Chemistry: molecular biology and microbiology – Virus or bacteriophage – except for viral vector or... – Recovery or purification
Patent
1998-05-22
1999-12-28
Wortman, Donna C.
Chemistry: molecular biology and microbiology
Virus or bacteriophage, except for viral vector or...
Recovery or purification
4352351, 4242041, 4242091, 4242241, C12N 702, A61K 3912
Patent
active
060080361
DESCRIPTION:
BRIEF SUMMARY
The invention relates to the field of purification of viruses, and more particularly to the purification of viruses obtained by culturing on cell lines.
Harvests of viruses obtained from culturing on cell lines such as Vero cells contain not only the desired viruses but also proteins and DNA originating from the culture cells. However, when the viruses are intended for certain uses, such as the manufacture of vaccines, it is essential for them to be as pure as possible. This is because standards exist which limit, to 100.multidot.10.sup.-12 g/vaccinal dose, the maximum authorized amount of cellular DNA in vaccines comprising products obtained from continuous and heteroploid cell lines.
Methods for purifying viruses are known in the prior art. Thus, U.S. Pat. No. 4,664,912 discloses in particular a method for purifying rabies virus by zone centrifugation in a sucrose gradient. However, such a method has the drawback of being difficult to automate; in addition, a prior inactivation step is necessary, which may lead to interactions between the virus and the cellular DNA which then make the step for removal of this DNA more difficult.
This reference also discloses a purification method combining a step of gel filtration and a step of ion-exchange chromatography. However, such a purification method does not allow maximum removal of the cellular DNA.
One aim of the invention is thus to propose a novel method for purifying viruses in very high yield which is easy to automate.
Another aim of the invention is to propose a purification method which allows whole, non-degraded viruses to be obtained.
To achieve these aims, the subject of the invention is a method for purifying viruses obtained from a cell line culture, this method consisting in separating by ion-exchange chromatography the viruses from the cell proteins and DNA originating from the culture, characterized in that it comprises at least one step of anion-exchange chromatography and one step of cation-exchange chromatography.
According to a particular characteristic of the method according to the invention, the step of cation-exchange chromatography is carried out after the step of anion-exchange chromatography. Optimized purification yields are thus obtained, compared with inversion of the order of the steps.
According to a particular embodiment, the method according to the invention also comprises a step of affinity chromatography by metal chelation. Thus, the amounts of residual DNA are truly reduced to a minimum.
According to another preferred embodiment, the method according to the invention also consists in carrying out all the chromatography steps at the same pH value. It is thus possible to automate the method easily and to reduce its costs appreciably, while at the same time maintaining its efficiency.
The invention will be better understood on reading the detailed description which follows.
The viruses to be purified according to the method of the invention are viruses obtained by means of cell lines, in particular continuous and heteroploid cell lines, which are thus liable to be combined with cellular DNA. These may be, in particular, rabies virus, Japanese encephalitis virus or influenza virus. These viruses to be purified may have been obtained by culturing on Vero cells on microsupports. This concerns, for example, rabies virus obtained by culturing, as is described in U.S. Pat. No. 4,664,912.
The viral harvest is filtered and then processed, according to the invention, by anion-exchange chromatography and by cation-exchange chromatography.
The anion-exchange chromatography can be an exchange chromatography of weak anions carried out, for example, using gel containing the diethylaminoethyl radical: DEAE Spherodex gel sold by Sepracor, DEAE Sepharose gel sold by Pharmacia, EMD DEAE gel sold by E. Merck. Although this is not common for the removal of nucleic acids, it is preferred to use a strong anion exchanger such as one of the following gels: High Q gel sold by Bio-Rad, Q Sepharose gel sold by Pharmacia, EMD TMAE gel sold by E. Merck.
All
REFERENCES:
patent: 4162192 (1979-07-01), Mizuno et al.
patent: 4525349 (1985-06-01), Montagnon et al.
patent: 4664912 (1987-05-01), Wiktor et al.
patent: 5837520 (1998-11-01), Shabram et al.
Chemical Abstracts, vol. 51, No. 1, Jan. 10, 1957, Columbus, Ohio, Abstract No. 530f, H.D. Matheka et al, "Ion Exchange For Virus Preparations. I. Influence Of The Ion-Exchange Properties On The Adsorption Of Influenza Virus", XP002000499 & Z. Naturforsch, vol. 11b, 1956, pp. 187-193.
Chemical Abstracts, vol. 51, No. 1, Jan. 10, 1957, Columbus, Ohio, Abstract No. 530g, H.D. Matheka et al, "Ion Exchange For Virus Preparations, II. Fractionation Of Influenza Virus" XP002000500 & Z. Naturforsch., vol. 11b, 1956, pp. 193-199.
Fanget Bernard
Francon Alain
Pasteur Merieux Serums et Vaccins
Wortman Donna C.
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