The improvement of immunobiological preparations against leptospirosis. An experimental study of a new concentrated purified vaccine against icterohemorrhagic leptospirosis for human immunization

The findings of the study of immunological structure of the population in regions endemic for leptospirosis indicate that the immune status of humans makes it impossible to obtain titrated blood sera for the preparation of antileptospirosis immunoglobulin. The data obtained in the study of the immunobiological properties of a new concentrated vaccine against icterohemorrhagic leptospirosis show the possibility of using this vaccine for the immunization of donors with the aim of obtaining blood sera to be used as raw material for the production of immunobiological preparations.     

Cytotoxic action of the chemical substances found as admixtures in medical immunobiological preparations

The cytotoxic action (CTA) of chemical substances contained as admixtures in medical immunobiological preparations on human diploid cells has been studied. Such chemical substances as rivanol and merthiolate in admissible concentrations show the highest degree of CTA. The results obtained in this investigation indicate that different concentrations of chemical substances may produce equal CTA; thus, thiolate in toxic in a dose of 0.8 microgram/ml; the same CTA is produced by aluminium sulfate in a concentration of 500 micrograms/ml. Small doses of chemical substances, producing no explicit manifestations of the cytotoxic effect, may have latent CTA determined by additional methods of investigation. CTA may be manifested as lethal, sublethal and latent cell lesions. In working out regulations on the test for CTA it is expedient to indicate admissible residual amounts of chemical substances contained in finished medical immunobiological preparations, considering that these amounts must be incapable of producing CTA in cell cultures. The conclusion has been made on the expediency of denoting small amounts of chemical substances capable of producing latent CTA as tentatively tolerable doses.     

The chromosome-damaging action of 2 chemical vaccine contaminants on mice

The cytogenetic effects of two chemical agents, hydroxylamine used for the destruction of bacterial cells and thimerosal added to many immunobiological preparations as preservative, were studied in vivo by their action on the marrow cells of C57BL/6J mice. The preparations under study, when injected intraperitoneally in a wide range of doses, including subtoxic ones, induced no chromosomal aberrations. At the same time cyclophosphamide, an antitumor cytostatic agent used for positive control, produced a pronounced damaging effect on chromosomes.     

Effect of preparations of protein Yop encoded by Yersinia pestis calcium-dependence plasmid on mice

The impact of the preparations of Y. pestis secreted proteins Yop (YopH-M, YopB, YopD-N, YopE) on mice immunized with 3 s.c. injections was studied. Though these proteins failed to protect the animals from plague, they stimulated the immunobiological transformation in the immunized animals. YopB and YopD-N were found to have the highest immunobiological activity with respect to mice. The preparation of YopB induced the production of the highest titers of specific antibodies and stimulated cell-mediated immune response. The injection of YopD-N to mice led to a considerable decrease in the proliferative capacity of splenocytes in vitro in response to stimulation with nonspecific mitogen ConA, as well as to pathological changes in the kidneys.     

Substantiation of the composition, technology and standardization of the original medicinal forms of interferon and bactisporin

New medicinal forms of immunobiological preparations--human lekocytic interferon and bactisporin--have been developed for local application in dentistry, surgery, gynecology. As the basis for these preparations, the pharmacopeial collagen solution has been used. The results obtained in this investigation indicate that the preparations are safe and possess wound-healing properties.     

Physicochemical and immunobiological properties of the dialysate antigen of Bordetella pertussis

The study of the physicochemical and immunobiological properties of B. pertussis dialysate antigen indicates that the antigen has a complex composition and possesses hemagglutinating and lymphocytosis-promoting activity, which permits further studies with a view to developing diagnostic and prophylactic preparations on the basis of this antigen.     

Study of the immunobiological properties of a soluble antigen of Rickettsia prowazekii in an experiment

The results obtained in the study of the immunobiological properties of R. prowazekii soluble antigen purified without the use of ether are presented. The effectiveness of this antigen has been shown to be not inferior to that of preparations obtained by ether purification. It is expedient to introduce the antigen in the adsorbed form in two injections at an interval of 10--14 days, as immunization in two injections produces phase changes in the immune responsiveness of animals.     

