; 4. [PMID: 25783751 PMCID: PMC4362203 DOI: 10.7554/elife.05291] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 02/23/2015] [Indexed: 12/27/2022] Open
Abstract
Dengue virus (DENV) is the most significant human arboviral pathogen and causes ∼400 million infections in humans each year. In previous work, we observed that mast cells (MC) mediate vascular leakage during DENV infection in mice and that levels of MC activation are correlated with disease severity in human DENV patients (St John et al., 2013b). A major risk factor for developing severe dengue is secondary infection with a heterologous serotype. The dominant theory explaining increased severity during secondary DENV infection is that cross-reactive but non-neutralizing antibodies promote uptake of virus and allow enhanced replication. Here, we define another mechanism, dependent on FcγR-mediated enhanced degranulation responses by MCs. Antibody-dependent mast cell activation constitutes a novel mechanism to explain enhanced vascular leakage during secondary DENV infection.
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Affiliation(s)
- Ayesa Syenina
- Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore, Singapore
| | - Cyril J Jagaraj
- Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore, Singapore
| | - Siti A B Aman
- Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore, Singapore
| | - Aishwarya Sridharan
- Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore, Singapore
| | - Ashley L St John
- Program in Emerging Infectious Diseases, Duke-National University of Singapore, Singapore, Singapore
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9
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Juarez D, Long KC, Aguilar P, Kochel TJ, Halsey ES. Assessment of plaque assay methods for alphaviruses. J Virol Methods 2012; 187:185-9. [PMID: 23085307 DOI: 10.1016/j.jviromet.2012.09.026] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Revised: 09/19/2012] [Accepted: 09/28/2012] [Indexed: 12/28/2022]
Abstract
Viruses from the Alphavirus genus are responsible for numerous arboviral diseases impacting human health throughout the world. Confirmation of acute alphavirus infection is based on viral isolation, identification of viral RNA, or a fourfold or greater increase in antibody titers between acute and convalescent samples. In convalescence, the specificity of antibodies to an alphavirus may be confirmed by plaque reduction neutralization test. To identify the best method for alphavirus and neutralizing antibody recognition, the standard solid method using a cell monolayer overlay with 0.4% agarose and the semisolid method using a cell suspension overlay with 0.6% carboxymethyl cellulose (CMC) overlay were evaluated. Mayaro virus, Una virus, Venezuelan equine encephalitis virus (VEEV), and Western equine encephalitis virus (WEEV) were selected to be tested by both methods. The results indicate that the solid method showed consistently greater sensitivity than the semisolid method. Also, a "semisolid-variant method" using a 0.6% CMC overlay on a cell monolayer was assayed for virus titration. This method provided the same sensitivity as the solid method for VEEV and also had greater sensitivity for WEEV titration. Modifications in plaque assay conditions affect significantly results and therefore evaluation of the performance of each new assay is needed.
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Affiliation(s)
- Diana Juarez
- U.S. Naval Medical Research Unit No. 6, American Embassy, 3230 Lima, PI, Washington, DC 20521-3230, USA.
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RAPP F. VARIANTS OF HERPES SIMPLEX VIRUS: ISOLATION, CHARACTERIZATION, AND FACTORS INFLUENCING PLAQUE FORMATION. J Bacteriol 1996; 86:985-91. [PMID: 14080811 PMCID: PMC278556 DOI: 10.1128/jb.86.5.985-991.1963] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Rapp, Fred (Baylor University College of Medicine, Houston, Tex.). Variants of herpes simplex virus: isolation, characterization, and factors influencing plaque formation. J. Bacteriol. 86:985-991. 1963.-Variants of herpes simplex virus were isolated which differed in plaque size and in virulence for rabbits and mice. Keratitis on the rabbit cornea and generalized disease were associated with the large, but not the small, plaque variants. The large plaque variants were about as neurovirulent as was the parent strain for weanling mice, but the majority of the small plaque variants were only 1% as virulent for mice as was the parent virus. Agar inhibited the formation of plaques by the parent strain and all variants tested; development of plaques was retarded and the number of plaques was approximately 60% less than those developing under an overlay in which methyl cellulose had been substituted for the agar. Rabbit kidney cells and human embryonic lung fibroblasts were more sensitive than mouse embryo fibrolasts to infection with all variants tested.
