DE3518595A1 - METHOD FOR CONCENTRATING VIRUSES - Google Patents

Description

GEYER, HAGEMANN & KEHL

PATENT LAWYERS EUROPEAN PATENTATTORNErS -

Ismaninger Straße 108 · 8000 Munich 80 · Telephone O089 / 980731-34 ■ Telex 5216136 hage d · Telegram: hageypatent · Fax 089/982421 Automat (CCITT Cr.2)

Postal address: P.O. Box 860329 8000 Munich 86

Technion Research & Munich, den

Development Foundation Ltd., May 23, 1985

Haifa, Israel Dr. H / 3 / cw

u.z .: Pat 77 / 3-85Ch

Method for concentrating viruses

The invention relates to a method for concentrating viruses from liquid waste and biological fluids.

Concentration of viruses from liquids is generally carried out with large volumes of liquid, The aim here is to maintain a small volume of liquid which enables the virus to be easily counted by routine measures using as many tissue culture dishes as possible. There are different procedures for concentrating various viruses from water. To these known methods include, for example, alginate membrane filtration, protamine precipitation, hydroextraction, two-phase separation, Ultrafiltration, aluminum hydroxide adsorption, polyelectrolyte adsorption and filtration through the Adsorption / elution method followed by flocculation of organic materials. The latter procedure is used most often. The measure of eluting includes the use of basic protein

containing solutions. As examples, a glycine buffer, a tryptose phosphate solution or broth, a trypticase soy broth, fetal bovine serum and (beef) meat extracts to be named. The last-mentioned eluent is most often used in laboratory technology, which is based on the Handbook of Virology (USEPA / Berg and Safferman, 1983).

The method based on meat extract involves the use of a 3% meat extract where the flocculation (organic materials) is based on the adsorption / elution process. Ss is here however, it has been recognized that different commercially available meat extract products result in different Virus re-enrichment results due to their nature lead to to form organic flocculants at a pH of 3.5. Commercially available products of this type are therefore one subject to special treatment that occurs in the manufacturing process is obviously required and which makes it unsuitable for (organic) flocculation.

It has been reported that the concentration of viruses on a smaller scale using erythrocyte cells is based either on a hemagglutination interaction or on passive hemagglutination. Hemagglutination has been used extensively for the detection of myxoviruses, around fluids of inoculated egg embryos. The hemagglutination properties of the viruses have also increased demarcating virus groups and subgroups have been found useful. Since some hemagglutination viruses under conditions which are not optimal for adsorption elute from the erythrocytes has been suggested Purify and concentrate the virus suspensions using relatively simple techniques. A number of

Virus is adsorbed by total erythrocytes at 4 ° C and eluted at 37 ° C and vice versa. However, this method can only be used when very small amounts of liquid are too high are treat. In addition, there are differences in the water quality with regard to the osmotic Pressure opposes the use of whole erythrocyte cells, which leads to hemolysis and the loss of hemagglutination properties going back.

A passive hemagglutination based assay was first used to detect viral antibodies. later there has been an expansion to a variety of viral antigens and antibodies thereof. With the test antigens was it generally a raw virus preparation such as tissue culture homogenates and infectious Alantoic fluids. Try to establish the quantitative relationship between the hemagglutination endpoint and to measure the absolute number of virus particles have remained inconclusive. Also in view In general, this method cannot concentrate on hemolysis of the entire erythrocyte be used on a large scale by viruses. In addition to the various disadvantages of the above Processes discussed were new adsorbent materials with a higher affinity for those to be concentrated various viruses found from time to time and suggested for particular viruses. One of the main disadvantages of all known methods is the variable effectiveness of the concentration of the Viruses.

The invention was therefore based on the object of a simple and highly effective method for concentration of viruses, which also allows the concentration of a wide range of viruses.