Use of a diploid cell line for detecting the toxic components in medical immunobiological preparations

Besides specific antigens medical immunobiological agents (MIBA) contain chemical compounds (formaldehyde, aluminium hydroxide and mercury salt, merthiolate) in permissible concentrations. Therefore, the investigation of MIBA and their components should involve methods studying the effect of chemical compounds on cells and their structural components. For this purpose WHO recommends to use cell cultures. The results obtained show that cell cultures (constant and diploid lines) allow the differentiation in the degree of toxicity of chemical compounds constituting MIBA. Merthiolate had the strongest irreversible lethal effect. The technique can prove useful for more accurate evaluation of toxicity in inactivated bacterial and viral vaccines as well as in serum preparations. Cell culture can be successfully used for the detection of toxic components in vaccines and serum drugs, with the final safety tested by their injection to animals.     

Effect of carbohydrates and polyols on amide content and protein fragmentation in a lactoglobulin preparation

Certain carbohydrates and polyols are used at various stages of the production of immunobiological preparations as stabilizers of biological activity, particularly in the production of lactoglobulin (against opportunistic pathogens) using membrane ultrafiltration. This study concerns the effect of these substances on changes in the amide content in proteins of this lactoglobulin. Lactoglobulin was incubated in near-physiological (0.9% NaCl, pH 5.5) 10% solutions of glucose, fructose, and sorbitol at 4 and 35 degrees C for 7, 14, and 28 days. A lactoglobulin solution in 0.9% NaCl, pH 5.5, was used as the control. All substances studied suppressed the reduction of the amide group content of asparagine and, in contrast, increased the rate of amide group removal from glutamine residues in proteins of lactoglobulin preparations.     

Current problems of immunoprophylaxis of infectious diseases and standardization of medical immunobiological preparations

The state of immunoprophylaxis in the whole of the USSR and in individual Union Republics in 1981-1982 is ralyzed. The connection between an increase in diphtheria, pertussis and measles morbidity and the widening of the scope of contraindications to vaccination has been revealed. The optimum vaccination tactics in Union Republics with regard to differences in their climatic conditions and demographic situation is planned. The problems of the standardization of prophylactic and therapeutic immunobiological preparations are considered. Organizational measures leading to the improvement of their quality are outlined.     

Development of a Soviet diagnostic kit for determining class M immunoglobulins to the hepatitis A virus by immunoenzyme analysis (a test system for anti-HAV IgM)

A new test system Diagn-A-Hep for the laboratory diagnosis of hepatitis A (HA) by means of the enzyme immunoassay has been developed at the Institute of Poliomyelitis and Viral Encephalitides (Moscow). The sensitivity and specificity of the newly developed test system have proved to be similar to those of the well-known commercial diagnostic system HAVAB manufactured by Abbott Laboratories (USA). Diagn-A-Hep permits the diagnosis of HA with 96-100% effectiveness both in patients with the acute form of the disease and in patients with its anicteric or inapparent forms. This system is simple and convenient, it may be employed in inadequately equipped laboratories or even under field conditions. The rules for the selection of immunobiological preparations to be included in the test system have been worked out.     

Lack of interference of common phytoecdysteroids with production of nitric oxide by immune-activated mammalian macrophages

Effects of selected common phytoecdysteroids on immunobiological responses triggered by lipopolysaccharide and interferon-gamma (IFN-gamma) were tested under in vitro conditions using murine resident peritoneal macrophages. Namely, production of nitric oxide was investigated. The series of test agents encompassed ecdysteroids occurring often as major components of the ecdysteroid fraction in numerous plant extracts: 20-hydroxyecdysone (20E), polypodine B, ajugasterone C, ponasterone A and inokosterone. Their structural variability concerns only variation in the number and position of hydroxyls. Two additional side-chain modified ecdysteroids: makisterone A (with a methyl substituent at position 24) and carthamosterone (with a cyclic side-chain lactone), and three ecdysteroid analogs: poststerone, rubrosterone and dihydrorubrosterone (devoid of side chains) were included into the test series. All test compounds, except of ponasterone A, represent natural substances isolated from the medicinal plant Leuzea carthamoides and are supposed to be significant for the often reported pharmacological activities of preparations derived from this species. However, the tested ecdysteroids did not interfere with the immunobiological activity of the immunocompetent cells. Our results thus differ from the so far reported information.     

Immunological properties of the preparations of the anti-anthrax antigen]

The results of examination of immunological properties of the preparations of anthrax protective antigen on laboratory animals (guinea pigs) confirmed the efficacy of using the lactic-peptone medium for obtaining the anthrax protective antigen. Incubation for 18 hours at 37 degrees C of the strain-producer (STI-1) and a double immunization scheme with the antigen obtained proved to be the most rational conditions for inducing the immunological response in the vaccinated laboratory animals. Three fractions of the anthrax protective antigen obtained possessed weaker immunobiological properties than the whole preparation of this antigen.     

