RU2269134C2 - Method for prognosis of acute viral hepatitis c finish - Google Patents

Abstract

FIELD: medicine, clinical virology.

SUBSTANCE: method involves assay of antibodies raised against some antigen sites of two surface proteins (E1 and E2) by using the following 5 synthetic peptides as antigens: 1) NH₂-SGHRMAWDMMMNWSP-CONH₂; 2) NH₂-STLTSLPTPGASG-CONH₂; 3) NH₂-RPYAWHYAPRPAGIVPASQV-CONH₂; 4) NH-TTDRIFGAPTYSWGENETDVL-CONH₂; 5) NH₂-TWIMNSTGFTKTAGGPPANIGGVGNNT-CONH₂. The favorable finish of disease is prognosticated by detection of antibodies for the first 3-4 weeks of disease. The advantage of the invention involves the prognosis for the disease finish in the early stage of disease. Invention can be used in clinics of infectious diseases for aims of early prognosis of acute hepatitis C finish.

EFFECT: improved method for prognosis of hepatitis C.

6 tbl, 3 ex

Description

The invention relates to medicine, more specifically to clinical virology, and may find application in the clinic of infectious diseases for early prognosis of acute hepatitis C.

Known publication (Zibert A., Meisel H., Kraas W. et al. Early antibody response against hypervariable region 1 is associated with acute self-limiting infections of acute Hepatitis C virus.// Hepatology 1997; 25: 1245-1249), in which the authors determined antibodies to the hypervariable region 1 (HGR-1) of the hepatitis C virus surface E2 protein in patients infected with hepatitis C virus of genovariant 1b, and found that, in patients with a favorable disease outcome (recovery), antibodies to this region were found in 43% of cases in the first 6 months after infection, while in patients with an unfavorable outcome in chronic Orm such antibodies in a specified time detected only in 13% of cases. Based on the data obtained, the authors conclude the importance of determining antibodies to HVR-1 to predict the outcome of the disease.

However, examination of patients to determine antibodies at such late dates (6 months or more) cannot satisfy the clinic of infectious diseases, which requires earlier prognostic criteria for the outcome of the disease in order to use timely adequate therapeutic measures. In addition, to determine antibodies to the surface proteins of the HS virus, the authors used only one fairly short fragment of the protein from HHR-1 as an antigen, while there are several more antigenic determinants in the area of two surface proteins of the virus E1 and E2, the use of which could significantly increase the frequency of detection of antibodies and increase the reliability of the prognosis of the outcome of the disease. The invention is aimed at developing a method for predicting the outcome of acute hepatitis C by determining antibodies to several antigenic sites of two surface proteins (E1 and E2) using 5 synthetic peptides as antigens. The purpose of the invention is the forecast of outcomes of acute hepatitis C at an early stage of the disease and increase the reliability of the prognosis.

It was shown that in patients infected not only with the genovariant. 1b, but also with the 3a genovariant (the most common virus genovariants in the world), with a favorable outcome of the disease (recovery), antibodies to all 5 antigenic determinants of surface proteins are detected in the first 7 weeks of the disease, i.e., in the early stages of the infection process. In patients with a chronic chronic disease outcome, antibodies to surface proteins are not detected in the first 7 weeks in most cases. Thus, early detection of antibodies to the antigenic determinants of the surface proteins E1 and E2 within 7 weeks of the onset of the disease allows a favorable outcome to be predicted.

Antibodies to surface proteins are determined by enzyme immunoassay. To detect antibodies in serum, it is necessary to ensure contact of the test serum with the antigen and conjugate. Detection of antibodies to surface proteins is carried out due to their interaction with specific synthetic peptides adsorbed on the surface of the polystyrene microplate wells. The resulting antigen-antibody complex is detected using a conjugate based on monoclonal antibodies against human Ig G after adding a substrate solution.

As antigens, 5 synthetic peptides of the following structure are used:

1. NH ₂ -SGHRMAWDMMMNWSP-CONH ₂

2. NH ₂ -STLTSLPTPGASG-CONH ₂

3. NH ₂ -RPYAWHYAPRPAGIVPASQV-CONH ₂

4. NH ₂ -TTDRIFGAPTYSWGENETDVL-CONH ₂

5. NH ₂ -TWIMNSTGFTKTAGGPPANIGGVGNNT-CONH ₂

All peptides correspond to the putative antigenic determinants of the surface proteins E1 and E2 of hepatitis C.