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Abstract
Dengue, a major public health problem throughout subtropical and tropical regions, is an acute infectious disease characterized by biphasic fever, headache, pain in various parts of the body, prostration, rash, lymphadenopathy, and leukopenia. In more severe or complicated dengue, patients present with a severe febrile illness characterized by abnormalities of hemostasis and increased vascular permeability, which in some instances results in a hypovolemic shock. Four distinct serotypes of the dengue virus (dengue-1, dengue-2, dengue-3, and dengue-4) exist, with numerous virus strains found worldwide. Molecular cloning methods have led to a greater understanding of the structure of the RNA genome and definition of virus-specific structural and nonstructural proteins. Progress towards producing safe, effective dengue virus vaccines, a goal for over 45 years, has been made.
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Affiliation(s)
- E A Henchal
- Department of Virus Diseases, Walter Reed Army Institute of Research, Washington 20307-5100
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Yamamoto N, Kimura T, Ohyama A. Multiplication and distribution of type 2 dengue and Japanese encephalitis viruses in Toxorhynchites splendens after intrathoracic inoculation. Arch Virol 1987; 97:37-47. [PMID: 2891346 DOI: 10.1007/bf01310732] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The nonhematophagous mosquito Toxorhynchites (Tx.) splendens was found to be the most susceptible to type 2 dengue (D-2) and Japanese encephalitis (JEV) viruses among three hosts examined by virus titration and replication assays. After inoculation with D-2, the number of viral antigen positive cells in the head, thorax and abdomen increased up to day 15 and D-2 reached the maximum titer of 8.4 log10 PFU/g in the head on day 15. Hemocytes were the earliest cell type that could be detected as D-2 antigen positive on day 2. Multiplication of JEV was faster than that of D-2 in the mosquito. The number of JEV antigen positive cells in each part of the mosquito increased up to day 3, JEV reaching the maximum titer of 8.0 log10 PFU/g in the abdomen on day 3. Hemocytes and fat body cells (FBC) could be detected as JEV antigen positive cells on day 1. The time course of D-2 and JEV infection suggested that intrathoracically inoculated viruses were probably initially phagocytosed by hemocytes and/or FBC, and multiplied primarily in their cytoplasm. The infected hemocytes were then transported by the flow of body fluid and viruses were disseminated to other susceptible organs, such as ganglia, salivary glands, etc. The results obtained indicate that the course of infection of D-2 and JEV in Tx. splendens is similar to that in vector mosquitoes. Tx. splendens is therefore very useful for the study of these viruses.
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Affiliation(s)
- N Yamamoto
- Department of Microbiology, Kansai Medical University, Osaka, Japan
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14
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Wiharta AS, Hotta H, Hotta S, Matsumura T, Tsuji M. Increased multiplication of dengue virus in mouse peritoneal macrophage cultures by treatment with extracts of Ascaris-Parascaris parasites. Microbiol Immunol 1985; 29:337-48. [PMID: 3894890 DOI: 10.1111/j.1348-0421.1985.tb00832.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Methylcellulose-elicited peritoneal macrophages from BALB/c mice were cultivated in vitro and inoculated with dengue virus (DV). At intervals thereafter portions of the culture fluids were taken and titrated for viral infectivity. Extracts from Ascaris suum and Parascaris equorum, either crude or Sephadex G-100 fractionated, were examined for effects on the multiplication of DV. The macrophage cultures treated with the above substances produced larger amounts of DV compared with untreated control cultures. The enhancing effect of the substances depended on doses added and duration of treatment and was suppressed by co-treatment with carrageenan, a specific macrophage-inhibiting agent, but was not related to the viability of cultured cells. In fluorescent antibody (FA) as well as infectious center assay experiments, it was shown that the DV-infected cells were found more frequently in treated cultures than in untreated control cultures. In the treated cultures phagocytosis by cultured cells was also of a higher magnitude than that in untreated cultures. In cocultures of macrophages and splenocytes from the same line of mice, no additive effect of splenocytes was noted. The limulus amebocyte lysate clotting enzyme reaction (Limulus test) indicated that involvement of bacterial lipopolysaccharides in the enhancement phenomena was negligible. The data so far obtained suggest that the enhancing effect was due to direct action of the parasitic extracts on macrophages. Four Sephadex G-100 fractions from the crude extracts showed similar activities; however, the effects of fractions I and III appeared to be comparatively strong. Significance of the findings in relation to the pathogenesis of DV infection was discussed.
