The characteristics of the polyclonal action and immunomodulating activity of bacterial peptidoglycans in oppositely reacting mouse strains]

The data on the specific features of the polyclonal action of gram-negative bacteria on primary immune response to sheep red blood cells in oppositely reacting mouse strains are presented. Staphylococcus aureus and Bacterium flavum peptidoglycans have been found to increase the amount of antibody producing cells to thymus-dependent antigen only in the spleen of low-responsive mice. At the same time differences in the amino acid composition of these heteropolymers do not affect their stimulating activity. Differences between the capacity of B. flavum peptidoglycans to induce the activation of B cells in mice of different strains have been established.     

Genetics of the immune response of karakul sheep vaccinated with colibacillosis and salmonellosis vaccines. II. An analysis of the intensity of the immune response in 1st-generation hybrids

In experiments on hybrid karakul sheep immunized with E. coli and Salmonella vaccines immune response in hybrids F1, obtained from parents oppositely reacting to these vaccines, has been analyzed. The intensity of immune response in karakul sheep has been shown to be inherited as a dominant characteristic, not linked with sex, and regulated, seemingly, by a relatively small number of Ir genes. The content of EA- and EAC-rosetteforming cells does not depend on the intensity of immune response to any of the antigens.     

Genetics of the immune response of Karakul sheep immunized with E. coli and Salmonella vaccines. I. Individual differences in the immune response

The capacity for immune response after immunization with E. coli and Salmonella vaccines has been analyzed in a population of astrakhan sheep, depending on their genotype. Sharply defined individual differences in immune response to the same antigen have been shown, and oppositely reacting animals have been selected. Among the animals showing highly pronounced reaction to one antigen (E. coli) the presence of the animals with a low level of reaction to the other antigen (Salmonella), and vice versa, has been established.     

Immunogenicity of isocomponents of the alpha-toxoid of Cl. oedematiens for mice of opposite reacting genotypes]

There was revealed molecular heterogeneity of the highly purified Cl. oedematiens alpha-toxoid. By the method of isoelectrical focussing alpha-toxoid was divided into isocomponents with the isoelectrical points of 5.33 +/- 0.02 and 4.91 +/- 0.08 with an equal specific activity and serological specificity. In studying the immunogenicity of alpha-toxoid and its isocomponents in experiments on mice of oppositely reacting genotypes it was shown that for mice of the low reacting strain (DBA/2) the the alpha-toxoid isocomponents possessed a much greater immunogenicity than the highly purified alpha-toxoid; under the same conditions the immunogenicity of the alpha-toxoid isocomponents for mice of the highly reacting strain (CBA) failed to differ from the immunogenicity of the highly purified alpha-toxoid.     

Stem cell, T- and B-lymphocyte migration in mouse lines that are high and low reactors to sheep erythrocytes]

Migration of stem cells and B-lymphocytes from the bone marrow and of T-lymphocytes from the thymus was studied on special models in mice of the CBA and C57BL lines, responding to sheep erythrocytes oppositely. Genetically-determined differences in the height of the immune response between the CBA and C57BL mice in immunization with sheep erythrocytes depended to a certain extent on different expression of the process of intensification of migration of the stem cells, T- and B-lymphocytes in response to the antigen administration.     

The adjuvant effect of stearyl tyrosine on a recombinant subunit hepatitis B surface antigen

We describe the enhancement of the antibody response against hepatitis B surface Ag by octadecyl L-tyrosine, a synthetic adjuvant designed to exert its adjuvant effect in a manner similar to that of alum because it binds soluble Ag and releases it slowly from the site of injection. Our data demonstrate that octadecyl L-tyrosine showed a significant enhancement of the antihepatitis B surface Ag response compared to that of alum in the secondary response. The most striking difference between octadecyl L-tyrosine and alum in the antihepatitis B surface Ag antibody response was the absence of IgE-specific antibodies subsequent to immunization of the Ag in octadecyl L-tyrosine. Both the optical isomers of the octadecyl esters of tyrosine were adjuvant active, however, the racemic mixture showed a significantly lowe adjuvant activity. This adjuvant has great potential to be used in humans because it is devoid of side effects as assessed by the lack of acute and chronic toxicity in mice and rats, pyrogenicity in rabbits, formation of granuloma in cats, and adjuvant arthritis in rats.     

The immune response to a synthetic amino acid terpolymer in man: relationship to HL-A type.