The specificity of the reaction of these antigenic sites of the viral protein with sera containing and not containing antibodies to hepatitis C virus (anti-HCV) was evaluated in enzyme-linked immunosorbent assay (ELISA) using certified in commercial Russian and foreign screening (Aquagep C, Monolisa HCV, Immunocomb HCV ) and confirmatory tests (LiaTek HCV, Wellcozyme HCV immunoblot) of serum panels.

The authors found that all synthesized peptide fragments of the hepatitis C virus polyprotein specifically react with anti-HCV-positive sera.

The specificity of the reaction of synthetic peptides-analogues of antigenic determinants of surface proteins was evaluated by the following parameters:

- the absence of cross-reactions with IgG antibodies to the hepatitis B virus nuclear protein, to hepatitis A virus;

- lack of reaction with blood serum of anti-HCV-negative infectious patients etiologically not related to hepatitis viruses (HIV-infected);

- lack of reaction with blood serum of anti-HCV-negative blood donors;

- the presence of a reaction with the blood sera of patients with chronic hepatitis C infected with different virus genovariants containing total anti-HCV according to commercial tests.

The prognostic value of detecting antibodies to surface proteins of hepatitis C virus was assessed by the frequency of detection of these antibodies in patients with acute hepatitis C at different stages of the disease in comparison with the detection of specific hepatitis C virus RNA in blood serum at the same time intervals. A complete normalization of clinical and biochemical parameters and the absence of virus RNA in the blood serum 50-60 weeks after the onset of the first symptoms of the disease were taken for a favorable outcome (recovery). Adverse development of the disease with the formation of a chronic infection was characterized by the presence of virus RNA in serum 50-60 weeks after the onset of the disease and an increased level of alanine aminotransferase. The invention is implemented as follows. To detect antibodies to surface proteins, an immunosorbent was used, which is a polystyrene microplate, the wells of individual strips of which are coated with synthetic peptides:

1. NH ₂ -SGHRMAWDMMMNWSP-CONH ₂

2. NH ₂ -STLTSLPTPGASG-CONH ₂

3. NH ₂ -RPYAWHYAPRPAGIVPASQV-CONH ₂

4. NH ₂ -TTDRIFGAPTYSWGENETDVL-CONH ₂

5. NH ₂ -TWIMNSTGFTKTAGGPPANIGGVGNNT-CONH ₂

Source: peptide No. 1 - surface protein E1 of hepatitis C virus, fragment 314-328; peptides No. 2, 3, 4, 5 — hepatitis C virus surface E2 protein, fragments 397-411, 483-502, 514-531, 553-578, respectively. The claimed peptides are obtained by the solid-phase method with sequential peptide chain growth on a copolymer of styrene with 1% divinylbenzene, the α-amino groups of amino acids are blocked by tert-butyloxycarbonyl groups. The following groups are used to protect the side radicals of trifunctional amino acids: for lysine, 2-chlorobenzyloxycarbonyl; for histidine tosyl; for threonine, glutamic acid, the corresponding benzyl esters; for aspartic acid, cyclohexyl ether; for arginine - mesitylenesulfonyl; for tyrosine - 2,6-dichlorobenzyl. For condensation, dicyclohexylcarbodiimide or dicyclohexylcarbodiimide with the addition of 1-hydroxybenzotriazole is used. The release is carried out using a 50% solution of trifluoroacetic acid in CH ₂ Cl ₂ medium, and neutralization with a 5% solution of diisopropylamine in CH ₂ Cl ₂ . Cleavage of the obtained peptides from the polymer and the release of the side protective groups are carried out using HF, and purified by gel and reverse phase chromatography. The solid-phase method for producing peptides is described by Barany G., Merrifield RB, Solid-phase peptide synthesis. In: Peptides. Analysis, Synthesis, Biology. Eds .: Gross E., Meienhofer J., NY- Academic Press.- 1980. - vol. 2 - p. 3-285 /

Example 1. For the synthesis of one peptide of the above formulas, 0.5 g of benzhydrylaminopolymer is loaded into the reaction vessel. The amino group content is 1 mM / g polymer. The peptide chain is further expanded according to the following program (for the addition of one amino acid, see table 1).