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15
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Hotta H, Hotta S, Takada H, Kotani S, Tanaka S, Ohki M. Enhancement of dengue virus type 2 replication in mouse macrophage cultures by bacterial cell walls, peptidoglycans, and a polymer of peptidoglycan subunits. Infect Immun 1983; 41:462-9. [PMID: 6874066 PMCID: PMC264663 DOI: 10.1128/iai.41.2.462-469.1983] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The effects of bacterial cell walls, peptidoglycans, and a water-soluble polymer of peptidoglycan subunits on dengue virus type 2 replication in cultured mouse peritoneal macrophages were studied. Pretreatment of macrophage cultures with all of test cell walls isolated from seven bacterial species for 3 days significantly enhanced the virus production in the cultures. Peptidoglycans prepared from four of the above cell walls also exerted the virus production-enhancing effects in a similar manner as the walls. A water-soluble polymer of peptidoglycan subunits which was prepared by treatment of Staphylococcus epidermidis wall peptidoglycan with an interpeptide bridge-splitting enzyme (endopeptidase) also definitely enhanced the virus production in macrophage cultures, although its activity was weaker than that of the original wall and peptidoglycan. Macrophage cultures from athymic nude mice, when treated with cell walls and peptidoglycans of S. epidermidis and Lactobacillus plantarum for 3 days, also showed an increased ability to support dengue virus type 2 replication. The infectious center assay demonstrated that the virus replication enhancement by S. epidermidis cell wall and peptidoglycan was primarily due to an increase in the number of virus-infected cells. This finding did not seem to be in conflict with the observation that macrophages treated with the above cell wall or peptidoglycan phagocytized more latex particles than did untreated macrophages. The conclusions based on the above experiments are that the treatment of mouse peritoneal macrophage cultures with bacterial cell walls and their components increases the take of dengue virus type 2 by macrophages and thus raises the virus production in the macrophage cultures.
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16
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Abstract
A simple and rapid microplaque assay for Sindbis virus was developed which uses microtiter plates and overlay medium consisting of methylcellulose and specific antibody to Sindbis virus. Discrete plaque formation was consistently observed on baby hamster kidney (BHK-15) cells within 24 h. The assay was reproducible, quantitative, and had about the same sensitivity as the agar overlay technique on chicken embryo cells in 35-mm petri dishes. The microplaque assay could be accurately applied to measuring interferon activity, particularly at low interferon levels. Overall, the microassay methods described here for assay of Sindbis virus yields and interferon activity retain the accuracy of chicken cell macroplaque assays while offering greater simplicity, rapidity, and economy of materials. This assay is also potentially applicable for use with other togaviruses.
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17
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Sanchez Legrand F, Hotta S. Susceptibility of cloned Toxorhynchites amboinensis cells to dengue and Chikungunya viruses. Microbiol Immunol 1983; 27:101-5. [PMID: 6135139 DOI: 10.1111/j.1348-0421.1983.tb03561.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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18
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Watanabe T, Horikawa Y, Sato K, Saito H. Methylcellulose media for plaque assay of murine leukemia virus. J Clin Microbiol 1982; 16:542-4. [PMID: 6290531 PMCID: PMC272405 DOI: 10.1128/jcm.16.3.542-544.1982] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
When ecotropic murine leukemia virus was assayed by a methylcellulose-XC cell procedure, plaque titers showed less test-to-test variation, more uniform dose-response curves, and larger plaque sizes, as compared with results of the conventional liquid overlay-XC cell test system. This assay therefore seems to be reliable and useful for the titration of ecotropic murine leukemia virus.