According to the invention this object is achieved in that

0RK3INAL INSPECTED

1 a) the fluids containing viruses with a

adsorbent matrix containing the shells of animal erythrocyte cells is brought into contact,

b) the mixture obtained according to measure (a)

is acidified, whereby the precipitation of viruses adsorbed on the shells of the animal erythrocyte cells is separated,

c) the precipitate obtained according to measure (b) is eluted into a solution which has a pH value above that prevails in measure (b), and

d) a concentrate of viruses is obtained.

These measures can be used with exceptional success for concentrating viruses from liquid waste, in particular from sewage or waste water, and biological fluids. The adsorbent matrix is preferably either in the form of a particulate solid material or a continuous film. The particulate solid materials of the adsorbent matrix can be either a bed in a column or in a cartridge. In addition, the adsorbent can be used in the form of a coating on a suitable carrier, such as glass or plastic beads. The particle size of the adsorbent can be in a wide range. A range from 1 to 20 μm is generally preferred. The use of the shells of animal erythrocyte ^{cells (erythrocyte 11} ghost cells) in the form of a continuous film is particularly preferred. This continuous film is preferably a membrane.

According to a preferred embodiment of the invention The method involves eluting the precipitates adsorbed on the shells of the animal erythrocyte cells Viruses carried out using a buffer solution with a pH above 6.5. That way will the extent to which the viruses are concentrated to a maximum

—Δ-mum raised. The most preferred buffer is a saline phosphate buffer with a pH of about 7.5.

The new adsorbing matrix has the following advantages, among others! There are high yields of virus concentrates achieved. The envelopes of the erythrocyte cells are very stable and therefore withstand many cycles adsorption / elution without deteriorating their properties. The adsorbent Matrix can be used to concentrate a wide range of viruses.

In contrast to the known proposals, the method according to the invention involves the coating of erythrocyte cells used, no risk of hemolysis associated. These erythrocyte cells can easy to manufacture. A simple method of making them is described in Kabat, Experimental

20 Immunochemistry, Thomas Pub. Second Edition, 1961,

P. 110. This procedure consists in collecting the casings of the erythrocyte cells from a large volume of distilled water saturated with carbon dioxide 4 ° C, after hemolysis. This mass is then centrifuged (preferably by means of a continuous working centrifuge of the flow system from Sorvall KSB-R), with cold solutions of sodium chloride (2 wt .-%) washed in a sodium ethyl mercury (II) thiosalicylate (1: 1 0. 000) containing saline solution sus--

30 pendants and stored in a refrigerator. the

Fixation of the cell envelope is carried out with 3% formaldehyde and the saline phosphate buffer (KPP) (0.01 M), where the ratios 1: 5: 5 (1 liter of erythrocyte cell envelopes + 5 liters of formaldehyde + 5 liters KPP). The mixture is left to stand at 37 ° C overnight while continuing Shaking is subjected. After fixation

the cell envelopes are centrifuged again and washed with a saline solution (0.8% by weight) to remove a Remove excess formaldehyde. To avoid microbial spoilage, becomes the cell shell material a preservative such as sodium azide is given. Immediately prior to using the red cell envelope these are washed again with a saline solution.

The inventive method can be carried out in a wide temperature range, the range from 4 to 37 ° C is preferred. This knowledge contradicts the statements of the state of the art, after which an increase in temperature

15 highlights (Zittle CA. 1953, Advances in Enzymology,

44: 319), since the development of proteins on the adsorbent surface is endothermic Represents reaction.

The concentration of the shells of the animal erythrocyte cells can be selected within a wide range of concentrations are, preferably in a range between 4 and 30 vol .-%. Below 4% seems a minor one Decrease in concentration efficiency to occur, while at a concentration above 30% no improvement in concentration efficiency is obtained.

The method of the invention becomes very easy and without the need for any use special equipment carried out. The adsorption / elution cycle of the method according to the invention to which the shells of animal erythrocyte cells are used, includes the following measures:

Measure 1 :

Containing the shells of animal erythrocyte follicles! Test-

-ΙΟΙ tubes are used at a given concentration vaccinated with a known amount of virus / bacteriophage. The pH of the solution is between 6.0 and 7.5.