The protective effect of preparations made from plant seedlings in experimental Pseudomonas aeruginosa infection

The influence of preparations obtained from oat and wheat seedlings (immunostimulating factors IF-1 and IF-2, respectively) on the natural resistance of mice to P. aeruginosa infection was studied. IF-1 and IF-2 were introduced intraperitoneally in a single injection in doses of 100 micrograms and 1000 micrograms per mouse 2 and 7 days prior to the inoculation of P. aeruginosa strain 8 in doses of 1 and 10 LD50. The presence of substances capable of stimulating the immunobiological reserves of the body in actively growing plants (seedlings) was shown.     

Liposomes as carriers of polyfunctional immunogens

Liposomes are promising carriers for construction of the up-to-date chemical vaccinal preparations. The immunogenic and immunomodulating properties of liposomes may be varied by incorporation of the natural or synthetic immunomodulators into the inner water volume or into the lipid bilayer parallel with antigens as well as by introduction of the receptor-specific vector to definite types of immunocompetent cells into liposomes. The pronounced immunobiological properties of the liposomal carrier are shown in studies of liposomes conjugated with haptens or model protein antigens. The application of liposomes as carriers of bacterial antigens induces a delayed catabolism of the antigen and formation of its depot. The immunomodulating properties of antigen-containing liposomes rise after introduction of such immunomodulators as lipid A, muramyldipeptide or interleukin-1 into the liposome composition.     

Recombinant diphtheria toxin derivatives: Perspectives of application

Diphtheria toxin (DT) is a unique bacterial protein which consists of three domains with various biological functions. Using genetic engineering for the creation of various recombinant constructions of DT with definite features, it is possible to create unique tools for cellular biology and toxins with efficient and selective action on certain populations of cells. The review highlights the structural and functional aspects of the DT molecule, its fragments and domains, as well as the major areas of application of its recombinant derivatives. In particular, the perspectives for practical use of recombinant DT derivatives are discussed for creating immunobiological preparations, cytotoxins, blockers of the heparin-binding epidermal growth factor-like growth factor (HB-EGF), protein constructions for direct delivery of substances into the cell, and also the possibility to use DT recombinant derivatives for therapy and prevention of a number of diseases.     

Current state of problem of improving tools for plague vaccine prophylaxis

Literature data on main immunobiological characteristics of 1st generation plague vaccines as well as ways of development of new tools for specific prophylaxis of plague: recombinant live, chemical, antiidiotypic, and DNA vaccines are presented in the review. Their expected advantages and disadvantages, perspectives of development and practical use in system of antiepidemic measures are assessed.     

Effect of carbohydrates and polyols on amide content and protein fragmentation in a lactoglobulin preparation

Certain carbohydrates and polyols are used at various stages of the production of immunobiological preparations as stabilizers of biological activity, particularly in the production of lactoglobulin (against opportunistic pathogens) using membrane ultrafiltration. This study concerns the effect of these substances on changes in the amide content in proteins of this lactoglobulin. Lactoglobulin was incubated in near-physiological (0.9% NaCl, pH 5.5) 10% solutions of glucose, fructose, and sorbitol at 4 and 35°C for 7, 14, and 28 days. A lactoglobulin solution in 0.9% NaCl, pH 5.5, was used as the control. All substances studied suppressed the reduction of the amide group content of asparagine and, in contrast, increased the rate of amide group removal from glutamine residues in proteins of lactoglobulin preparations.Translated from Prikladnaya Biokhimiya i Mikrobiologiya, Vol. 41, No. 1, 2005, pp. 29–34.Original Russian Text Copyright © 2005 by Bibov, Vachaev, Sorokina, Lukash, Sinichkin, Yagovkin.     

Development and testing of an enzyme immunoassay-based monoclonal test system for the detection of the Yersinia pestis V antigen

An enzyme immunoassay-based test system for Y. pestis V antigen detection was developed. The specificity and sensitivity of this system met the requirements for medical immunobiological preparations for the identification of causative agents of highly fatal diseases. The sensitivity of the test system was assessed, and its high specificity was also demonstrated: the test system did not detect bacterial cells of closely related (four Y. pseudotuberculosis strains) and heterologous microorganism strains. The test system developed was able to detect the V antigen at concentrations as low as 2.0 ng/mL in cells of nine experimental Y. pestis cultures. The obtained preparation can be recommended for use in laboratory diagnostics of plaque.