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19
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Hotta H, Hotta S. Dengue virus multiplication in cultures of mouse peritoneal macrophages: effects of macrophage activators. Microbiol Immunol 1982; 26:665-76. [PMID: 7176969 DOI: 10.1111/j.1348-0421.1982.tb00210.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Dengue-2 virus multiplied in cultures of methylcellulose-induced peritoneal macrophages of BALB/c mice. The in vitro-cultivated macrophages from dengue-1 virus-immune mice produced larger amounts of dengue-2 virus than did those from nonimmune controls. The effect of macrophage activators was examined by using nonimmune macrophages. Enhanced virus production was demonstrated in cultures of macrophagges pretreated with phytohemagglutinin (PHA) or bacterial lipopolysaccharide (LPS). The number of virus-infected cells in the pretreated cultures was estimated to be about 0.01% or less of the total macrophages. Continuous treatment of macrophages with PHA before and after virus inoculation brought about the most marked enhancement of dengue-2 virus multiplication. On the other hand, treatment with concanavalin A or pokeweed mitogen showed little effect on the multiplication of the same virus. Treatment with carrageenan, a specific macrophage blocking agent, markedly suppressed dengue-2 virus production in both dengue-1 virus-immune macrophages and LPS-treated macrophages. The indirect fluorescent-antibody (FA) technique revealed dengue-2 viral antigen in the cytoplasm of infected macrophages, and the FA-positive macrophages were more numerous in PHA-treated cultures than in untreated controls. The results obtained are discussed in relation to a possible role of activated monocytes/macrophages in the pathogenesis of dengue hemorrhagic fever.
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20
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Trépanier P, Payment P, Trudel M. A simple and rapid microassay for the titration of human respiratory syncytial virus. J Virol Methods 1980; 1:343-7. [PMID: 7014578 DOI: 10.1016/0166-0934(80)90051-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A microassay, using tissue culture microplates for the titration of human respiratory syncytial virus by syncytium formation, is described. Virus titers obtained agreed well with those obtained in a larger assay system; the microassay, however, is more rapid and economical. Large numbers of virus samples are easily and rapidly processed as the assay necessitates an incubation period of only three days.
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21
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Dubois DR, Berman S, Rourke SM, Timchak RL, Lowenthal JP. Cultivation of dengue virus type 2 in candidate substrates for vaccine production. JOURNAL OF BIOLOGICAL STANDARDIZATION 1978; 6:21-6. [PMID: 415061 DOI: 10.1016/s0092-1157(78)80029-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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22
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23
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Guskey LE, Jenkin HM. Adaptation of BHK-21 cells to growth in shaker culture and subsequent challenge by Japanese encephalitis virus. Appl Microbiol 1975; 30:433-8. [PMID: 1237269 PMCID: PMC187199 DOI: 10.1128/am.30.3.433-438.1975] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Baby hamster kidney (BHK-21) cells were adapted to grow in shaker culture using Waymouth medium 752/1 containing 20 mM N-2-hydroxyethyl-piperazine-N'-2'-ethanesulfonic acid buffer and supplemented with 2.5% (vol/vol) calf serum, 0.002% (wt/vol) sodium oleate, and 0.2% fatty acid-free bovine serum albumin (WO2.5). Infectivity of Japanese encephalitis virus grown in the cells adapted to WO2.5 approached 2 x 10(8) plaque-forming units per ml. The culture volume of infected cells was reduced fivefold 12 h after infection. This step resulted in a 10-fold increase in infectivity over that obtained from infected cultures not subjected to volume reduction.