If the ninhydrin test is positive, the condensation is repeated starting from step 5. In the case of a negative test result, the next amino acid residue is attached, passing through the program from claim 1. Upon completion of the synthesis, the peptidyl polymer is dried in a vacuum desiccator over phosphorus pentoxide to constant weight. Yield 2.4 g (60% of theory). 1 g of the peptidyl polymer is transferred to the reactor of the plant for working with liquid hydrogen fluoride, 0.5 ml of thioanisole and 0.5 ml of meta-cresol are added, cooled to a temperature of -78 ° C and 10 ml of anhydrous hydrogen fluoride are distilled for 10 minutes. The reaction mixture was heated to 0 ° C and stirred for 90 minutes, then hydrogen fluoride was distilled off. The residue was transferred to a Schott filter and washed with ethyl acetate and ether. The peptide is extracted with 50 ml of 25% acetic acid, diluted with water and lyophilized. The output from 1 g of peptidyl polymer is 135 mg (59%). After desalting on a Sephadex G-10 column (eluent 50% acetic acid), the product is purified on an Altech Rsil C 18 column in 0.1% trifluoroacetic acid in a gradient of 20-50% acetonitrile. Fractions containing the peptide are collected and lyophilized. The purified peptide is individual according to high performance liquid chromatography (Delta PAKC column 18.5 0.4 15.0 cm, flow rate 1 ml / min, eluent 0.1% trifluoroacetic acid, gradient 20-50% acetonitrile). Retention time 8.44 minutes The data of amino acid analysis of peptide hydrolysates showed their full compliance with theoretically calculated parameters.

Example 2. Enzyme-linked immunosorbent assay and assessment of the specificity of the reaction of peptides with the studied sera.

The assessment of the specificity of the reaction of peptides with the studied sera was carried out in enzyme-linked immunosorbent assay (ELISA). The ELISA technique provides for the presence of an immunosorbent. To obtain it, each synthesized peptide was dissolved to a concentration of 1 μg / ml in standard carbonate-bicarbonate buffer solution (BCF) with a pH of 9.5. The resulting solutions were introduced into a separate for each peptide polystyrene microplate with a high adsorption capacity of the Biohit brand (Finland), 120 μl in all wells and incubated for 18-24 hours at a temperature of + 2-8 ° C. After incubation, the solution from the wells was removed, and the microplates were dried at room temperature, sealed in plastic bags and stored at a temperature of + 2-8 ° C until use.

Since there are no special certified serum panels containing antibodies to the surface proteins of the hepatitis C virus, it was necessary to establish how the blood serum obtained from 90 absolutely healthy blood donors and not containing anti-HCV according to commercial screening test systems manufactured by Aquapast "(Russia, St. Petersburg) and Orgenics (Israel), with prepared immunosorbents. The study of these samples of blood serum in ELISA was performed as follows:

1. Hydration of adsorbed antigen. All wells of the microplate with adsorbed antigen are filled to the brim with standard phosphate-buffered saline (FSF) pH 7.5, and then the solution is removed by pump. The procedure is performed 1 time.

2. Binding of antibodies. One of the wells (A1) is left blank (substrate control). 90 μl of SDF and 10 μl of test samples were added to all other wells, receiving a 10-fold dilution of the test sample. The microplate is closed with a lid and incubated at a temperature of 37 ± 1 ° C for 1 hour in a humid chamber. After incubation, the wells are washed with FSR 3 times.

3. Attachment of the conjugate. 100 μl of conjugate solution (monoclonal antibodies against human IgG labeled with peroxidase) was added to all wells except A1. The microplate is closed with a lid and incubated at a temperature of 37 ± 1 ° C for 1 hour in a humid chamber. After incubation, the wells are washed 5 times with SDF.

4. Conducting an enzymatic reaction. 100 μl of substrate solution are added to all wells. The tablet is closed with a lid and kept in the dark at room temperature for 15 ± 1 min in a humid chamber.

5. Stopping the enzymatic reaction. The reaction is stopped by adding 50 μl of a solution of sulfuric acid to each well.

6. Instrumental accounting of results. The measurement of optical density (OD) is carried out at a wavelength of 490 nm directly in the wells of microplates using vertical photometers. Well A1 serves as a comparison cuvette with substrate control.

A study of 90 sera from healthy blood donors showed that all immunosorbents showed very weak background reactions, not exceeding 0.2 optical units. This led to the use of a pool of sera from healthy donors as a negative control sample in subsequent experiments to evaluate the specificity of peptides on different serum panels. In all subsequent experiments, the following changes were made to the ELISA:

1. At the stage of antibody binding, 10 μl of a negative control sample, a pool of sera from healthy donors, is added to 3 wells (B1, C1, D1).

