Stability of the immunogenic properties of plague vaccine strain EV, Research Institute of Epidemiology and Hygiene line, during long-term storage]

The experiments in guinea pigs showed that the immunogenic properties of plague vaccine strain EV, line NIIEG, freeze-dried in 1947 and stored under vacuum without animalization, remained unchanged for 30 years. The subcultures prepared from this train showed, after three passages in guinea pigs, good immunogenic properties which preserved for 6--10 years (the term of observation). After 30-years storage the stock culture of strain EV, line NIIEG, can be used for the preparation of NIIS live plague vaccine.     

Immunogenicity of Yersinia pestis grown on nutrient media at 28 and 37 degrees C

The immunogenicity of Y. pestis strain EV, grown in yeast-casein medium, yeast medium with Hottinger digest and yeast medium with sunflower-seed protein at 28 degrees C and 37 degrees C, for guinea pigs and white mice has been studied. As revealed in this study, these media ensure the formation of highly immunogenic populations of Y. pestis strain EV and, therefore, can be used for growing Y. pestis vaccine strains. Considerable fluctuations in the content of such highly protective antigen as fraction 1 do not affect the immunogenicity of live cultures of Y. pestis strain EV. This is due to the leveling of differences in the content of this antigen in the process of the multiplication of these bacteria in laboratory animals.     

Lectin of Yersinia pestis vaccine strain EV and its immunological properties

As the result of the chromatographic separation of Y. pestis EV membrane proteins, a protein fraction with hemagglutinating activity was obtained. The isolated preparation was glycoprotein with a molecular weight of 22 kD, contained 16% of carbohydrates and exhibited thermolabile properties. The determination of the carbohydrate specificity of this glycoprotein revealed that it belonged to the class of lectins. Changes in the content of 11 corticosteroids and the population composition of lymphocytes, as well as the detection of specific antibodies in the blood serum of guinea pigs immunized with lectin, were indicative of the fact that the preparation was sufficiently immunogenic and induced the activation of the processes of proliferation and activation of lymphocytes during immunogenesis. The lectin isolated from Y. pestis EV outer membrane may be regarded as an additional factor ensuring the contact of the pathogen with the cells of the body and as a promising component of combined plague vaccine.     

The effect of the immunization of animals with a live plague vaccine on the lysosome count in organ-specific macrophages

Vital fluorochromatic lysosomes of peritoneal, liver, splenic and lung macrophages of white mice, white rates, and guinea-pigs are studied. Reliable differences in a quantity of lysosomal granules of macrophages from various tissues as well as differences between macrophages from the same tissues of different experimental animals are found. At 21 days after animal immunization with live plague vaccine EV the most significant changes in the number of lysosomal granules are revealed in white mice. The number of lysosomes in guinea pigs increased in 1 and 7 days after vaccination, in 14 days their number became normal.     

Changes in the functional activity of neutrophils during their interaction with Yersinia pestis in vitro

The functional state and electrochemical properties of human blood neutrophil leukocytes after their in vitro interaction with Y. pestis cells, strain EV, was analyzed. A considerable decrease in the electrophoretic mobility of neutrophil leukocytes and a considerable increase in their phagocytic indices was shown. At the same time the maximum phagocytic activity in the total pool of isolated neutrophil leukocytes was registered in fractions having higher electrophoretic mobility. The dependence of electrophoretic mobility on the state of neutrophil membranes, as well as the degree of their activation, is discussed.     

The morphological characteristics of globulin production during the vaccinal process induced by tularemia and brucellosis vaccines

Significant data on the dynamics of globulin production in guinea pigs in the process of immunogenesis after the injection of Francisella tularensis vaccine strain or conjugated brucellosis vaccine have been obtained by means of immunofluorescence and the enzyme immunoassay. The number of globulin-producing cells in lymphoid organs (the spleen, regional and remote lymph nodes) differs, depending on the injected antigen. The relationship between the character of immunomorphological changes in lymphoid organs and the dynamics of the increase of antibody titers in the peripheral blood of the animals after their immunization with conjugated brucellosis vaccine and the injection of avirulent F. tularensis has been established.     

Lymphokines which influence electrophoretic mobility of macrophages.

Supernatants of blood lymphocytes from immunized guinea pigs after incubation with purified protein derivative (PPD) were fractionated on Sephadex G-75. The fractions were tested for activity to change the electrophoretic mobility of macrophages. Dependent on incubation time, three different regions of activity with an average molecular weight of 13 000, 40 000 and more than 100 000 were estimated.     