The immune response to the synthetic amino acid terpolymer (L-glutamic acid-55 L-lysine-33 L-tyrosine15)n (GLT) was studied in normal human volunteers. Delayed skin test reactivity to this antigen was seen in 34 of 61 subjects immunized with 150 mug of GLT. No antibody to GLT was detected in these responding individuals. There was a close correlation between the in vivo skin reactivity of volunteers to GLT and the ability of their lymphocytes to produce migration inhibitory factor (MIF) in response to GLT in vitro. However, a similar correlation was not seen when the in vitro proliferative response of lymphocytes to GLT, as measured by [methyl-3H] thymidine ([3H] T dR) incorporation, was assayed. HL-A typing of volunteers was studied to determine if responsiveness to GLT was correlated to HL-A type. No statistical association was seen after correction was made for the number of individual HL-A antigens.     

The synthesis, physicochemical properties and immunological activity of 5-amino-3-methylisoxazolo[5,4-d]4-pyrimidinone derivatives

A series of 5-amino-3-methylisoxazole[5,4-d]4-pyrimidinone derivatives were obtained by reacting substituted 5-amino-3-methylisoxazol-4-carboxylic acid hydrazide with ethyl ortho-formate. The compounds were tested using the models of in vivo cellular and humoral immune response in mice and pokeweed mitogen-induced (PWM-induced) polyclonal antibody production in a culture of human peripheral blood mononuclear cells (PBMC). The compounds exhibited differential inhibitory activities in the described models, depending on the character and location of the substituted groups. We suggest that the compounds affect the early stages of the immune response.     

Idiotypic analysis of anti-GAT antibodies. III. Determinant specificity and immunoglobulin class distribution of CGAT idiotype.

The humoral response to poly-(L-glutamic acid60, L-alanine 30, L-tyrosine10), GAT, in mice is further characterized by both idiotype and fine specificity analyses. The common idiotype on murine anti-GAT antibodies (CGAT) was identified in anti-GAT antisera from seven additional strains of mice. These data confirm that the CGAT idiotype can be induced in all inbred strains of mice. Using a partially inbred strain of mice selected for their ability to respond to poly-(L-glutamic acid50, L-tyrosine50), GT, we demonstrated that the GT copolymer is capable of inducing antibodies that express the CGAT idiotype. In contrast, antisera directed against poly-(L-glutamic acid60, L-alanine40), GA, bind GAT but lack CGAT idiotype. These results indicate that GAT molecules contain determinants either similar or identical to those on GT molecules, which are responsible for the induction of CGAT idiotypic antibodies. We also demonstrated that both GAT responder and nonresponder strains of mice can produce anti-GAT antibodies with similar fine specificity patterns and CGAT idiotype. In addition, we demonstrate that antibodies of the IgM, IgG1, and IgG2 immunoglobulin classes express the CGAT idiotype.     

Formation of antibodies against the antigen-recognizing receptors of T-lymphocytes in a syngenous system]

As shown, formation of antibodies to the antigen-recognition receptors of T-lymphocytes was possible in a syngeneic system. The antiserum of CBA mice given intravenous injections of CBA lymphocytes, immune to C57BL cells, proved to specifically inhibit in a mixed culture blasttransformation of CBA T-lymphocytes only against the C57BL cells. The same antiserum failed to influence the proliferative activity of CBA T-lymphocytes reacting to the "foreign" antigen (DBA/2 cells). No antibodies against the C57BL cells were revealed in the antireceptor antiserum. It is assumed that the autoantireceptor antibodies had a regulatory effect on the immune response.     

Soluble proteins induce strong CD8+ T cell and antibody responses through electrostatic association with simple cationic or anionic lipopeptides that target TLR2

The low immunogenicity exhibited by most soluble proteins is generally due to the absence of molecular signatures that are recognized by the immune system as dangerous. In this study, we show that electrostatic binding of synthetic branched cationic or anionic lipopeptides that contain the TLR-2 agonist Pam(2)Cys markedly enhance a protein's immunogenicity. Binding of a charged lipopeptide to oppositely charged protein Ags resulted in the formation of stable complexes and occurs at physiologic pH and salt concentrations. The induction of cell-mediated responses is dependent on the electrostatic binding of lipopeptide to the protein, with no CD8(+) T cells being elicited when protein and lipopeptide possessed the same electrical charge. The CD8(+) T cells elicited after vaccination with lipopeptide-protein Ag complexes produced proinflammatory cytokines, exhibited in vivo lytic activity, and protected mice from challenge with an infectious chimeric influenza virus containing a single OVA epitope as part of the influenza neuraminidase protein. Induction of a CD8(+) T cell response correlated with the ability of lipopeptide to facilitate Ag uptake by DCs followed by trafficking of Ag-bearing cells into draining lymph nodes. Oppositely charged but not similarly charged lipopeptides were more effective in DC uptake and trafficking. Very high protein-specific Ab titers were also achieved by vaccination with complexes composed of oppositely charged lipopeptide and protein, whereas vaccination with similarly charged constituents resulted in significant but lower Ab titers. Regardless of whether similarly or oppositely charged lipopeptides were used in the induction of Ab, vaccination generated dominant IgG1 isotype Abs rather than IgG2a.     