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24
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Stollar V, Thomas VL. An agent in the Aedes aegypti cell line (Peleg) which causes fusion of Aedes albopictus cells. Virology 1975; 64:367-77. [PMID: 806166 DOI: 10.1016/0042-6822(75)90113-0] [Citation(s) in RCA: 177] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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25
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Makino S, Jenkin HM. Effect of fatty acids on growth of Japanese encephalitis virus cultivated in BHK-21 cells and phospholipid metabolism of the infected cells. J Virol 1975; 15:515-25. [PMID: 1167607 PMCID: PMC354488 DOI: 10.1128/jvi.15.3.515-525.1975] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Growth of Japanese encephalitis virus (JEV) in BHK-21 cells was stimulated in the presence of 20 to 40 mug of the sodium salt of oleic acid (cis-9-octadecenoic acid, 9-18:1) per ml supplemented in Waymouth medium. The stimulatory effect of the salt was highest when 9-18:1 was added after adsorption of the virus. Study of the effect of other fatty acids on growth of JEV showed the following results: the longer the chain length of the saturated fatty acid salt, the higher the stimulatory effect on viral growth. In contrast, polyunsaturated fatty acids had an inhibitory effect on viral growth. The effect of isomeric cis-octadecenoic acids on viral growth was variable, depending upon the position of the double bond. The cis-6-octadecenoic acid had the highest inhibitory effect on growth of JEV compared to other isomeric octadecenoic acids. The sodium salt of (1-14C) cis-9-octadecenoic acid (9-18:1, 20 mug/ml) was rapidly incorporated into control and JEV-infected cells. Specific radioactivity in phosphatidylcholine dropped 12 to 24 h after virus inoculation, whereas synthesis of phosphatidylethanolamine increased 12 to 24 h after virus inoculation in infected cells compared to uninfected cells. Results from these studies suggest that phospholipid metabolism of infected cells is markedly changed, which can be associated with altered fatty acid metabolism when using labeled 9-18:1 fatty acid as a marker.
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Stim TB. Dengue virus plaque development in simian cell systems. I. Factors influencing virus adsorption and variables in the agar overlay medium. Appl Microbiol 1970; 19:751-6. [PMID: 4987200 PMCID: PMC376782 DOI: 10.1128/am.19.5.751-756.1970] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Chemical and physical variables influencing the plaquing of all dengue serotypes in two simian cell systems were studied. Calf serum in the nutrient overlay may be replaced by mouse ascitic fluid or bovine plasma albumin when employing the rhesus monkey kidney LLC-MK(2) cell system for plaquing all dengue serotypes. Doubling the serum concentration in the overlay had little effect in modifying dengue types 1, 2, 3, and 4 plaque titers. Newborn agamma, 4-week-old and 8-week-old calf serum gave comparable titers with all dengue virus serotypes. Dengue virus titers, plaque size, and development time were unaffected by sodium bicarbonate concentrations ranging from 1.1 to 4.4 mg/ml of overlay. A twofold increase (0.00332 g%) in the amount of either autoclaved or filtered-sterilized neutral red reduced the dengue 2 virus titer as much as 2.2 logs. An increased Mg(++) and decreased Ca(++) concentration in the overlay medium increased the efficiency of the plaquing system.
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29
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Stim TB. Dengue virus plaque development in simian cell systems. II. Agar variables and effect of chemical additives. Appl Microbiol 1970; 19:757. [PMID: 4192886 PMCID: PMC376783 DOI: 10.1128/am.19.5.757-762.1970] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Dengue type 2 virus, strain New Guinea B, plaqued with equal facility and titer under overlays containing six different grades of commercial agar in the LLC-MK(2) cell system. Doubling the agar volume on LLC-MK(2) cell monolayers increased the plaque development time of dengue type 1, strain Hawaii. Storage of agar at 56 C reduced or totally abolished dengue type 4, strain H-241, plaque titer in LLC-MK(2) cells. The influence of six known virus plaque-enhancing compounds on plaque development of all dengue virus serotypes was studied in two continuous simian kidney cell lines, LLC-MK(2) and Vero. In the absence of any chemical additive, plaque development of all dengue serotypes was more rapid (4 to 10 days) in the LLC-MK(2) line than in the Vero line (6 to 13 days). Increased plaque development time of type 1, strain Hawaii, by pancreatin and plaque-size doubling of dengue types 1 and 4 was the only advantage conferred by the addition of six chemical additives in the LLC-MK(2) cell system. Dengue types 1 and 6 failed to plaque in the Vero cell system unless aided by a plaque-enhancing compound; plaques of dengue types 2, 3, 4, and 5 appeared sooner (2 days) and were increased in plaque diameter. The optimal DEAE concentration for plaquing dengue type 1, strain Hawaii, was 100 mug/ml; plaque development either failed at lower concentrations or was inhibited at higher (200 mug/ml) concentrations.