5 measure 2 ;

The pH of the test specimen is lowered to 3.5 using a 0.1 N KCl solution. The mixture is on top Shaken for about 10 minutes. A complex of viruses attached to the shells of animal erythrocyte cells adsorbed becomes in the form of a precipitate after centrifuging the mixture for about 10 minutes obtain. The supernatant phase is used as a sample, while the rest is discarded.

15 measure 3 ;

The precipitation obtained according to measure 2, which the shells of the animal erythrocyte cells together with the contains viruses adsorbed thereon, becomes homogeneous again with KPP at a pH of about 7.5 with stirring

20 suspended.

The invention is illustrated below by means of examples in which the bacteriophages $ z5x-174, MS-2 and f2 are used as Models used are explained. However, the specification of these phages is not intended to limit the invention be seen. It is known that these phages are often used as models for studying enteroviruses in water be used because they are cheap and resistant to adverse environmental influences. In addition, is

3Q their multiplication quickly. You can also be viewed as indicators of virus contamination.

Experiment description;

gg The phages were determined in three stages of the adsorption / elution cycle:
a) immediately after the sample, which covers the sheaths of the deep

contains erythrocyte cells that have been inoculated with the virus / phage system;

b) deducted from the projecting phase (above measure 2) at pH 3.5, after centrifugation, and

c) taken after measure 3 at a pH of about 7.5 after the KPP solution to the precipitation given and homogeneously dispersed.

At the same time, a control experiment was carried out in parallel with phages in the saline solution without animal erythrocyte cell envelopes. All experiments were carried out in a saline solution to protect the bacteriophage from the osmotic shock they would receive in hypotonic solutions. The results compiled in the tables are expressed as percentages by weight and were calculated as follows:
The phage count in measure 1 with the indication "a represents 0% adsorption and is denoted by the following formula:

"a"

100 - (^ J), while eluting by the formula

cx100

is reproduced, where b is the phage number in

^a

the remaining phase in measure 2 and c the

Phage number in the measure suspension is 3. The results given in the tables of the following examples were determined using the above formulas.
30th

example 1

Two mixtures of envelopes from erythrocyte cells (15%) (from pigs) in the form of a membrane, each in 5 ml of distilled water and in 5 ml of a saline solution ". (0.85%), were for the adsorption / elution cycle used by three bacteriophages, namely «Sx-174, MS-2 and f2 in infected water. The results are

those shown in the following Table 1 together with those in which a beef extract (3% by weight) and a saline solution were used as controls became.

10

15th

30th 35

Table 1

(Adsorption and elution of phages using beef extract from different origins, compared with erythrocyte membranes)

Phage PFU / ml OXOID
PROD.
INOLEX.
PROD.
DIFCO
PROD. 0X-174 7.0 3.5 7.0 %
Ads. %
EIu. MS-2 7.0 3.5 7.0 %
Ads. %
Iu. f-2 7.0 3.5 7.0 %
Ads. %
EIu. > v PH
Adsor-N.
bens N. in cook
salzlo
sung
0.85% 3.3x10 ²
3.4xlO ²
3.2x10 ² 0.4x10
3.4xlO ²
4.4xlO ² 3.4x10 ²
3.2xlO ²
2.7xlO ² 98.8
66
0 103
94
84 1.4x1O ³
1.4xlO ³
1.5x1O ³ 1.2xlO ³
1.3x10 ³
1.4xl0 ³ 1.3x10 ³
1.4xlO ³
1.3x1O ³ 14.3
7.2
6.7 93
100
36.6 XlO ⁴
1.2XlO ⁴
1.5x10 ⁴ 4.5x10 ³
1.2xlO ⁴
6xlO ³ 5.7xlO ³
9.5xlO ³
9.2xlO ³ 55
0
60 57
79
61 (3%) beef extra. in
least.
water 3.9xlO ² 0.6x10 4x10 ² 98.5 102 1.35xlO ³ 0 1.3xlO ³ 100 ) 6. 1.2XlO ⁴ 0 l.lxlO ⁴ 100 92 (15%) cases Saline solution 4.2xlO ² 0.6x10 5.3x10 ² 98.6 126 1.37xlO ³ 0 1.35x10 ³ 100 98 L.2x10 0 1.3xl0 ⁴ 100 108 4.9xlO ² 4.7xlO ² 4.9xlO ² 4.5 100 1.32xlO ³ 1.3xlO ³ 1.3xlO ³ 1.5 98 L.2x1 $ 1.2xlO ⁴ l.lxlO ⁴ 0 92