Additional functions for the cysteinyl leukotrienes recognized through studies of inflammatory processes in null strains

Until recently, the cysteinyl leukotrienes, initially termed, slow reacting substance of anaphylaxis, were viewed entirely as effectors of smooth muscle constriction of bronchial airways to impair air flow and of microvasculature to evoke a plasma leak. The development of mice with targeted disruption of the synthesis of the cysteinyl leukotrienes or of their receptor-mediated action has within the last 5 years uncovered new functions in chronic inflammation and in regulation of the adaptive immune response. As innate host responses precede antigen presentation and then follow antigen specific recognition, it is not surprising that we find that the cysteinyl leukotrienes are implicated in both afferent and efferent cell-based immune responses, chronic inflammatory cell responses, and, as originally recognized, in acute smooth muscle constriction.     

Antibodies against nitric oxide damaged poly L-tyrosine and 3-nitrotyrosine levels in systemic lupus erythematosus

Alterations in the amino acid structure or sequence can generate neo-epitopes from self-proteins causing autoaggressive immune attack. Reactive nitrogen species are an important factor that induces post-translational modification of proteins by cellular reduction and oxidation mechanism; cysteinyl-nitrosylation or tyrosine nitration leading to potentially pathogenic pathways. It was thought of interest to investigate the immunogenicity of nitrated poly L-tyrosine vis-á-vis its possible role in the induction of antibodies in systemic lupus erythematosus (SLE). Commercially available poly L-tyrosine was exposed to nitrating species and the damage was monitored by UV spectroscopy and alkaline gel electrophoresis. The results indicated the formation of 3-nitrotyrosine. Nitrated poly L-tyrosine induced higher titre antibodies as compared to the native form. Nitrated poly L-tyrosine was recognized by the autoantibodies present in the sera of patients suffering from SLE by enzyme immunoassays and band shift assay. The possible role of nitrated self-proteins has been discussed in the production of circulating anti-DNA antibodies in SLE.     

DNA vaccination of mice with a plasmid encoding Puumala hantavirus nucleocapsid protein mimics the B-cell response induced by virus infection

Inoculation of naked DNA has been applied for the development of prophylactic and therapeutic vaccines against different viral infections. To study the humoral immune response induced by DNA vaccination we cloned the entire nucleocapsid protein-encoding sequence of the Puumala hantavirus strain Vranica/H?lln?s into the CMV promoter-driven expression unit of the plasmid pcDNA3, generating pcDNA3-VR1. A single dose injection of 50 microg of plasmid DNA into each M. tibialis anterior of BALB/c mice induced a high-titered antibody response against the nucleocapsid protein as documented 6 and 11 weeks after immunisation. PEPSCAN analysis of a serum pool of the pcDNA3-VR1-vaccinated animals revealed antibodies reacting with epitopes covering the whole nucleocapsid protein. The epitope-specificity of the immune response induced by DNA vaccination seems to reflect the antibody response in experimentally virus-infected bank voles (the natural host of the Puumala virus) and humans. The data suggest that DNA vaccination could be used for the identification of highly immunogenic epitopes in viral proteins.     

Chemoenzymatically synthesized multimeric Tn/STn MUC1 glycopeptides elicit cancer-specific anti-MUC1 antibody responses and override tolerance

The MUC1 mucin represents a prime target antigen for cancer immunotherapy because it is abundantly expressed and aberrantly glycosylated in carcinomas. Attempts to generate strong humoral immunity to MUC1 by immunization with peptides have generally failed partly because of tolerance. In this study, we have developed chemoenzymatic synthesis of extended MUC1 TR glycopeptides with cancer-associated O-glycosylation using a panel of recombinant human glycosyltransferases. MUC1 glycopeptides with different densities of Tn and STn glycoforms conjugated to KLH were used as immunogens to evaluate an optimal vaccine design. Glycopeptides with complete O-glycan occupancy (five sites per repeat) elicited the strongest antibody response reacting with MUC1 expressed in breast cancer cell lines in both Balb/c and MUC1.Tg mice. The elicited humoral immune response showed remarkable specificity for cancer cells suggesting that the glycopeptide design holds promise as a cancer vaccine. The elicited immune responses were directed to combined glycopeptide epitopes, and both peptide sequence and carbohydrate structures were important for the antigen. A MAb (5E5) with similar specificity as the elicited immune response was generated and shown to have the same remarkable cancer specificity. This antibody may hold promise in diagnostic and immunopreventive measures.     