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30
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Spector S, Tauraso NM. Yellow fever virus. I. Development and evaluation of a plaque neutralization test. Appl Microbiol 1968; 16:1770-5. [PMID: 4973067 PMCID: PMC547757 DOI: 10.1128/am.16.11.1770-1775.1968] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Heretofore, the most reliable way of measuring yellow fever virus antibody was to use the mouse neutralization (MN) test employing either suckling or weanling mice. Certain disadvantages (e.g., expense both of animals and of maintaining a mouse colony, allergic reactions of many laboratory workers, and the relatively long time, 21 days, before end points are reached) are inherent in any program with mice or other laboratory animal species and have discouraged the use of the MN test by many laboratories. A previously reported plaque neutralization (PN) test with primary chick embryo cell cultures could not be consistently reproduced by later investigators. We have developed a convenient and reproducible PN test employing the MA-104 embryonic rhesus monkey kidney cell culture and a single agar-overlay procedure. When compared with MN tests with newborn (1 to 3 days old) and weanling (16 to 20 g, 24 to 28 days old) mice inoculated by the intracranial route, the PN test was the most sensitive for measuring neutralizing antibody; it was also less variable, less costly, and it achieved results in the shortest period of time. End points could be determined in 5 to 6 days for the PN test as compared to 21 days for the MN test.
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31
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Ueda Y, Tgaya I, Shiroki K. Immunological relationship between herpes simplex virus and B virus. ARCHIV FUR DIE GESAMTE VIRUSFORSCHUNG 1968; 24:231-44. [PMID: 4301658 DOI: 10.1007/bf01241295] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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32
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Dolan TM, Fenters JD, Fordyce PA, Holper JC. Rhinovirus plaque formation in WI-38 cells with methylcellulose overlay. Appl Microbiol 1968; 16:1331-6. [PMID: 4300170 PMCID: PMC547650 DOI: 10.1128/am.16.9.1331-1336.1968] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
A sensitive, reliable plaque assay system is described for five rhinoviruses using freshly prepared methylcellulose overlay and human embryonic diploid cells. Circular plaques with irregular edges, 2 mm in size, were formed by rhinoviruses 1A, 2, 6, and 13 after 6 or 7 days of incubation. A fifth rhinovirus, 17, formed a 1- to 2-mm feather plaque after 14 days of incubation. Plaque counts of rhinoviruses 1A and 13 were not affected by varying the pH of the overlay from 6.9 to 7.5. Plaque sizes and plaque-forming unit values of high passage rhinoviruses 1A and 13 were equivalent when tested at 26, 31, or 36 C. The rhinoviruses tested were sensitive to incubation at 40 C or heating at 50 C. Enhancement of plaques was observed when Mg(++) was incorporated into agar overlays, but enhancement did not occur when Mg(++) was added to methylcellulose overlays.
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Abstract
It has been assumed that plaque enhancement by cationic polymers is due to their binding of sulfated polysaccharides in agar. However, viruses that are enhanced by cationic polymers, diethylaminoethyl-dextran, and protamine were found not to be inhibited by polyanions in agar under the usual overlay conditions. In the case of adenovirus, enhancement by protamine seems to be due to the protamine serving as a source of arginine; enzymes released from the cultured cells digest the protamine and provide a reservoir of arginine for the cells. Other viruses (herpes and echovirus types 3, 4, 5, and 6) known to be susceptible to agar inhibitors were found to be enhanced by cationic polymers even under starch gel and methylcellulose overlays, which are free of polyanions. Since cationic polymers enhance the diffusion of virus through agar or starch gel, plaque enhancement seems to be the result of the gel becoming positively charged so that viruses can move effectively through them. The observation that starch gel and methylcellulose enhance plaque formation with viruses known to be inhibited under agar was also reinvestigated. When the consistency of the agar gel was reduced to the same viscosity of starch gel and methylcellulose overlays, the same plaque counts and sizes were observed under all three overlays.
