[A standard panel of human immunodeficiency virus-positive and -negative blood sera for assessing the sensitivity and specificity of diagnostic immunoenzyme test systems]. / Standartnaia panel' pozitivnykh i negativnykh k virusu immunodefitsita cheloveka syvorotok krovi dlia otsenki chuvstvitel'nosti i spetsifichnosti diagnosticheskikh immunofermentnykh test-sistem.

The materials on the development of a reference panel of HIV-positive and negative blood sera required for quality control of diagnostic enzyme-immunoassay systems are summarized. Ninety sera (50 HIV-antibody positive and 40 negative) were examined in 2 test systems of national and 3 test systems of foreign companies as well as by immune blotting and immunofluorescence tests. Each serum was characterized by optic density values and antibody titer (for positive sera). The conditions of storage and transportation of serum panels as well as those for control tests were determined. The license and instructions for use for the serum panel have been approved. The serum panel is used in 9 institutions engaged in working out and manufacture of diagnostic test systems.

[Immunobiological aspects of AIDS]. / Immunobiologicheskie aspekty problemy SPIDa.

The growing pandemia of AIDS, which resulted in about 40,000 AIDS patients and about 3 million infected persons by the end of 1986, demands for the urgent creation of methods for diagnosis, prevention and treatment of the disease. The present paper analyzes the main aspects of AIDS immunobiology, i. e. the molecular genetics of the virus, production of the viral components, construction of kits for immunoenzyme detection of antibodies to the virus, development of confirmatory immunoenzyme assays. The authors discuss the prospects of creating the synthetic antigens of the AIDS virus or producing them on the basis of genetic engineering both for the diagnosis and prophylaxis of the infection.

[Rapid immunoenzyme diagnosis of influenza in patients with various allergoses and bronchial asthma]. / Immunofermentnaia ékspress-diagnostika grippa u bol'nykh razlichnymi allergozami i bronkhial'noi astmoi.

In an investigation carried out in the allergological clinic of the Tbilisi State Medical Institute in the period between two outbreaks of influenza, the presence of influenza antigen was determined in nasal washings taken from 127 patients with different allergoses and bronchial asthma by means of the enzyme immuno-assay with the use of the type-specific virion antigen of M1-protein. This method was found to be highly sensitive and to have some advantages over traditional methods used for the diagnosis of influenza. In patients with preasthma and different forms of bronchial asthma elevated susceptibility to influenza infection and its unfavorable influence on the clinical course of these pathological conditions were established.

[Islet cell surface autoantibodies: their immunoenzyme analysis using rat target cells]. / Autoantitela k poverkhnosti ostrovkovykh kletok podzheludochnoi zhelezy: immunofermentnoe opredelenie s ispol'zovaniem kletok-mishenei krys.

A hard phase immunoenzymatic system for primary screening and subsequent quantitative determination of autoimmunobodies to the surface of islet cells (ASIC) was worked out using rat target cells. ASIC organ-specificity was confirmed by the absence of crossreactions with rat hepatocytes and splenocytes. The determination of the upper normal bound with 99% confidence interval combined with a high sensitivity of the method allowed an objective and significant assertainment of ASIC-positive sera even with a low level of antibodies. ASIC quantitative characteristic is their titer determined with the help of the intersection of a titration curve with the upper normal bound. ASIC were detected approximately in half of the patients with insulin-dependent diabetes of a duration of maximum 5 years and were not detected in the patients with insulin-dependent diabetes compensated with diet and sugar lowering drugs using the above method.

[Stimulation of the immune response to immobilized antigen in an in vitro system with B-activin]. / Stimuliatsiia immunnogo otveta na immobilizovannyi antigen v sisteme in vitro B-aktivinom.

The influence of B-activin, the preparation of immunomodulating myelopeptides, on the level of antibody formation after the primary immunization of mouse splenocyte cultures with immobilized antigens has been studied. The treatment of the cells with B-activin on the third day of their cultivation in the presence of peroxidase immobilized on polystyrene or protein M1 of influenza virus has been found to increase antigen-specific antibody formation by several times, while having practically no effect on the total level of IgG secretion. The stable level of the stimulation of antibody formation and the possibility of its quantitative evaluation in the enzyme-linked immunosorbent assay makes this immune response inducing system a convenient model for testing the biological activity of myelopeptides and other immunostimulators.