The following can be drawn from the results given in Table 1 above:

(1) the adsorption and elution efficiency is im essentially 100% for all of the above phage, be it in saline or in distilled water, whatever is not the case for the 3% beef extract.

(2) The effectiveness of adsorption and elution is determined by the pH (in the range of 3.5 to 7.0) im Contrary to the results obtained with the 3% beef extract, not affected.

(3) The effectiveness of adsorption and elution obtained with the 3% beef extract, is strongly dependent on the origin of the beef extract, which does not apply to the method according to the invention, uses the sheaths of animal erythrocyte cells.

Example 2
A 13% (volume) mixture of envelopes of porcine erythrocyte cells in the form of a membrane and in 5 ml of a saline solution (0.85%) was used to adsorb and elute the poliovirus LSC-1 strain, respectively. The results are as follows Table 2 compiled. It is compared with the results obtained with a 3% beef extract solution of various origins and a saline solution as a control.

Table 2

(Adsorption and elution of the poliovirus using erythrocyte membranes (13%) and beef extract (3%) from three different origins / virus type Poliovirus LSC-I (PFU / ml))

Adsorption matrix
pH

Erythrocyte membrane

INOLEX

Beef extract (3%)

DIFCO OXOID

Saline solution (control)

7.0
3.5
7.0

2.1x10

4b

1.9x10 '

1.9x10 "

0.6x10

1.6x10

2.0x10 '1.8x10 0.2x10

2.1x10 '

0.8x1O ³

1.6x10 '

4.IxIO ³ 3.7xlO ³ 5.5xlO ³

Adsorption(%) 100 97 12th 96 9.8 Elution Ci) 90 82 10 76 134

Note: 13% erythrocyte membrane (in a saline solution)
a - PFU; Plaque-forming unit
b - Results are averages of two trials

The same conclusions drawn in connection with the results of Table 1 also appear to apply to the results of Table 2: the adsorption and the elution depend strongly on the origin of beef extract (3%), while at Use of the method according to the invention in which the different phages are essentially constant.

Example 3

Various attempts have been made with the adsorption / elution cycles using three bacteriophages by means of the method according to the invention in three Temperatures carried out, namely at 4, 24 and 37 ° C. The results are summarized in the following table 3

15 posed.

Table 3
(Adsorption and elution of batches with erythrocyte membranes at different temperatures)