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Abstract
Experiments with St. Louis encephalitis (SLE) virus have shown that neutral red enhances the plaque size in duck embryo cell cultures. This may represent a new method for genetic studies of SLE virus population. In a mosquito pool specimen NR(+) and NR(-) particles were demonstrated. By intracerebral passage in mice, there is a selection of NR(+) particles. Similar effects were not shown for eastern, western, and California encephalitis viruses. Plaques formed by the latter virus, however, were significantly reduced in number by neutral red.
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35
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36
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Gilbert VE, Kirkbride SC. Potassium-deficient medium as a reversible nontoxic inhibitor of ECHO 12 virus replication. Virology 1967; 32:539-41. [PMID: 6028946 DOI: 10.1016/0042-6822(67)90308-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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37
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Zee YC, Hackett AJ. Development of plaque assay for vesicular exanthema of swine virus (VESV) under methyl cellulose overlay. ARCHIV FUR DIE GESAMTE VIRUSFORSCHUNG 1967; 21:53-60. [PMID: 5628589 DOI: 10.1007/bf01258476] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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38
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Ichikawa Y, Pluznik DH, Sachs L. In vitro control of the development of macrophage and granulocyte colonies. Proc Natl Acad Sci U S A 1966; 56:488-95. [PMID: 5229970 PMCID: PMC224399 DOI: 10.1073/pnas.56.2.488] [Citation(s) in RCA: 284] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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39
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Stevens TM, Schlesinger RW. Studies on the nature of dengue viruses. I. Correlation of particle density, infectivity, and RNA content of type 2 virus. Virology 1965; 27:103-12. [PMID: 5828097 DOI: 10.1016/0042-6822(65)90147-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Abstract
Trent, Dennis
W. (University of Oklahoma School of Medicine, Oklahoma City)
and L. Vernon Scott
. Colorado tick fever virus in cell culture. I. Cell-type susceptibility and interaction with L cells. J. Bacteriol.
88:
702–708. 1964.—Colorado tick fever (CTF) virus was serially propagated in monolayer cultures of L and FL cells. Early passages of virus in FL cells yielded viral titers 10
4
-fold greater than did the corresponding L-cell passages. During L-cell passage number 4, there was a 10
3
-fold increase in the amount of infectious virus produced as compared with virus cultured earlier in this cell line. Viruses from L-cell passages 8 and 12 were identified with specific immune serum to be CTF viruses which were antigenically similar, if not identical, to the mouse-adapted virus. Parallel titrations of mouse-, L cell-, and FL cell-adapted viruses were performed in mice and replicate monolayers of L, FL, HeLa, KB, chick embryo, and cotton rat kidney cells. Cytopathic effects and viral replication were noted in all cultures except HeLa and cotton rat kidney. Cultures of L, FL, and chick embryo cells were as sensitive to infection as were suckling or weanling mice. KB cells were the least susceptible of those cell types examined. In L-cell cultures, 90% of the input virus was adsorbed to the cells during the first 30 min of incubation. The latent period lasted 10 to 12 hr, and was followed by rapid viral synthesis for the next 10 to 24 hr, depending upon the multiplicity of infection. Curves describing exponential increase in cell-associated and cell-released virus were separated by 4 hr. When the maximal total virus titers were reached, 80 to 90% of the virus was released from the cell.
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Dependence of adenovirus replication on arginine and inhibition of plaque formation by pleuropneumonia-like organisms. Virology 1963. [DOI: 10.1016/0042-6822(63)90125-9] [Citation(s) in RCA: 95] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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45
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SCHULZE IT, SCHLESINGER RW. Inhibition of infectious and hemagglutinating properties of type 2 dengue virus by aqueous agar extracts. Virology 1963; 19:49-57. [PMID: 13987274 DOI: 10.1016/0042-6822(63)90023-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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