Synergistic effects of active specific immunotherapy and chemotherapy in guinea pigs with disseminated cancer

Sewall Wright strain 2 guinea pigs bearing pulmonary metastases of the syngeneic line 10 (L10) hepatocarcinoma were treated with a vaccine composed of 10(7) bacillus Calmette-Guérin admixed with 10(7) x-irradiated L10 tumor cells beginning 10 days after tumor inoculation. Although this treatment failed to cure most of the guinea pigs of their metastatic disease, histologic examination of the pulmonary tumors in the vaccinated guinea pigs provided evidence of a cell-mediated hypersensitivity response that disrupted the normally compact architecture seen in control tumors. When a monoclonal antibody against the L10 tumor was injected i.v. to evaluate the vascular permeability of the tumors, significantly more antibody localized in tumors of vaccinated guinea pigs than in tumors of untreated controls. These results suggested that blood-borne substances could be delivered more efficiently to L10 metastases after the tumor-bearing guinea pigs had been treated with vaccine. To determine whether such increased vascular permeability would enhance the antitumor effects of chemotherapeutic agents, combined immunotherapy and chemotherapy studies were performed. Although cyclophosphamide treatment by itself did not cure L10-bearing guinea pigs, cyclophosphamide used in conjunction with prior immunotherapy increased the survival rate of animals to more than twice that of animals treated with immunotherapy alone (74 vs 33%). These results suggest that one mechanism by which active specific immunotherapy enhances chemotherapy of disseminated tumors is by rendering tumor foci more permeable to subsequently administered cytotoxic drugs.     

The heterogeneity of the alveolar macrophages of guinea pigs immunized subcutaneously with a vaccinal strain of Yersinia pestis]

The study of alveolar macrophages obtained from guinea pigs at different periods after the subcutaneous immunization with Y. pestis vaccine strain has revealed the heterogeneity of these macrophages in their bactericidal activity with respect to Y. pestis and in their resistance to the cytopathic action of this microorganism, as well as in the content of lysosomes and in the expression of receptors on the cell surface. The study has shown that subcutaneous immunization does not lead to the redistribution of subpopulations and to changes in their digestive activity.     

Effect of histamine on the rosette-forming capacity of T-lymphocytes in immunization with ADPT vaccine and its components

The results obtained in the study of the influence of histamine on the capacity of T-lymphocytes of guinea pigs immunized with DPT-vaccine and its components for spontaneous rosette formation are presented. Histamine at a concentration of 10(-3) M has been found to inhibit the capacity of blood and splenic lymphocytes of guinea pigs immunized with adsorbed DPT vaccine for spontaneous rosette formation. The inhibitory effect is more pronounced after the immunization of the animals with adsorbed DPT vaccine and Bordetella pertussis suspension.     

Immunobiological characteristics of impurities in corpuscular influenza vaccines

Admixtures of free antigens have been shown to play the main role in the anaphylactogenic danger of vaccines. The immunogenic and anaphylactogenic action of such antigenic admixtures in corpuscular influenza vaccine can be observed after the immunization of animals in 2 or 3 injections. Host antigens incorporated into viral particles induce no anaphylactic reaction in guinea pigs after their immunization in 3 injections.     

Ribosomal dysentery vaccine. II. Biological trials of active protection for guinea pigs and mice]

Ribosomal vaccine from Sh. sonnei injected subcutaneously once or twice in physiological saline or in Freund's complete adjuvant produces a marked protective effect against experimental keratoconjunctivitis in guinea pigs. Inhibition of the protective effect by high doses (above 100 microgram) of ribosomal vaccine is evident after a single, but not repeated injections. Protective effect in mice is achieved by immunization with very low doses of ribosomal vaccine: ED50 is 1.2 ng after challenge with 5.6 LD50. The nature of immunogenic factor responsible for the biological activity of the ribosome vaccine is still obscure. In contrast to Boivin's antigen, ribosomal preparations, even in high doses (1000--2000 microgram), have no toxic effect on mice and guinea pigs.     

Immunization of guinea pigs with Neisseria gonorrhoeae: strain specificity and mechanisms of immunity.