Phages
PPU / ml 0X-174 24 ° C 7 ⁰ C Saline solution 24 ⁰ C 37 ⁰ C MS-2 24 ⁰ C 37 ° C Saline solution 24 ⁰ C 37 ⁰ C f 2 Erythrocyte
membrane 24 ° C 37 ⁰ C Saline solution
PFU / ml > 4 ° C 37 ⁰ C Adsorb.
material Erythrocyte
membrane 6.2
xlO
0
5.3
xlO ^6X 4
ίο ⁴
0
3.4
KlO ⁴ 4 ⁰ C 6.6
xlO
^6Λ 4
xlO
⁶ ' ³ 4
xlO 7.S ₄
xlO
6 · 1 ₄
xlO
1 9 ₄
xlO Erythrocyte
membrane 5.2 ₄
xlO
3.6
xlO ³
3.3
xlO 5.2
xlO
2x
10 ³
4-9 ₄
xlO 4 ° C 5-9 ₄
xlO
5-2 ₄
xlO
4-9 ₄
xlO 5.3 ₄
xlO ⁴
5.6 ₄
xlO
^{4 6} 4
xlO 4 ° C 7-5 ₄
xlO
Ix
10 ^{3
6 3} 4
xlO 8.5
xlO
2x
10 ³
6.7 ₄
xlO 4 ° C 7.2 ₄
xlO
6.2
xlO
⁷ ^ ₄
xlO 8.2
xlO
4 4 ₄
xlO
6.5
xlO ^ * \ Temp
pH ^ C. 4 ° C 100 100 ⁵ ' ⁷ 4
xlO
5.1
xlO
6 · 4 ₄
xlO 7.6 18.7 4 ° C 93 96 3-8 ₄
xlO
3.8
xlO ⁴
3.3
xlO 12th 0 8.6
xlO
4x
10 ³
6.2
xlO 98.7 97.7 ⁸ ^ ₄
xlO
4.5
xlO
6.5 ₄
xlO 14th 47 7.0
3.5
7.0 5-8 ₄
xlO
0
5-8 ₄
xlO 85 56 10.6 97 84 3-7 ₄
xlO ⁴
7.6
xlO ³
3.9 ₄
xlO 77 75 0 83 87 95 84 79 44.5 98.6 79 (%) (C)
Adsorp. 100 89 79.5 87 72 80 (%)
Elution 100 51

Note: The erythrocyte membrane concentration of the experiments was 13% (in the saline solution) at 24 ° C.
Each experiment was carried out twice and the average was determined.

CT <OO

From the above results, it is clear that in the temperature range of 4 to 37 ° C, those with the The adsorption / elution results obtained in the process according to the invention are essentially constant,

5 which does not apply to the case of saline solutions.

Example 4

A trial was made using different concentrations the shells of animal erythrocyte cells.

The adsorption-ZElution cycles were with three bacteriophages performed, namely jox-174, MS-2 and f2. Here, the shells of animal erythrocyte cells of the given concentration were placed in a saline solution (0.35% / Volume) at a constant pH of 3.5. The results are in the table below 4 compiled.

The results show that the adsorption efficiency at concentrations in the range of 4 to 32% (Volume) is in the range of 78.8 to 100%.

Table 4
(Adsorption of the phargen at different erythrocyte membrane concentrations, pH 3.5)

Phage
PFU / ml tfx-174 Phage
Titer ^a Phage
titer % (C)
has. MS-2 Membrane-
concentra-
tion (%) Phage
Titer ^a Phage
b
Titer %
has. f2 membrane
concentra
tion (%) Phage
Titer Phage
b
Titer %
^ ds. membrane
concentra
tion (%) 4.6x1O ⁶
3xl0 ⁸
7.2x1O ⁶
1.2x1O ⁷
7.2x1O ⁸
8x10 ⁸
2.5xlO ⁷
1.3xlO ⁹ 1.2xlO ⁸
5.2x1O ⁹
1.2X10 ⁸
L.2xlO ⁸
S.2xlO ⁹
S.2xlO ⁹
L.2xlO ⁸
i.2xlO ⁹ 96
94
94
90
86
84.6
79
75 26th
18th
12th
4th
1 2.5x10 ⁶
2.6xlO ⁶
3.IxIO ⁶
IxIO ⁷
3.8xlO ⁷ 4.7xlO ⁷
4.7xlO ⁷
4.5xlO ⁷
4.7xl0 ⁷
4.4xlO ⁷ 95
94
93
78.8
14th 26th
12th
4th
2
0.9 0
6x10 ²
L.3xlO ³
l.6xl0 ³
i.6xlO ³ 1.2xlO ⁴
1.2xlO ⁴
IxIO ⁴
1.2xlO ⁴
1.4xlO ⁴ 100
95
87
62
53 32
26th
23
11th
5
3
2
<0.5

Note: a - phage titer in the supernatant phase with erythrocyte membranes (measure 2,

pH 3.5);
b - Phage titer in a saline solution without an erythrocyte membrane (measure 2, pH value 3.5)

