[go: up one dir, main page]

EP0748375A1 - Culture selective de virus - Google Patents

Culture selective de virus

Info

Publication number
EP0748375A1
EP0748375A1 EP95909066A EP95909066A EP0748375A1 EP 0748375 A1 EP0748375 A1 EP 0748375A1 EP 95909066 A EP95909066 A EP 95909066A EP 95909066 A EP95909066 A EP 95909066A EP 0748375 A1 EP0748375 A1 EP 0748375A1
Authority
EP
European Patent Office
Prior art keywords
virus
test
progeny
phage
target cell
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP95909066A
Other languages
German (de)
English (en)
Inventor
Gordon Sydney Anderson Birnie Stewart
Stephen Paul Denyer
Sabah Abdel Amir University of Guelph JASSIM
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
FOUNDATION FOR INNOVATIVE NEW DIAGNOSTICS
Original Assignee
Merck Patent GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Merck Patent GmbH filed Critical Merck Patent GmbH
Priority to EP95909066A priority Critical patent/EP0748375A1/fr
Publication of EP0748375A1 publication Critical patent/EP0748375A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N7/00—Viruses; Bacteriophages; Compositions thereof; Preparation or purification thereof
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K35/00—Medicinal preparations containing materials or reaction products thereof with undetermined constitution
    • A61K35/66—Microorganisms or materials therefrom
    • A61K35/76—Viruses; Subviral particles; Bacteriophages
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P31/00—Antiinfectives, i.e. antibiotics, antiseptics, chemotherapeutics
    • A61P31/04—Antibacterial agents
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N2795/00—Bacteriophages
    • C12N2795/00011—Details
    • C12N2795/10011—Details dsDNA Bacteriophages
    • C12N2795/10111—Myoviridae
    • C12N2795/10132—Use of virus as therapeutic agent, other than vaccine, e.g. as cytolytic agent
    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N2795/00—Bacteriophages
    • C12N2795/00011—Details
    • C12N2795/10011—Details dsDNA Bacteriophages
    • C12N2795/10111—Myoviridae
    • C12N2795/10151—Methods of production or purification of viral material