Role of L-lysine HCl in adoptive immune therapy towards development of suitable tuberculosis vaccination

L-Lysine HCI is being proposed to be a possible biocompatible adjuvant to enhance immune response by virtue of its probable non-specific bridging action and cellular proliferation properties. This proposal has been tried to be substantiated by designing an in vitro culture protocol, varying the concentration of L-lysine HCI and its further in vivo application. Splenic lymphocyte population has been extracted from mice and co-cultured with extracted mice macrophage population in presence of either Bacille Calmette Guerrin (BCG) or Hepatitis B surface antigen (HbsAg) and added L-lysine hydrochloride in culture media. Post incubation of these cultures, "taught" cell population has been adoptively transferred in na?ve mice. These mice were then challenged by respective antigen dose, Change in Immune response with this challenge was noted. Antibody titre was followed in all the experiments as a measure of immune response. In adoptive immune transfer experiment of with HbsAg (AIT-HbsAg), similar to that with BCG (AIT-BCG), after the incubation period, antibody titre was higher in added lysine containing cultures in comparison with the control ones. Post transfer followed by antigen challenge, in AIT-BCG the expected augmentation in immune response was hardly visible. But in AIT-HbsAg, with the help of lysine booster, the animals responded better as far as the antibody titre is concerned.     

Modulation of the immune response by emotional stress

The influence of mild, emotional stress was investigated for its effect on the immune system by subjecting rats to the one-trial-learning passive avoidance test. The reactivity of the immune system was tested by determining the proliferative response after mitogenic stimulation in vitro as well as the capacity to generate a primary antibody response in vivo after immunization with sheep red blood cells. Our results demonstrate that exposure of rats to a single electric footshock (learning trial) or habituation to the passive avoidance apparatus, induces an increase of the immune response in vitro and in vivo. Thus, emotional stimuli seem to facilitate immunological responsiveness. However, when the animal is confronted with a conflict situation, as tested by the retention of the avoidance response after a single learning trial, the initially enhanced reactivity of the immune system decreases. It is concluded that the immune system is capable of reacting specifically and immediately to distinct psychological stimuli.     

Immunostimulant patch enhances immune responses to influenza virus vaccine in aged mice

Improvement in the immune response to influenza virus vaccination in the elderly represents the primary unmet need in influenza virus vaccination. We have shown that topical application of immunostimulating (IS) patches containing heat-labile enterotoxin of Escherichia coli (LT) enhances immune responses to injected vaccines. We extend these findings and show that LT-IS patch application enhances the antibody responses to influenza virus vaccination in both young and aged mice. LT-IS patches markedly increased influenza virus-specific immunoglobulin G (IgG), hemagglutination inhibition antibody, mucosal antibody, and T-cell responses. The magnitude of the immune responses in aged mice receiving an LT-IS patch was equivalent to or greater than that of the immune responses in young mice given vaccine alone. These results suggest that addition of an LT-IS patch may compensate for the deficient immune function seen in the aged in response to influenza virus vaccination. Therefore, use of an LT-IS patch could be a new, safe, and simple immunization strategy that may significantly improve the outcome of influenza virus vaccination in the elderly.     

Effect on the immobilization-induced stress on the immune response in mice with various behavioral stereotypes

CBA and C57BL/6J mice with aggressive and submissive types of zoo-social behavior fixed during 10-day confrontation testing demonstrated different immune response to immobilization stress. In aggressive mice with confrontation experience stress resulted in a decrease in the immune response in comparison with aggressive inexperienced mice. Therewith, the immune response of CBA mice did not differ from the control level (the immunized mice without experience of victories and defeats), and in C57BL/6 mice the immune response was two times lower than in the control. In contrast to the control and aggressive mice, stress did not suppress the immune response in submissive animals. It is suggested that stress-induced changes in the immune response depend on zoo-social rank of an individual underlain by a particular neurochemical pattern of the brain.     

Significance of initial emotional state for neuroimmunomodulation under conditions of activation or blockade of 5-HT1A receptors

Selective agonist of 5-HT1A receptors--8-OH-DPAT (1 mg/kg) induced a suppression of the immune reaction in aggressive male CBA mice immunized with SRBC (5 x 10(8)). In submissive mice with 10-day defeat experience in confrontation tests, the activation of 5-HT1A receptors with 8-OH-DPAT did not alter the immune response, whereas the application of selective antagonist of 5-HT1A receptors WAY-100635 increased the immune reaction only in submissive mice. It is concluded that activation or blockade of 5-HT1A receptors produced different effects on the immune function of CBA mice depending on the initial emotional state which is known to be provided in aggressive and submissive animals by different activities of the brain neurotransmitter systems including the 5-HTergic system.