[The efficiency of the enzyme immunoassay test system opisthorchiasis-CIC-EIA-best to detect circulating immune complexes containing opisthorchis antigens in the serum of patients with opisthorchiasis].

The efficacy of a kit of Opisthorchiasis-CIC-EIA-Best reagents was evaluated using 270 sera from patients in the study and control groups. The kit showed a sufficient sensitivity (not less than 87.2%) and a high specificity (not less than 97.9%). The use of the above kit of the reagents for enzyme immunoassay in practical healthcare enables one to increase detection rates among the infested subjects on comprehensive examination of those with suspected opisthorchiasis.

[Sensitizing and virus-neutralizing characteristics of goat immunoglobulins to Ebola virus]. / Sensibiliziruiushchie i virusneitralizuiushchie svoistva koz'ikh immunoglobulinov protiv virusa Ebola.

Sensitizing and virus-neutralizing properties of IgG isolated from the sera of goats immunized with Ebola virus and a relevant gammaglobulin prepared by ethanol fractionation were compared. The ratio of the virus-neutralizing activities of subclasses IgG2, IgG1a, and IgG1b was 100:10:1. Anaphylactogenic activity of IgG2 in the immediate type hypersensitivity test in guinea pigs was 2-fold lower than that of IgG1a and IgG1b. Goat gammaglobulin to Ebola virus, consisting from IgG2 antibodies by more than 50%, possessed virus-neutralizing and sensitizing characteristics compatible to IgG2.

[HPLC separation and characterization of tick-borne encephalitis and equine Venezuela encephalomyelitis viral proteins]. / Razdelenie s pomoshch'iu VEZhKh belkov virusov kleshchevogo éntsefalita i venesuél'skogo éntsefalomielita loshadeí i ikh stroenie.

Homogeneous (according to PAGE) capsid and surface viral proteins were isolated from concentrated purified suspensions of tick-borne encephalitis and Venezuelan equine encephalomyelitis viruses by one-stage reversed-phase HPLC. The amino acid composition and the sequences of their N-terminal parts were determined.

[The detection of antibodies to the trophozoite antigens of Lamblia by an immunoenzyme method]. / Vyiavlenie antitel k antigenam trofozoitov liamblii immunofermentnym metodom.

Whether purified antigens of Lamblia intestinalis trophozoites can be used to detect these antibodies by immunoassay. The drugs of immunodominant Lamblia antigens were prepared by anion-exchange chromatography of solubilized trophozoite components and they are mainly presented by proteins having molecular weights of 70, 56, and 49 kD. Immunoassay using these antigens revealed antibodies to Lamblia trophozoite antigens in sera of 87.6% of patients with lambliasis (its diagnosis was established on the basis of microscopic data on the duodenal content) and only in 16.2% of clinically healthy blood donors. Twenty six sera from patients with trichomoniasis having high levels of antibodies to trichomonad antigens were studied to evaluate the specificity of this method for detection of antibodies. It has been found that the proportion of subjects in this group who have also antibodies to Lamblia antigens does not greatly differ from that of healthy blood donors (19.2 and 16.2, respectively).

[Immunoenzyme method of the determination of human chorionic gonadotropin using polyclonal antibodies]. / Immunofermentnyi metod opredeleniia khorionicheskogo gonadotropina cheloveka s ispol'zovaniem poliklonal'nykh antitel.

The authors developed a method for obtaining highly specific polyclonal antibodies reacting with different sites of human chorionic gonadotropin (HCG) and an immunometrical method for measuring HCG in human biological fluids, based on the use of these antibodies. The sensitivity of the method is 10-15 IU/liter HCG, specificity 100%, no cross reactions with LH or FSH were observed. The method was tried in testing urine samples for HCG in women at 1-2 to 34 weeks of gestations and in one cancer patient with the diagnosis of vesical mole.

[The seroepidemiology of toxocariasis in an opisthorchiasis focus in the western Siberian region]. / Seroepidemiologiia toksokaroza v ochage opistorkhoza zapadno-sibirskogo regiona.

Seroprevalence to Toxocara antigens was studied among Novosibirsk inhabitants and a focus of toxocariasis was found in the southern regions of west Siberia. Analyzing the sera of opisthorchiasis patients revealed antibodies to Toxocara antigens, with high titers (1:800 or more) in 1.80% of cases. Immunoblotting of these sera and those from patients with toxocariasis and opisthorchiasis, which were seropositive in one of the above helminths showed that there were mixed human infections with Toxocara and Opisthorchis in this area.