Infection of subcutaneusly implanted chambers in guinea pigs conferred immunity against homologous infection of other chambers in the same animals. However, attempts to immunize guinea pigs by subcutaneous injection of filtered fluid from infected chambers, or with small doses of formalin-killed, chamber gonococci were not successful. Thus, neither organisms grown in vivo nor their extracellular products appeared to be exceptionally immunogenic. In immunizing tests with different isolates of gonococci adapted to growth in guinea-pig chambers, cross-immunity to chamber infection with low challenge doses was detected only between two of six isolates. The killing of gonococci in chambers of immunized animals, which occurred only after homologous challenge or with the heterologous strain showing cross-immunity, was not due primarily to humoral factors in the chamber fluid but probably to an enhanced effectiveness of phagocytosis. The serum of immunized animals was bactericidal for homologous strains and for the strain showing cross-immunity but not for strains showing no cross-immunity. Hence, serum bactericidal activity might be a useful indicator for investigating the specificity of immunity produced by different gonococcal strains.     

Immunogenic activity of temperature sensitive mutation of herpes simplex virus type-1 in mono- and polyvalent conditions with different attenuated strains of virus. I. Analysis of humoral immunity induced by mutant temperature sensitive herpes simplex virus type-1 in monovalent systems

The aim of the present study was the analysis of the immunogenic activity of temperature sensitive mutant of HSV-1 with significantly decreased pathogenicity for mice. The stability of immunogenic potency was also tested. The level of antibody-mediated response in guinea pigs after two doses of mutant ts HSV-1 or native strain was compared. Antibodies to HSV were measured using ELISA and CFM. Seroconversion rates in tested groups were high, from 80% to 100%. The level of antibody response at 4 week after inoculation measured by ELISA and CFM showed no significant differences between 4 passages of mutant ts HSV-1. Significant higher increase of antibodies level after two doses of viruses was observed for mutant ts HSV-1 as compared to native strain, both in ELISA and CFM.     

Evaluation of vaccinal immunogenesis by the peroxidase method

The possibility of evaluating functional immunomorphogenesis in the course of the vaccinal process after the injection of conjugated and live brucellosis vaccines, as well as conjugated plague antigen and Yersinia pestis strain EV, to guinea pigs has been shown by means of the direct and two-layer variants of the immunoperoxidase assay. The dynamics of the accumulation of globulin-producing cells in the immunocompetent organs and the time course of immunoglobulin titers in the peripheral blood after the injection of live and conjugated vaccines have been followed up. These data may be used for the morphological evaluation of approved preparations.     

Differences in immunogenicity and protection in mice and guinea pigs following intranasal immunization with Helicobacter pylori outer membrane antigens

Mice and guinea pigs were intranasally immunized with either recombinant lipoprotein 20 or Helicobacter pylori outer membrane vesicles (OMV). Cholera toxin was used as mucosal adjuvant. In mice, both vaccines elicited systemic and local IgG responses, which correlated with significantly lower levels of H. pylori colonization. In contrast, only OMV proved immunogenic in guinea pigs, with the development of both systemic and local immune responses. These antibodies did not, however, correlate with protection in these animals, which suggests that vaccine formulation is as important as choice of antigen in the development of an H. pylori vaccine.     

Macrophage-T cell interaction mediated by immunogenic and non-immunogenic forms of a monofunctional antigen

Summary As an approach to the elucidation of the essential steps in the immune pathway, the uptake and retention of immunogenic and non-immunogenic analogs of a monofunctional antigen by guinea pig macrophages and the efficiency of macrophages pulsed with the compounds to present antigen to sensitized T lymphocytes were compared. L-Tyrosine-azobenzene-p-arsonate (RAT) and its non-immunogenic analog, 4-hydroxyphenyl-n-propane-3-azobenzene-p-arsonate (RAN), react similarly with antiarsonate antibody, but RAN, unlike RAT, is unable to induce cellular immunity in guinea pigs. The uptake and retention patterns of the two compounds by macrophages differed in that, at a given time, more RAN than RAT was retained and detectable on cell surfaces by anti-arsonate antibody. Equivalent numbers of T lymphocytes from guinea pigs sensitized to RAT formed antigen-dependent clusters with macrophages pulsed with either RAT or RAN after 24 hr in culture, but not with macrophages pulsed with an azobenzenoid compound of unrelated specificity. On the other hand, T lymphocytes from guinea pigs immunized with RAN showed no significant capacity to bind to macrophages which had been pulsed with any of the compounds. The number of lymphocytes from RAT-sensitized animals which bound to RAT-pulsed macrophages remained relatively stable over a 48 hr period, whereas clusters of the same lymphocytes with RAN-pulsed macrophages dissocitated to background levels within that time. Early cluster formation mediated by RAN, as well as its ability to induce transient specific T cell unresponsiveness to RAT in vivo, indicate that T cells are capable of recognizing (binding) the non-immunogen. However, such early, and perhaps weak, interaction with RAN-pulsed macrophages did not induce DNA synthesis by T cells. Anti-Ia serum completely blocked cluster formation mediated by either RAT or RAN. Thus, the only significant distinction disclosed by these studies between the immunogenic and non-immunogenic compounds was the stability of macrophage-T cell interaction as determined by the persistence of antigen mediated cell clusters in culture, suggesting that this may be a factor in immunogenic discrimination.Abbreviations ABA azobenzenearsonate - BSA bovine serum albumin - CFA complete Freund's adjuvant - IFA incomplete Freund's adjuvant - KLH keyhole limpet hemocyanin - LNC Lymph node cells - MHC major histocompatibility complex - PEC peritoneal exudate cells - PEL peritoneal exudate lymphocytes - RAN 4-hydroxyphenyl-n-propane-3-azobenzene-p-arsonate - RAT L-tyrosine-azobenzene-p-arsonate - TAT L-tyrosine-azobenzene-p-trimethylammonium chloride Aided by USPHS Grant AI 05664.     