Definitions

  • This invention relates to infection of host cells by virus particles and selection of virus progeny which have an improved ability to infect host cells compared to the natural virus population.
  • Bacteriophage host interactions are dependent on the binding of tail proteins to specific bacterial surface receptors (Pelczar et al 1993) . The absence of such receptors or the infrequent expression of such receptors would render a bacterium resistant (or partially resistant) to bacteriophage infection. Similarly, failure to correctly assemble tail fibres would prevent efficient infection and it may be expected that there would be a Poisson type distribution of tail assembly efficiency giving, in any population of phage, some that attach rapidly and some weakly, if at all.
  • the bacteriophage protection technique allows for the complete destruction of bacteriophage that fail to enter the protective environment of a host bacterial cell within a specified time interval. It is now possible, therefore, to develop bacteriophage replication plaques from only those phage that rapidly attach to and replicate in a host bacterium. The progeny of such phage do not show a distribution of attachment equivalent to the original population but instead the entire population has a greatly enhanced efficiency of host attachment. A repetitive cycle of this technique can lead to a phage population with an entirely altered host affinity.
  • a phage population that might have previously provided only very weak infection of a host can be developed to a population giving a plaque forming unit (pfu) efficiency of 1 and a rapid replication rate.
  • pfu plaque forming unit
  • new viral agents different from those that could be obtained directly from nature, can be constructed.
  • the invention therefore provides a method of obtaining from a virus population comprising a test virus improved virus progeny of the test virus, which method comprises the steps of: (i) providing a target cell sample which comprises target cells of the test virus;
  • the virus progeny are improved eg. by having increased efficiency of infection of the target cell compared with the test virus, which may be due to improved attachment to the target cell, or to any other alteration that results in the virus being better able to attach to and/or infect the cell.
  • the improvement may thus be in the virulence of the virus.
  • the test virus is preferably a phage and may be a bacteriophage, in which case the target cell is a bacterium.
  • the "target cell” is not necessarily the usual wild type target for the phage; the target cell may be a cell type which is only very rarely infected by the phage in question.
  • the method according to the invention may be performed using phage Felix 01 as the test phage and Salmonella agona, infantis, kubacha, tocrba and Stanley as the target cell. Wild type Felix 01 does not normally efficiently infect these Salmonella species, although it infects other Salmonella species, such as S. tvphimurium, but by using the phage breeding method according to the invention, improved Felix 01 can be produced which has the ability to efficiently infect Salmonella agona, infantis, kubacha, to ⁇ ba and Stanley producing visible plaques.
  • an additional step performed between steps ii) and iii) comprises neutralising the extracellular virus with an antiviral agent.
  • Neutralisation of the virus means destroying or killing or any method of inactivating the virus.
  • WO92/02633 describes ways in which this can be achieved, without harming the target cell, for a method involving bacteria/bact.eriophage.
  • Neutralisation of extracellular virus may be carried out in other ways known in the art; some methods of neutralisation are demonstrated herein. The particular method used is not material to the invention.
  • the invention is discussed here primarily in relation to phage and bacterial host cells, the invention also covers breeding of viruses which infect eukaryotic cells, and the resulting progeny virus.
  • extracellular phage need not be neutralised chemically.
  • the extracellular phage may simply be separated from the target cells after the desired initial attachment/infection has taken place.
  • the incubation time in step (ii) above may be controlled to ensure partial but incomplete infection of the population.
  • the proportion of test phage present in the mixture which attaches to and infects the target cells is thereby controlled.
  • Physical or chemical conditions may also be altered for this purpose. The conditions and timing required for a particular combination of phage and target cell in the method according to the invention will be readily determined by a person skilled in the art.
  • the phage breeding method described herein can be performed more than once to produce highly infectious phage.
  • Phage progeny obtained from the first round of breeding are used as test phage in a repeat of the method according to the invention.
  • the second phage progeny will be better able to infect the target cell than the previous phage progeny. Any number of rounds of breeding may be performed.
  • Phage progeny may also be subsequently bred on a different target cell, so as to broaden the range of host affinity.
  • the invention provides virus progeny of a test virus, wherein the virus progeny have improved properties compared to the test virus, following one or more rounds of selective breeding.
  • the virus progeny may be obtained by the method described therein.
  • Such virus progeny are not found in nature because in nature there is no separation or neutralisation of extracellular virus once the more efficient virus particles have attached to and/or infected the target cell.
  • Yet another aspect of the invention is a new method of detecting virus infected cells.
  • the target cells which have been infected can be detected by the appearance in the culture of host cell nucleic acid or other intracellular markers.
  • This detection method may be used, for instance, in place of reporter ' " bacteria in the bacterial detection assay described in WO92/02633. It can also be used in conjunction with the virus breeding method described herein, to allow early detection of infected target cells and thereby further discrimination between efficient and inefficient virus.
  • the target cells containing the most rapidly multiplying virus will be detectable first.
  • the detection method employs ethidiu bromide (EtBr) or analogues eg. fluorochrome in the culture medium.
  • EtBr binds to nucleic acid and when bound, its fluorescence in ultra violet light increases (Kosarev and Puchkov, 1989) .
  • Plaques of virally infected cells in a culture plate are easily visible in the presence of EtBr; an automated system is also envisaged.
  • extracellular viral particles which have been neutralised do not obscure results; it is thought that Composition A, an anti-viral composition described herein in Example 1, destroys viral nucleic acid so that none binds the EtBr.
  • Phage with improved attachment and infectious properties, and increased specificity towards a specific host cell can be employed in the bacterial detection method described in WO92/02633. In that method, a chosen phage will infect and multiply only when brought into contact with its specific host cell. The amplified phage are then allowed to infect reporter bacteria and thereby produce an observable signal . Phage produced by the method according to the present invention, having a broader range of host affinity than wild type phage, may also be useful in bacterial detection assays.
  • phage for use in bio-therapy for bacterial infection in humans or animals Phage progeny can be selected for high killing levels.
  • Advantages of using phage for destroying bacterial pathogens include continued destruction of the bacteria once excreted, such as Salmonella in poultry, and prevention or reduction of the spread of antibiotic resistance.
  • the invention also opens up new possibilities for vaccine development. There are additional opportunities in the use of improved bacteriophage to control bacterial and other contamination by bioremediation eg. bacterial slime in paper production.
  • Composition A a. Preparation of Composition A a. Preparation of 4.3 mM FeSO .7H 0 in Lambda-buffer (6mM Tris-HCl pH7.2, lOmM MgS0 4 .7H 2 0, 50 ⁇ g/ml gelatin) .
  • Composition A was prepared 1-2 min prior to use by mixing 16.74 ml of 4.3 mM FeSO .7H Region0 (a; yellow) with 8.3 ml of 13% PRE (b; yellow) . After about 30 sec the colour of the mixture (a and b) changed greenish then to black. These mixtures of ferrous sulphate and PRE (a and b) should be protected from light.
  • Stage one was based on the bacteriophage protection technique, as published in WO92/02633; in brief: mix 10 ⁇ l of phage suspension (approximately 1 x 10 12 pfu/ml) with lO ⁇ l of bacterial cells suspension g (10 cfu/ml) and incubate at 37°C for 15 min.
  • Composition A prepared as described above
  • the neutraliser 166 ⁇ l of 2% (v/v) Tween 80 in Lambda-buffer
  • lOO ⁇ l of the same target bacteria 2.3 ml of Tryptose Phosphate Broth (TPB; Oxoid) supplemented with 0.4% (w/v) agar and 0.0001% (w/v) ethidium bromide (EtBr) .
  • TPB Tryptose Phosphate Broth
  • EtBr ethidium bromide
  • phage which are capable of infecting their target bacterial cell within 15 min have escaped the kinetic-killing process of Composition A and create a visible "fluorescent" plaque in the top layer agar. Extracellular phage which have failed to infect the target bacteria are killed.
  • the number of plaques obtained from the first round of this protocol are between 5 to 20 pfu of phage from an initial phage titre of 10 12pfu/ml.
  • the phage plaques were collected as one plaque per 100 ⁇ l of Lambda-buffer (6mM Tris, lOmM
  • the second stage involves preparing a large volume of the corresponding phage by the sloppy layer plaque technique as follows: A lOO ⁇ l sample of the stage 1 phage (10-fold serially diluted with Lambda- buffer) is mixed with 100 ⁇ l of an overnight TPB culture of the appropriate target bacteria in a sterile Eppendorf micro-centrifuge tube and incubated for 15 min at 37°C. To each Eppendorf tube is then added 2.3 ml of 'sloppy agar' (TPB supplemented with 0.4% (w/v) agar) , which has been melted and cooled to 40°C in a water bath.
  • TPB sterile Eppendorf micro-centrifuge tube
  • each tube is then well mixed by swirling, poured over the surface of a plate of tryptone phosphate agar (TPA) and allowed to set for 15 min at room temperature.
  • TPA tryptone phosphate agar
  • the plates are incubated for 18 h at 37°C, and a plate showing almost confluent plagues used to prepare a concentrated phage suspension by overlaying with 5ml of Lambda-buffer (titre 10 12 pfu/ml) .
  • phage Felix 01 gives a close parity between pfu and cfu when the bacterial cells are grown at 30-37°C for 18 h (Table 2) . Plaque formation for Felix 01 is clearly dependent on the culture incubation temperature.