[Development and application of an immunoenzyme test system for diagnosing Ebola fever]. / Razrabotka i primenenie immunofermentnykh test-sistem dlia diagnostiki likhoradki ébola.

Enzyme immunoassay (EIA) test systems for the detection of antigens of and antibodies to Ebola virus were developed and tried. The test system for the detection of Ebola virus antigens based on direct solid-phase EIA detects viral antigens in culture fluid of infected Vero cells, in the blood sera, and in homogenates of infected tissues. Use of this test system allows detection of at least 10 ng of viral proteins or 5.0 x 10(3) to 1.0 x 10(4) PFU/ml in infectious material. The test system is prepared on the basis of protein A - horseradish peroxidase conjugate. It is universal for the testing of animal and human sera and is characterized by high resolution and reproducibility of results. It allows detection of antibodies to Ebola virus starting from days 8-9 of infection. A higher sensitivity of direct solid-phase EIA in comparison with complement fixation or indirect immunofluorescence tests is demonstrated.

[Composition and immunochemical properties of goat immunoglobulins against the Ebola virus]. / Sostav i immunokhimicheskie svoistva kzo'ikh immunoglobulinov protiv virusa ébola.

Serum samples containing Ebola Virus neutralizing antibodies were prepared by prolonged immunization of goats with 10% liver homogenate from guinea pigs infected with Ebola virus. Differences in IgG fractions of normal and hyperimmune caprine blood sera were detected. Analytical chromatography on Polysil SA and immunodiffusion showed the presence of three IgG-containing fractions in hyperimmune sera. Immunochemical properties of these fractions were studied by solid-phase enzyme immunoassay and neutralization test. Antibodies to viral antigens were referred to IgG2 and IgG1a, and virus neutralizing properties were found mainly in IgG2 antibodies. Immunoglobulins were isolated from hyperimmune serum by alcohol sedimentation. The principal IgG fraction was found to contain much lower levels of antibodies to guinea pig liver antigens than intact serum, but at the same time it was characterized by a higher neutralization index.

[Study of antigenic structure of HIV-1 protein p24 using monoclonal antibodies]. / Izuchenie antigennoi struktury belka p24 VICh-1 s pomoshch'iu monoklonal'nykh antitel.

During the experiments 4 murine and 3 rat hybridomas producing monoclonal antibodies (MAb) against the protein p24 of human immunodeficiency virus type 1 (HIV-1) have been obtained. Using the immunoblotting technique, it was established that all the species of MAb reacted with the same viral proteins which are derivatives of gag gene--p24 and p55. The properties of MAb have been studied in competitive binding. Their ability of binding to different fragments of the gag protein produced by the recombinant plasmids in E. coli cells have been investigated in ELISA. The analysis of the findings suggests that the HIV-1 protein p24 contains at least 3 antigenic epitopes. All species of MAb reacted with 3 different HIV-1 strains and 2 HIV-1 isolates, but failed with 2 different HIV-2 strains. The only MAb NS5E4 can be used as an immunosorbent in the antigenic capture reaction.

[High performance liquid chromatography and characterization of structural proteins of the influenza virus]. / Vysokoéffektivnaia zhidkostnaia khromatografiia i kharakterizatsiia strukturnykh belkov virusa grippa.

Constituent proteins of human influenza virus A have been separated by reverse-phase HPLC on Polysil ODS-500. Their homogeneity is confirmed by the data of amino acid composition, Edman analysis and gel electrophoresis.

[Immunochemical and biological properties of synthetic peptide fragments from the 124-144 sequence of human leukocyte interferon alpha2]. / Immunokhimicheskie i biologicheskie svoistva sinteticheskikh peptidnykh fragmentov posledovatel'nosti 124-144 leikotsitarnogo interferona cheloveka alpha2.

Three peptides corresponding to the sequences 124-144, 124-138, 129-144 of the human leukocyte interferon alpha 2 (IFN-alpha 2) were synthesized. The synthesis was performed by DCC-HOBT coupling of protected peptide segments in solution. The segments were obtained by the active ester coupling methodology using base-labile 2-[4-(phenylazobenzyl)sulfonyl]ethyl (Pse) group as carboxyterminal protection. After complete deprotection with 1 M methanesulphonic acid in trifluoroacetic acid--thioanisol--m-cresol mixture the peptides were purified by reversed-phase chromatography. The studies of interaction of the peptides with rabbit antiserum against IFN-alpha 2 revealed at least one minor antigenic determinant within the 124-144 region of IFN-alpha 2 amino acid sequence. Rabbit antisera developed against peptides 124-138 and 129-144 showed ability of binding recombinant IFN-alpha 2 and neutralizing its antiviral activity. Free peptides or their conjugates with bovine serum albumine did not display antiviral activity, neither could they inhibit the activity of IFN-alpha 2.