2. At the stage of instrumental accounting of results. A quantitative assessment of the results of ELISA is carried out according to the formula:

K = Average OD in wells with negative samples × 2.1

If the OD of the test sample is greater than K, then it is considered to be reactive with the immunosorbent (containing antibodies to the adsorbed antigen). If the OD of the test sample is less than or equal to K, then it is considered not to react with the immunosorbent (not containing antibodies to the adsorbed antigen).

The specificity of immunosorbents was evaluated on serum panels certified using commercial test systems containing IgG antibodies to the hepatitis B virus nuclear protein (45 sera), to hepatitis A virus (57 sera), to human immunodeficiency virus (86 sera), to the virus hepatitis C (30 sera). The last group of sera was obtained from patients with chronic hepatitis C. The results of the studies are summarized in table 2. All immunosorbents did not react with sera containing antibodies to hepatitis B virus, hepatitis A virus, and human immunodeficiency virus. At the same time, all immunosorbents reacted with sera from patients with chronic hepatitis C with a frequency of 61.3% (peptide 3 E2 483-502) to 83.9% (peptide 5 E2 553-578). It was noted that immunosorbents almost equally often reacted with both the sera of patients infected with genovariant 1b and genovariant 3a (table 3). This suggests that all peptides - analogues of antigenic determinants of the surface proteins of the hepatitis C virus, specifically react only with sera from patients with hepatitis C, moreover, infected with two different genovariants.

Example 3. Assessment of prognostic value. 21 patients with an established diagnosis of acute hepatitis C were monitored. The diagnosis was based on the following criteria: detection of anti-HCV in ELISA, detection of HS virus RNA in the polymerase chain reaction (PCR), increase in serum alanine aminotransferase (AlAt) by 5 times or more compared to normal (40 ME); test results for markers of hepatitis B virus (HBsAg, anti-HBc IgM) and hepatitis A virus (anti-HAV IgM) are negative. The average AlAt level in patients upon admission was 706.3 ME. The monitoring program included determining the dynamics of anti-HCV, HS virus RNA, antibodies to surface proteins of the HS virus, and AlAt level.

The determination of antibodies to surface proteins showed that already at 2-3 weeks after the onset of the disease, they were present in 38.8-61.1% of the examined, depending on the immunosorbent used (see table 4). The detection rate of these antibodies increased over time and reached its highest values at the end of the observation (on average 56 weeks after the onset of the disease). In this case, antibodies were detected in 66.7-91.7% of cases. Long-term laboratory observation results were available for evaluation in 12 patients. Of these 12 people, 5 had a recovery, and 7 - the development of a chronic infectious process. In the analysis of the immune response to the antigenic determinants of the surface proteins of the HS virus, significant differences were found in these 2 groups.In the group with a favorable outcome of the disease, all patients already at 3-7 weeks showed antibodies to almost all antigenic determinants represented by the corresponding synthetic peptides ( table 5). The exception was 1 patient, at the beginning of the disease, antibodies to antigenic determinants 4 and 5 were not detected. During the observation process, all RNA of the virus stopped detecting the RNA of the virus in the final examination conducted at 45-63 weeks after the onset of the disease (average 57 week) test for RNA was negative. All patients fully normalized biochemical parameters. It should be noted that in all patients the dynamics of a decrease in the quantitative content of antibodies to surface proteins was observed, and in two out of 5 these antibodies generally ceased to be detected at the final stage of observation. When assessing the level of total antibodies to hepatitis C virus (anti-HCV), there was also a dynamics to a significant decrease - the ratio of OD / K at the beginning of the observation was 4.48, and at the end of the observation - 2.18. This indicates the absence of antigenic irritation associated with the reproduction of the virus and the formation of viral proteins, and the extinction of the immune response, which indicates the cleansing of the body from the virus, and therefore, recovery.

A different picture of antibody production was established in the group of patients with an unfavorable outcome of the disease with the formation of a chronic infection. In 4 out of 7 people of this group, antibodies to surface proteins were not detected at 3-7 weeks (table 6). Their appearance was recorded much later, and at the end of the observation (on average 57 weeks) they were detected in 6 out of 7 examined. In 1 patient, antibodies to surface proteins did not appear within 62 weeks of observation.

HS virus RNA was constantly detected in all patients, including at the final stage of observation (57 weeks). This indicates ongoing reproduction of the virus, and therefore, ongoing antigen irritation. This is also indicated by a dynamic increase in the level of total anti-HCV in the examined group. At the beginning of the observation, the average OD / k was 4.1, and at the end of the observation, 7.1. In addition, it should be noted that in all patients of this group, periodic increases in AlAt levels were observed, which also indicates continued damage to the liver cells. Thus, the early appearance of antibodies to the surface proteins of the HS virus helps to cleanse the body of the virus and recover. The definition of these antibodies in clinical practice allows us to predict the outcome of the disease.