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Organic Chemistry (AREA)
  • Animal Behavior & Ethology (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Genetics & Genomics (AREA)
  • Microbiology (AREA)
  • Wood Science & Technology (AREA)
  • Zoology (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Virology (AREA)
  • Engineering & Computer Science (AREA)
  • Biotechnology (AREA)
  • Biomedical Technology (AREA)
  • Oncology (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Communicable Diseases (AREA)
  • Biochemistry (AREA)
  • General Engineering & Computer Science (AREA)
  • Immunology (AREA)
  • Mycology (AREA)
  • Epidemiology (AREA)
  • Measuring Or Testing Involving Enzymes Or Micro-Organisms (AREA)
  • Micro-Organisms Or Cultivation Processes Thereof (AREA)
  • Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)
  • Medicines Containing Material From Animals Or Micro-Organisms (AREA)

Abstract

Procédé d'obtention, à partir d'une population de virus comprenant un virus d'essai, d'une descendance améliorée de ce virus d'essai, ce procédé comportant les étapes consistant: (i) à fournir un échantillon de cellules cibles comprenant des cellules cibles du virus d'essai; (ii) à faire incuber un mélange d'un échantillon de la population de ce virus avec l'échantillon de cellules cibles de manière à provoquer la fixation sur au moins une cellule cible d'au moins une particule virale d'essai, ou l'infection de cette cellule par cette particule, les conditions de l'incubation étant maîtrisées afin qu'une proportion souhaitée du virus d'essai n'infecte pas les bactéries cibles; (iii) à faire incuber les cellules cibles afin d'achever l'infection par le virus d'essai et provoquer la libération de la descendance du virus, et enfin à récupérer cette descendance. Dans un mode de réalisation préféré, une étape supplémentaire effectuée entre les étapes ii) et iii) consiste à neutraliser le virus extracellulaire à l'aide d'un agent antiviral.
EP95909066A 1994-03-01 1995-02-28 Culture selective de virus Withdrawn EP0748375A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP95909066A EP0748375A1 (fr) 1994-03-01 1995-02-28 Culture selective de virus

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
EP94301524 1994-03-01
EP94301524 1994-03-01
EP95909066A EP0748375A1 (fr) 1994-03-01 1995-02-28 Culture selective de virus
PCT/GB1995/000409 WO1995023848A1 (fr) 1994-03-01 1995-02-28 Culture selective de virus