[Immunoenzyme determination of antibodies to the surface of islands of Langerhans in autoimmune destruction of the insular apparatus]. / Immunofermentnoe opredelenie antitel k poverkhnosti ostrovkovykh kletok podzheludochnoi zhelezy pri autoimmunnoi destruktsii insuliarnogo apparata.

Enzyme-linked immunosorbent assay (ELISA) was applied for detection of human islet cell surface antibodies (ICSA) to rat islet target cells. In 23 healthy controls without hereditary diabetes the findings were on the upper normal limit (mean value of optical density + 3 SEM). The results above the limit were considered positive. 11 out of 18 insulin-dependent (Type I) diabetics with the disease duration less than 5 years were ICSA-positive. All 9 patients with insulin-independent (Type 2) diabetes were ICSA-negative. 3 out of 18 healthy subjects (siblings and children of probands with type II diabetes) were strongly ICSA-positive, although all the members of this risk group had unimpaired oral glucose tolerance test. Thus, ELISA screening of ICSA may be useful for discriminating patients with different types of diabetes and revealing nonaffected individuals at high risk according to their beta-cell integrity.

[Analysis of the antigenic and immunogenic properties of protein M of the influenza virus by an immunoenzyme method]. / Analiz antigennykh i immunogennykh svoistv belka M u virusa grippa immunofermentnym metodom.

A test system permitting the detection of influenza virus protein M at a concentration of 0.1-0.5 ng/ml in ELISA has been developed. The use of this system made it possible to detect influenza viruses A and B directly in crude virus-containing material and clinical samples obtained from influenza patients. During the outbreak of influenza in the spring of 1983 ELISA was successfully used for the rapid diagnosis of influenza, and some of its advantages in comparison with the conventional immunofluorescence test were thus demonstrated. To overcome difficulties arising from the low immunogenic potency of protein M, in the process of obtaining diagnostic sera and ascitic fluids the animals were immunized with the conjugate of protein M and polyelectrolite, which ensured considerable activation of humoral immune response.

[Antigenic properties of the M1 proteins of influenza type B viruses and the detection of a common antigenic determinant of the M1 proteins of type A and B viruses]. / Antigennye svoistva belkov M1 virusov grippa tipa B i vyiavlenie obshchei antigennoi determinanty belkov M1 virusov tipa A i B.

Antigenic properties of M1 proteins of influenza B viruses were studied by indirect EIA using monospecific antisera to M1 protein obtained by immunization of rabbits and mice. Antisera with highest titres were obtained by immunization of mice with polyelectrolyte-conjugated M1 protein. Antigenic heterogeneity of M1 proteins of influenza B viruses was demonstrated. M1 proteins of B/Lee/40 and B/USSR/03/84 viruses reacted with B/Hong Kong/72 antiserum to one-fourth of the homologous titre. Cross-experiments using M1 proteins recovered from influenza type A and B viruses and antisera to them revealed heterologous reactions suggesting a common antigenic determinant in A and B M1 proteins. Treatment of the antisera with M1 protein of type A resulted in a decline of antibody titres to M1 proteins of type B. The two available monoclones to M1 protein of type A reacted only with M1 A but not with M1 B.

[Rapid diagnosis of influenza by detecting viral M protein in an immunoenzyme test]. / Ekspress-diagnostika grippa s pomoshch'iu vyiavleniia virusnogo belka M v immnofermentnom teste.

Previously developed ELISA test system with sensitivity about 0.5 ng/ml of virus protein M was used for influenza virus detection in nasopharyngeal washings of patients with acute respiratory virus diseases (ARVD). Altogether 184 specimens from patients with ARVD and 31 from patients with other infections were examined in the pre-epidemic and epidemic periods of 1983. In parallel, virus antigens were detected by direct immunofluorescence test (IF). The total frequency of viral antigen detection by ELISA and IF coincided (63% of the specimens examined). With the specimens collected early in the disease (2-3 days) the rate of virus findings by ELISA rose to 82%. Direct detection of viral antigen in nasopharyngeal washings by means of an objective immunochemical method seems to be promising for a large-scale rapid diagnosis of influenza.

[Production of hyperimmune sera and immune ascitic fluids to influenza virus protein M by immunization with a protein-polyelectrolyte conjugate]. / Poluchenie giperimmunnykh syvorotok i immunnykh astsiticheskikh zhidkostei k belku M virusa grippa pri immunizatsii kon''iugatom belka s poliélektrolitom.