Table number 1
The program of joining one amino acid residue No. Operation Reagents Repeatability Time (min) Reagent Volume
(ml) one Release 50% trifluoroacetic acid in methylene chloride 2 2
thirty fifty
fifty 2 Flushing Methylene chloride 6 2 80 3 Neutralization 5% diisopropylethylamine in methylene chloride 3 2 fifty four Flushing Methylene chloride 6 2 80 5 Condensation A solution of an amino acid derivative, dicyclohexylcarbodiimide and 1-hydroxybenzotriazole in a mixture of dimethylacetamide and methylene chloride one 120 35 6 Flushing Dimethylacetamide 2 2 80 7 Flushing Isopropanol 3 2 80 8 Flushing Methylene chloride 3 one 80 9 Ninhydrin test - - - -

Table 2.
The frequency of response of serums containing antibodies to certain viral antigens with immunosorbents based on peptides corresponding to antigenic determinants of the surface proteins of hepatitis C virus. Serum group amount The frequency of positive reactions with immunosorbents based on peptides from the surface protein region 1 (E1 314-328) 2 (E2 397-411) 3 (E2 483-502) 4 (E2 514-531) 5 (E2 553-578) abs % abs % abs % abs % abs % With IgG antibodies to HBV nuclear protein (anti-HBc) 45 0 - 0 - 0 - 0 - 0 - With IgG antibodies to hepatitis A virus (anti-HAV) 57 0 - 0 - 0 - 0 - 0 - With IgG antibodies to human immunodeficiency virus (anti-HIV) 86 0 - 0 - 0 - 0 - 0 - With IgG antibodies to hepatitis C virus (anti-HCV) thirty 21 67.7 25 80.6 19 61.3 24 77.4 26 83.9

Table 3
The frequency of response in the enzyme immunoassay of synthetic peptides corresponding to the antigenic determinants of the surface proteins of the hepatitis C virus, with sera of patients with chronic hepatitis C infected with the genotypes of the HCV-1b and HCV-3a virus Hepatitis C virus genotype The number of patients examined Anti-HCV The frequency of reaction with peptides E1-1 *
(314-328) E2-2
(397-411) E2-3
(483-502) E2-4
(514-531) E2-5
(553-578) HCV-1 24 24 / 100.0 16 / 66.7 ** 19 / 79.2 14 / 58.3 18 / 75.0 20 / 83.3 HCV-3 7 7 / 100.0 5 / 71.4 6 / 85.7 5 / 71.4 6 / 85.7 6 / 85.7 Total 31 31 / 100.0 21 / 67.7 25 / 80.6 19 / 61.3 24 / 77.4 26 / 83.9 * - the name of the peptides corresponding to the proteins of the hepatitis C virus: E1 - surface protein 1, E2 - surface protein 2. The positions of the synthesized sections of the virus proteins by amino acid sequence are shown in parentheses
** - in the numerator - the number of positive samples / in the denominator - the proportion of positive samples in%

Table 4
The frequency of response in an enzyme-linked immunosorbent assay of synthetic peptides corresponding to the antigenic determinants of the surface proteins of the hepatitis C virus, with the blood serum of patients with acute hepatitis C, obtained at different stages of the disease Testing terms from the onset of the disease (in weeks) The number of patients examined anti-HCV The frequency of reaction with peptides E1-1 *
(314-328) E2-2
(397-411) E2-3
(483-502) E2-4
(514-531) E2-5
(553-578) 2-3 eighteen 18 / 100.0 11 / 61.1 ** 7 / 38.8 11 / 61.1 11 / 61.1 9 / 50.0 4-6 fifteen 15 / 100.0 10 / 66.7 7 / 46.7 7 / 46.7 10 / 66.7 12 / 80.0 7-9 eleven 11 / 100.0 9 / 81.8 6 / 54.5 7 / 63.6 8 / 72.7 9 / 81.8 10-26 fifteen 15 / 100.0 12 / 80.0 6 / 40.0 7 / 46.7 12 / 80.0 11 / 73.3 26-66 12 12 / 100.0 9 / 75.0 9 / 75.0 8 / 66.7 11 / 91.7 10 / 83.3 * - the name of the peptides corresponding to hepatitis C virus proteins: E1 - surface protein 1, E2 - surface protein 2. The positions of the synthesized sections of the virus proteins by amino acid sequence are shown in brackets
** - in the numerator - the number of positive samples / in the denominator - the proportion of positive samples in%