[The use of filamentous phage M13 in protein engineering]. / Ispol'zovanie nitchatogo faga M13 dlia belkovoi inzhenerii.

M13B1 vector based on the filamentous phage M13 has been constructed. M13B1 phage carries the gene of resistance to ampicillin and contains the unique site of recognition for BamHI restriction endonuclease in gene VIII coding for the major coat protein. BamHI restriction site has been inserted into the gene of the major coat protein by means of oligonucleotide directed mutagenesis. The synthetic DNA fragment coding for the model peptides has been inserted through BamHI site into the M13B1 DNA. The possibility of inserting foreign peptides into the N-terminus at maintaining the viability of hybrid phages has been shown. The differences in specificity of the recombinant phage maturation have been determined by analysing the amino acid sequence of B-protein.

[Antigenic properties of synthetic fragments of the heavy chain of influenza virus A hemagglutinin]. / Antigennye svoistva sinteticheskikh fragmentov tiazheloi tsepi gemaggliutinina virusa grippa A.

The antigenic properties of the synthetic peptides corresponding to the regions 122-133, 136-147, 154-164 of the virus A/Aichi/2/68 hemagglutinin heavy chain have been studied. The 122-133 and 136-147 peptides comprise together almost whole antigenic determinant A, while the 154-164 peptide is a part of determinant B. Rabbits immunized by the peptides conjugated with carrier-protein BSA gave the high immune response to hapten-peptides. Each antiserum reacted only with homologous conjugate. All the antipeptide serums reacted with the virus A/Aichi/2/68 fixed on the base. Conjugate of the 136-147 peptide reacted with the rabbit antiserum against the virus A/Aichi/2/68 rendering the direct evidence to location of at least one hemagglutinin antigenic determinant in the region 136-147.

[2-(4-Chlorophenyl)sulfonylethoxycarbonyl (Cps) amino-protecting group for the synthesis of peptides in a solution. Synthesis of [Leu]enkephalin and its [D-ala2]analog]. / 2-(4-Khlorfenil)sul'fonilétoksikarbonil'naia (Cps) aminozashchitnaia gruppa dlia sinteza peptidov v rastvore. Sintez [Leu]énkefalina i ego [D-Ala2]analoga.

Solution syntheses of [Leu]enkephalin and its [D-Ala2]analogue were accomplished using a new 2-(4-chlorophenyl)sulfonylethoxycarbonyl (Cps) base-labile group for amino protection and a chromogenic acid-labile 4-(4-phenylazo)benzyloxybenzyl (Abz) group for carboxyl protection. The syntheses were performed by stepwise attachment of Cps-amino acids, which were introduced as pentachlorophenyl esters or as dicyclohexylammonium salts in the presence of tris(dimethylamino)chlorophosphonium perchlorate. To remove Cps-group, Abz-esters of Cps-peptides were treated with two molar equivalents of 1,8-diazabicyclo[5.4.0]undec-7-ene in dimethylformamide followed by neutralization of the base with an excess of 1-hydroxybenzotriazole; the deblocked amino components were then used without isolation. Fully deblocked pentapeptides were purified and characterized by HPLC, FAB mass spectra and amino acid composition.

[Synthesis of peptide fragments of influenza virus A/Aichi/2/68 (H3N2) hemagglutinins]. / Sintez peptidnykh fragmentov gemaggliutinina virusa grippa A/Aichi/2/68 (H3N2).

Peptides corresponding to sequences 122-133, 136-147, and 154-164 of the heavy chain of hemagglutinin of the A/Aichi/2/68 (H3N2) influenza virus have been synthesized by stepwise elongation of the peptide chain with Boc-amino acid activated esters or by condensation of peptide blocks by DCC/HOBt-method. A coloured C-protecting group, 2-[4-(phenylazo)-benzylsulfonyl]ethyl (PSE), was used, which is convenient in purification of synthetic peptides. After removal of terminal N-and C-protecting groups the side-protecting residues were cleaved off with 1 M trifluoromethanesulfonic acid in trifluoroacetic acid containing 10% thioanisole. Crude products were purified by preparative reversed-phase liquid chromatography. Synthesized peptides were conjugated with BSA.