Major histocompatibility complex restriction of T-cell responses to varicella-zoster virus in guinea pigs.

Varicella-zoster virus (VZV), adapted to grow in guinea pig fibroblasts, was injected subcutaneously into Hartley, strain 2, and strain 13 guinea pigs. Serum immunoglobulin G antibodies were detected 2 weeks later, and T-cell proliferative responses by blood lymphocytes were found 3 weeks after injection. The proliferating cells bound the 155 antibody, which defines a CD4-like subset of guinea pig T lymphocytes. VZV-infected fibroblasts of human, Hartley, and strain 13 origin elicited equivalent amounts of proliferation, which was quantitatively greater than that obtained with an extracted VZV antigen. Uninfected (control) human or guinea pig fibroblasts did not elicit T-cell proliferation. The proliferative response to VZV required the presence of autologous (strain 2 or 13) antigen-presenting cells and was blocked by the addition of an anti-class II major histocompatibility complex antibody. Effector cells obtained from in vitro cultures mediated class II-restricted cytotoxicity to L2C cells incubated with VZV. Class I-restricted responses were obtained only by cross-priming strain 2 animals with strain 13 peritoneal exudate cells which had been preincubated with VZV. The data indicate that guinea pigs resemble humans in that class II-restricted T cells with specificity for VZV are more readily cultured from blood than are class I-restricted cells.     

乙型脑炎减毒活疫苗(SA_(14)-14-2)在豚鼠体内保护作用的免疫机制的研究

本实验将乙脑减毒活疫苗ＳＡ_（１４）－１４－２株以不同疫苗病毒量（３．８７ＰＦＵ／ｍｌ和５．８７ＰＦＵ／ｍｌ）分别一次免疫豚鼠,观察其对强毒攻击后抑制毒血症和抗体形成的能力。结果显示疫苗（５．８７ＰＦＵ／ｍｌ）免疫组豚鼠攻击前虽然中和抗体阴性或很低,但经攻击感染后不同时间内均未出现病毒血症,对照组豚鼠则于第２,３,４天全部出现病毒血症。表明一次活疫苗免疫后能有效地抑制病毒血症的产生。免疫后３０天虽然免疫组的豚鼠中和抗体很低,但攻击感染后抗体迅速增长。第四天的抗体滴度为１：８～３２,第５天达１：１２８～２５６,第１４天抗体高达１：５１２～１０２４;而对照组抗体则上升很慢,第７天才出现低水平抗体（１：４）。血凝抑制抗体增长的动态与中和抗体近似。表明活疫苗免疫后虽然中和抗体水平不高,但一经感染可迅速产生高滴度抗体达到保护作用。     

Immunogenicity of Plague Vaccines in Mice and Guinea Pigs

The median effective doses (ED₅₀) of 28 lots of killed Pasteurella pestis strain 195/P vaccine were determined in mice and guinea pigs. Mice were injected with vaccine alone, whereas guinea pigs received vaccine suspended in incomplete Freund's adjuvant. Potency ratios of vaccines were obtained by comparing the ED₅₀ of the test with that of a reference vaccine. Mean potency ratios of 1.82 ± 0.50 in mice and 3.22 ± 0.56 in guinea pigs were obtained, and the difference between these means was significant, P = <0.01. The number of organisms in the challenge dose did not significantly affect the ED₅₀ of a vaccine in guinea pigs. However, irrespective of vaccinating route, nearly 1,000 times as much vaccine was required in the absence of adjuvant as in its presence to produce comparable protective indexes in the guinea pig. The response of guinea pigs did not offer any improvement over mice in evaluating the efficacy of plague vaccines.