Table 5
Determination of antibodies to antigenic determinants of the surface proteins of hepatitis C virus in the blood serum of 5 patients with acute hepatitis C, in whom the infection ended in recovery. Patient ID Hepatitis C virus genotype Testing terms from the onset of the disease (in weeks) Hepatitis C virus RNA Anti-HCV (OD / K * ratio) The level of antibodies to antigenic determinants of surface proteins, expressed as the ratio of OP / to * E1-1 **
(314-328) E2-2
(397-411) E2-3
(483-502) E2-4
(514-531) E2-5
(553-578) 1672 1b 3 + *** 1,5 2.7 1,6 2.0 2.1 2.1 63 - *** 1.4 1.3 1.3 2.0 1.7 1,5 5688 1b 6 + 5.3 2,3 1,6 1,6 2.0 1.9 61 - 1.8 1,2 1,1 1,0 1,6 1.3 10797 3a 5 + 5.5 1.7 1,1 1.4 1,5 1.8 45 - 1.7 - - - - - 2913 3a 3 + 5.2 2,4 1.4 2.1 2.0 2,4 62 - 4.1 - - - + - 8755 3a 7 + 4.9 1,1 1.8 1,2 - - 55 - 1.9 - 1,2 - 1,5 1,5 * - OD / k - the ratio of the optical density of the sample in the enzyme immunoassay to the cutoff level (coefficient k;
** - the name of the peptides corresponding to the proteins of the hepatitis C virus: E1 - surface protein 1, E2 - surface protein 2. The positions of the synthesized sections of the virus proteins by amino acid sequence are shown in parentheses
*** - (+) - positive result, (-) - negative result

Table 6
Determination of antibodies to antigenic determinants, surface proteins of hepatitis C virus in blood serum of 7 patients with acute hepatitis C, in which the infection ended in the formation of a chronic process. Patient ID Hepatitis C virus genotype Testing terms from the onset of the disease (in weeks) Hepatitis C virus RNA Anti-HCV (OD / K * ratio) The level of antibodies to antigenic determinants of surface proteins, expressed as the ratio of OP / to * E1-1 ** (314-328) E2-2 (397-411) E2-3 (483-502) E2-4 (514-531) E2-5 (553-578) 2264 1b 3 + *** 2,5 - - - - - 66 + 4.9 1,5 1.4 1,6 1.7 2.0 3373 1b four + - - - - - - 57 + 5.8 1,5 1.9 2.1 2.0 2.0 4158 1b four + 5.7 1,1 - 1,2 1,2 1,6 56 + 7.3 1.3 2.1 2.1 1.8 2.0 7193 1b 6 + 2,5 - - - - - 62 + 5,6 - - - - - 4718 1b 3 + 5.7 1,2 1,1 1.4 1,1 - 56 + 8.7 1,2 1,0 1,5 1,1 1,5 11529 3a 3 + 4.1 1,1 1,0 1,1 1,2 1.3 45 + 9.3 2.0 1.8 1.9 2,3 2,4 5016 3a 5 + 3.6 - - - - - 56 + 8.1 1,2 1,6 3.0 2.1 2.2 * - OD / k - the ratio of the optical density of the sample in the enzyme immunoassay to the cutoff level (coefficient k);
** - the name of the peptides corresponding to the proteins of the hepatitis C virus: E1 - surface protein 1, E2 - surface protein 2. The positions of the synthesized sections of the virus proteins by amino acid sequence are shown in parentheses
*** - (+) - positive result, (-) - negative result

Claims (1)

A method for predicting outcomes of acute viral hepatitis C by determining antibodies to surface proteins of hepatitis C virus enzyme-linked immunosorbent assay, characterized in that the studies are carried out using 5 synthetic peptides corresponding to antigenic determinants as antigens, surface proteins E1 and E2 of the following formula: NH ₂ - SGHRMAWDMMMNWSP - CONH ₂ NH ₂ - STLTSLPTPGASG - CONH ₂ NH ₂ - RPYAWHYAPRPAGIVPASQV - CONH ₂ NH ₂ - TTDRIFGAPTYSWGENETDVL - CONH ₂ NH ₂ - TWIMNSTGFTKTAGGPPANIGGVGNNT - CONH ₂ and when antibodies are detected in the first 3-7 weeks of the disease, a favorable outcome (recovery) is predicted.