A conjugate of influenza A virus M protein with an immunostimulating polyelectrolyte was demonstrated to stimulate markedly antibody production in mice. Production in this method of immunization of immune ascitic fluids makes it possible to use this method for generation of highly active immune diagnostic preparations.

[Antigenic characteristics of influenza virus protein M. The ELISA detection of the differences in the M proteins of remantadine-sensitive and -resistant variants of the virus]. / Antigennye kharakteristiki belka M virusa grippa. Vyiavlenie metodom ELISA razlichii belkov M chuvstvitel'nogo i ustoichivogo k remantadinu variantov virusa.

Antigenic characteristics of influenza A virus M protein were studied by ELISA using a monospecific antiserum to M protein and monoclonal antibodies to the B4 and A7 antigenic determinants of M protein. The design of the test systems for M protein detection was based on the indirect and "sandwich" variants of ELISA as well as on the previously developed principle of blocking the indirect reaction. The latter variant of the test system had the highest specificity: 0.1--0.5 ng of specific protein. The high specificity of the method allows subtle antigenic differences of M protein within influenza A virus group to be detected. Comparative studies of remantadine-sensitive and resistant variants of the classic fowl plague virus showed the previously demonstrated significant differences in the physico-chemical properties of M protein of these variants to correlate with a marked antigenic divergence associated, in particular, with greater antigenicity of B4 epitope in M protein of remantadine-sensitive strains. The test system of ELISA blocking was found to be useful for M protein detection in virus-containing materials not subjected to purification and concentration (native allantoic fluids). The latter attests to the expedience of using ELISA in clinical diagnostic studies of influenza.

[ELISA immunoenzyme detection of the antigens of interferon and protein contaminants]. / Vyiavlenie antigenov interferona i belkovykh primesei v ego preparatakh s pomoshch'iu immunofermentnogo testa ELISA.

The possibility of specific detection of interferon antigens by ELISA was demonstrated on a model of partially purified and ultrafiltration-concentrated preparations of mouse fibroblast interferon. ELISA allows differentiation of specific interferon antigens and the main protein contaminants of its preparations: bovine serum albumin and virus-inducer proteins.

[Study of human diploid cell strains for the presence of oncornavirus determinants]. / Issledovanie shtammov diploidnykh kletok cheloveka na prisutstvie determinant onkornavirusov.

The WI-38 strain of human diploid cells (HDC) and two strains, L-58 and L-63 isolated in Moscow Research Institute of Virus Preparations were examined in the course of sequential passages for the presence of primate oncornaviruses and their antigens. In parallel, the tumorigenic capacity of the cells was tested by inoculating them into the cheek pouch tissue of Syrian hamsters. In all cases the examined HDC cultures contained no oncornavirus particles or their antigens and in no case showed any infectious activity determined in the KC-test. Only on one subculture of the L-63 strain cells at the 44th passage was a positive result obtained in immunoprecipitation test with antiserum to the LPV oncornavirus. Cells of the L-58 strain which had undergone 27 and 43 passages showed tumorigenicity in hamster experiments. In subsequent passages of these HDC strains no such properties were found. The regular control for the absence of oncogenic message is a necessary condition for the use of HDC strains in virological practice.

[Immunological characteristics of LPV oncornavirus produced by T-9 human cell line]. / Immunologicheskie kharakteristiki onkornavirusa LPV, produtsiruemogo liniei chelovecheskikh kletok T-9

The results of immunological study of oncornavirus (LPV strain) produced by a continuous human T-9 cell line are presented. The method of immunodiffusion in agar revealed the following constituent antigens in the virus: (a) those identical to internal and external antigens of Mason-Pfizer oncornaviruses particles; (b) those specific only for LPV virus and not common in other known oncornaviruses of mammals. These antigens were common in LPV virus from T-9 culture and from xenogeneic T-BHK culture in which Mason-Pfizer virus antigens were absent completely; and (c) interspecific antigen of oncornavirus C type present in minimal amounts. Localization of the above antigens in virus particles of LPV oncornavirus was confirmed by the electron immunoenzyme method. Upon separation of virus polypeptides in polyacrylamide gel it was found that the antigens cross-reacting with Mason-Pfizer virus as well as LPV specific antigens were localized both in the main inner virus protein and in the surface glycoprotein.