1 example 5

Some attempts have been made using the process of the invention with the adsorption-elution cycle performed on a biological fluid in the form of urine. The following strains of virus were determined: Poliovirus LSC-1, Echovirus 6, Echovirus 7 and Coxsackievirus B 5. 5 ml of urine were via a Membrane with 15% (volume) envelopes of porcine erythrocyte cells (experiment A), prepared according to the above Description, headed. Furthermore, comparative tests were carried out, also using 5 ml of urine, carried out with the envelopes of the porcine erythrocyte cells (Experiment B) under the same conditions as in Experiment A. the Results of the adsorption / elution cycle are shown in Table 5 below.

Table 5

Poliovirus Echovirus 6 Echovirus 7 Cocksackievirus B5

% Ads. % EIu. % Ads. % EIu. % Ads. % EIu. % Ads. % EIu.

A 98.6 111 96.4 101 93.5 79.7 78 84

B 59 97 2.7 97.3 8 102 5.6 97.2

° The above results clearly show the beneficial ones

Effect obtained by using a membrane with the sheaths of porcine erythrocyte cells. The effectiveness the adsorption / elution cycle for viruses from the

Urine is essentially 100%. 35

1 example 6

Some attempts have been made using the method of the invention with other biological fluids performed, namely with a cerebrospinal fluid . In the experiments, 5 ml of this liquid was in a membrane with 15% (volume) porcine erythrocyte cell envelopes (Experiment A), prepared according to the information in the above description, used. Comparative tests were carried out without the membrane (test B), produced under the same conditions, carried out. The results of the adsorption / elution cycle are given in Table 6 below.

15 Table 6

(Adsorption / elution of LSC-I
% EIu. Cerebrospinal fluid viruses) 6th
EIu. (zSx-174
% Ads (Bacteriophage)
% EIu. 20th Poliovirus
% Ads. 100
104 Echovirus
% Ads. % 114
118 98.9
0 102
111 A 91.7
B 7 98.2
0 25th Example 7

The following Table 7 shows the results of an adsorption / elution carried out using a Membrane with 15% (volume) porcine erythrocyte cell envelopes indicated, with the in a saline solution The following viruses present were determined: Echovirus 7, Coxsackia virus B-5, Echovirus 6, rotavirus (SA-11) and Poliovirus LSC-1).

Echovirus 7 100 100 100 160 Table 7 Echovirus 6th Rotavirus 88 (SA-Il) Attempt Adsorbed Eluted Adsorbed Eluted 99 91 100 105 Adsorbed Eluted Adsorbed 96 Eluted 1 100 104 100 120 94 91 95 92 2 17.5 109 13.4 86.6 100 104 8th 92 3 100 114 108 4 (con
trolls) five incoming viruses on erythrocyte cell envelopes)
% Virus 18.2 82 116 Coxsackievirus B5 (Adsorption / elution of Adsorbed Eluted Poliovirus LSC-I 100 100 100 104 100 108 8.2 71

Note : The volume tested was 5 ml of a saline solution containing 13% erythrocyte cell envelopes (experiments 1 to
3) and a saline solution alone (experiment 4). The virus titers were 1.6x10 to 3.1x10
PFU / ml. Elution was carried out as described in connection with the Materials and Methods.

~ ²³ ~ 351353c

1 example 8

An experiment was made using a column (10 cm high) connected to agarose with hexylamine groups ( with cyanogen bromide) and envelopes of erythrocyte cells. The particular virus was OxI The results obtained can be found in Table 8 below.

10 Table 8

Experiment number adsorption (%) elution

1 75 94

2 82 90

3 (control without 18 98 20 envelopes of

Erythrocyte cell)

From the values in the above table it is clear that experiment 3 (control experiment without erythrocyte cell envelopes) shows a very poor adsorption, while in the method according to the invention an almost complete one Adsorption and elution appear.