Publications (1)

Publication Number Publication Date
EP0748375A1 true EP0748375A1 (fr) 1996-12-18

Family

ID=8217593

Family Applications (1)

Application Number Title Priority Date Filing Date
EP95909066A Withdrawn EP0748375A1 (fr) 1994-03-01 1995-02-28 Culture selective de virus

Country Status (6)

Country Link
EP (1) EP0748375A1 (fr)
JP (1) JPH09509831A (fr)
KR (1) KR100373798B1 (fr)
AU (1) AU1716295A (fr)
BR (1) BR9506962A (fr)
WO (1) WO1995023848A1 (fr)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB0511204D0 (en) * 2005-06-02 2005-07-06 Univ Birmingham Medicaments
GB2466177A (en) * 2008-12-03 2010-06-16 Arab Science & Technology Found Bacteriophage selection and breeding
AU2016353541A1 (en) * 2015-11-11 2018-06-21 Elizabeth Jayne ELLIOTT Method and apparatus of improved bacteriophage yield

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB771653A (en) * 1955-08-31 1957-04-03 Medico Biolog Lab Ltd Stabilized bacteriophages
US2851006A (en) * 1955-11-03 1958-09-09 Swift & Co Hatching of eggs
US4282315A (en) * 1979-09-13 1981-08-04 Corning Glass Works Preparation of enriched whole virus radioligand
GB9017443D0 (en) * 1990-08-09 1990-09-26 Amersham Int Plc Reporter bacteria for rapid microbial detection

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9523848A1 *

Also Published As

Publication number Publication date
KR100373798B1 (ko) 2003-12-31
AU1716295A (en) 1995-09-18
WO1995023848A1 (fr) 1995-09-08
BR9506962A (pt) 1997-09-16
JPH09509831A (ja) 1997-10-07

Similar Documents

Publication Publication Date Title
Gaudin et al. Extracellular membrane vesicles harbouring viral genomes
Brooks et al. Behavior of λ bacteriophage in a recombination deficient strain of Escherichia coli
Kaiser et al. Recombination between related temperate bacteriophages and the genetic control of immunity and prophage localization
Mindich et al. Isolation of nonsense mutants of lipid-containing bacteriophage PRD1
Luria et al. Transduction of lactose-utilizing ability among strains of E. coli and S. dysenteriae and the properties of the transducing phage particles
Jacquemot et al. Therapeutic potential of a new jumbo phage that infects Vibrio coralliilyticus, a widespread coral pathogen
Faruque et al. RS1 element of Vibrio cholerae can propagate horizontally as a filamentous phage exploiting the morphogenesis genes of CTXΦ
Rudd et al. Development and evaluation of an in vitro virus isolation procedure as a replacement for the mouse inoculation test in rabies diagnosis
Liu et al. Legionella pneumophila EnhC is required for efficient replication in tumour necrosis factor α‐stimulated macrophages
Gibbs et al. Satellite bacteriophage P4: characterization of mutants in two essential genes
Kuo et al. ES18, a general transducing phage for smooth and nonsmooth Salmonela typhimurium
Mandel Infectivity of phage P2 DNA in presence of helper phage
Tessman et al. Bacterial rep-mutations that block development of small DNA bacteriophages late in infection
Jamalludeen et al. Isolation and characterization of virulent bacteriophages against Escherichia coli serogroups O1, O2, and O78
Choi et al. Improved bactericidal efficacy and thermostability of Staphylococcus aureus-specific bacteriophage SA3821 by repeated sodium pyrophosphate challenges
EP0748375A1 (fr) Culture selective de virus
Donch et al. Loci of radiation sensitivity in Bs strains of Escherichia coli
Guo et al. Prophage LambdaSo uses replication interference to suppress reproduction of coexisting temperate phage MuSo2 in Shewanella oneidensis MR‐1
US8114622B2 (en) Methods for generation of reporter phages and immobilization of active bacteriophages on a polymer surface
Pfeifer et al. Mapping of gal--mutants by transducing λdg carrying deletions of the gal-region
Rigby et al. Properties and partial genetic characterization of Nepean phage and other lytic phages of Brucella species
Megha et al. Isolation and characterization of lytic coliphages from sewage water.
Campbell Prophages and cryptic prophages
Le Bacteriophage: A potential treatment for Citrus canker
Rohrmann et al. Characterization of DNA from three nuclear polyhedrosis viruses pathogenic for Choristoneura sp

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19960819

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE ES FR GB IT NL

17Q First examination report despatched

Effective date: 20000707

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: FOUNDATION FOR INNOVATIVE NEW DIAGNOSTICS

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20061031