The invention can also be used with great success in connection with known test systems which are used for the determination of viruses can be used. This combination aims to increase the sensitivity of the respective test system. The Elisa test system for the determination of rotavirus (manufactured by Dakopatts, Denmark), with which the determination of the rotavirus antigen with concentra-

ORiGiNAL INSPECTED

tions above 10 PFU (plaque-forming unit) per 100 ml can be detected. At concentrations below 10 PFU / ml, the sensitivity of the detection of the rotavirus is very poor. Using the virus concentration according to the present invention before using the Elisa test system, concentrations that were originally below 10 and even below 10 PFU / ml can be determined with the highest accuracy. The following table 9 shows results which were obtained when the rotavirus SA-11 (from monkeys) was determined using the Elisa test system. The sample had a concentration below 10 PFU / ml. A dilution to 10 PFU / ml was carried out. The determination was Erten at two pH ~ T ^"T, ie, at 3.5 and 7.2, is performed (Serial No. 1 and 2 with concentration;. 3 and 4 without concentration).

Table 9

Serial no. ph trial number control number

1 3.5 ³⁰ 2 7.2

3 3. ¹ p

4 7.2 35

The results of Table 8 above show that the concentration according to the present invention leads to positive determinations with the Elisa test system at a pH value of 7.2, while without

5 the concentration could not be detected.

Claims (15)

GEYER, HAGEMANN & KEML PATENTANWÄLTE EUROPEAN PATENT ATTORNEVj ^ naninger Strasse 108 8000 Munich 80 Telephone D 089/98 07 31-34 Telex 5216136 hage d Telegram: hageypatent Telefax 089/98 24 21 Automat (CCITT Gr. 2) Postal address: PO Box 860329 ■ 8000 Munich 86 Technion Research & Munich, the Development Foundation Ltd, May 23, 1985 Haifa, Israel Dr.H / 3 / cw uZ: Pat 77 / 3-85Ch patent claims 1. Method of concentrating viruses from liquid Waste and biological fluids, characterized in that * a) the liquids containing viruses are brought into contact with an adsorbing matrix containing the shells of animal erythrocytes ^{A cells,} b) the matrix obtained according to measure (a) is acidified, whereby the on the shells of the animal erythrocyte cells' adsorbed precipitate is separated from viruses, c) the precipitate obtained after measure (b) with a solution is eluted which has a pH value above that prevailing in measure (b), and d) a concentrate of viruses is obtained. 2. The method according to claim 1, characterized in that the elution in measure (c) with a buffer solution a pH above 6.5 is carried out. 3. The method according to claim 1 or 2, characterized in that that the adsorbent matrix is in the form of a continuous film. 4. The method according to claim 3, characterized in that that the film is in the form of a membrane. 5. The method according to claim 1 or 2, characterized in that that the adsorbent matrix in the form 10 of a particulate solid material is present. 6. The method according to claim 5, characterized in that the particle size of the solid material is between 1 and 20 ^ m. 7. The method according to any one of claims 1 to 6, characterized in that the concentration of the casings of the animal erythrocyte cells in the adsorbing matrix is between 4 and 30% by volume. 8. The method according to any one of claims 1 to 7, characterized in that it is carried out at a temperature between 4 and 37 ° C. 9. The method according to claim 5 or 6, characterized in that the shells of the animal erythrocyte cells can be applied to a carrier. 10. The method according to claim 9, characterized in that the carrier is glass beads or plastic beads used. 11. The method according to any one of claims 1 to 10, characterized in that the microbial spoilage the shells of the animal erythrocyte cells are prevented by treatment with a preservative. 12. The method according to claim 11, characterized in that 1 that the preservative is sodium azide. 13. The method according to any one of claims 1 to 11, characterized in that the biological fluids 5 fluid urine is used. 14. The method according to any one of claims 1 to 11, characterized in that the biological liquid uses a cerebrospinal fluid 10 will. 15. The method according to any one of claims 1 to 14, characterized in that this in conjunction with a Test system used to determine viruses 15 is carried out.