Immunostimulating activity of polycomponent vaccine "Immunovac-VP-4" and grippol after their combined administration

The experimental study of the immunostimulating activity of therapeutic bacterial polycomponent vaccine VP-4 and prophylactic vaccine grippol, introduced both separately and in combination, on mice infected with Salmonella typhimurium, used as a model. Both preparations were found to produce an immunomodulating effect. The combined subcutaneous injection of VP-4 and grippol did not decrease their immunostimulating activity, but their separate administration at an interval of 14 days resulted in essential decrease in the protective activity of each of these two preparations. As shown on the model of Klebsiella infection in mice, challenged 4 weeks after immunization, VP-4 ensured the survival of 78.6% of mice, while after the injection of grippol their survival rate was not different from that of the group of intact animals. The evaluation of the immunostimulating activity of these preparations under the conditions of the prophylaxis of influenza and acute respiratory infections in organized groups of children revealed that the use of VP-4 alone or grippol in combination with VP-4 considerably decreased the number of secondary bacterial complications in children.     

Changes in the immunotropic activity of neutrophilokins in the course of experimental staphylococcal infection

The influence of the products secreted by activated neutrophils (neutrophilokins) of mice, both intact and infected with staphylococci, on the activity of mouse spleen cells in the graft-versus-host reaction, immune response to sheep red blood cells and the antigen-presenting function of peritoneal macrophages was studied. Neutrophilokins of intact mice stimulated the activity of immunocompetent cells. Neutrophilokins obtained from infected mice on day 3 after infection produced an immunosuppressing effect. On day 7 after infection the immunostimulating activity of neutrophils was restored and showed practically no difference from the normal level.     

Signaling pathways initiated by beta-hydroxy-beta-methylbutyrate to attenuate the depression of protein synthesis in skeletal muscle in response to cachectic stimuli

To investigate the mechanism by which beta-hydroxy-beta-methylbutyrate (HMB) attenuates the depression of protein synthesis in the skeletal muscle of cachectic mice, a study has been carried out in murine myotubes in the presence of proteolysis-inducing factor (PIF). PIF inhibited protein synthesis by 50% within 4 h, and this was effectively attenuated by HMB (25-50 muM). HMB (50 muM) alone stimulated protein synthesis, and this was attenuated by rapamycin (27 nM), an inhibitor of mammalian target of rapamycin (mTOR). Further evidence for an involvement of this pathway was shown by an increased phosphorylation of mTOR, the 70-kDa ribosomal S6 kinase (p70(S6k)), and initiation factor 4E-binding protein (4E-BP1) and an increased association of eukaryotic initiation factor 2 (eIF4E) with eIF4G. PIF alone induced a transient (1-2 h) stimulation of phosphorylation of mTOR and p70(S6k). However, in the presence of HMB, phosphorylation of mTOR, p70(S6k), and 4E-BP1 was increased, and inactive 4E-BP1-eIF4E complex was reduced, whereas the active eIF4G.eIF4E complex was increased, suggesting continual stimulation of protein synthesis. HMB alone reduced phosphorylation of elongation factor 2, but this effect was not seen in the presence of PIF. PIF induced autophosphorylation of the double-strand RNA-dependent protein kinase (PKR), leading to phosphorylation of eIF2 on the alpha-subunit, which would inhibit protein synthesis. However, in the presence of HMB, phosphorylation of PKR and eIF2alpha was attenuated, and this was also observed in skeletal muscle of cachectic mice administered HMB (0.25 g/kg). These results suggest that HMB attenuates the depression of protein synthesis by PIF in myotubes through multiple mechanisms.     

Immunomodulating properties of non-steroidal anti-inflammatory drugs]

There has been studied the influence of a number of nonsteroidal antiinflammatory agents (NSAID ) on the humoral immune response of mice in immunization with erythrocytic and viral antigen. It has been found out that NSAID have immunomodulating effect, stimulating humoral immune response (4-iodantipyrine, 4-bromantipyrine) or suppressing it (butadione, sodium salicylate). Apparently the mechanism of NSAID ++ immunostimulating effect is related to the inhibition of T-suppressors ++ function by the latter ones.     

Culture conditions affecting induction and release of lymphocyte produced proliferation inhibitory factor (PIF)

Studies on the factors affecting the production of a proliferation inhibitory factor (PIF) by human lymphocytes are presented. Maximal PIF production occurred with mitogen stimulation of blood lymphocytes cultured at 1 × 10⁶/ml. Optimal cultures contained 10% fetal calf serum, but PIF could be produced in the absence of serum, and after only a 6-hr pulse exposure to PHA. PIF production was found to correlate with lymphocyte activation in response to the mitogen PHA but was not related to lymphocyte proliferation (DNA synthesis). Inhibitory activity could be detected as early as 3 hr after mitogen addition, long before DNA synthesis occurs. The mitogens Con A and PWM initiated different intensities of DNA synthesis in these cultures, but similar quantities of PIF. Antigenic stimulation of sensitive human peripheral lymphocyte populations resulted in the release of PIF. Cells from donors that gave a strong positive skin test to tuberculin (PPD) responded in tissue culture to PPD by producing PIF, while the cells from skin test negative donors did not. A small quantity of PIF was also evident in the supernatants from cultures with no known stimulus (“unstimulated”), this was found to result from activation of the lymphocytes by nonlymphoid elements and by fetal calf serum. An investigation of the PIF-producing capabilities of other lymphoid tissues showed that lymph node cells produced this humoral factor, whereas thymus cells did not. Thymus cell supernatants, in fact, were found to contain an extremely labile cytotoxin which degraded rapidly upon storage.     

The effect of Bilirubin on the phagocytic activity of mouse peripheral granulocytes and monocytesin vivo

Using an in vitro phagocytic assay with synthetic 2-hydroxyethylmethacrylate copolymer particles, the phagocytic activity of leukocytes of bilirubin-treated mice (85 and 170 mumol/L in 0.5 mL intraperitoneally) was studied. Bilirubin treatment significantly stimulated the phagocytosis of both peripheral blood granulocytes and monocytes; the increase of phagocytosis persisted for 6 h after bilirubin injection. The potential immunostimulating and/or immunotoxic effect of bilirubin is discussed.     

Effect of synthetic polyribonucleotides on the immunological and colony-forming activity of irradiated bone marrow cells

The experimental data are presented concerning the effect of polyribonucleotides on the immunologic and colony forming ability of bone marrow or irradiated mice. All the compounds under study exhibited a pronounced, but to a different degree, colony-forming and immunostimulating action. The comparative study of the influence of polyribonucleotides on the number of endogenous colonies and antibody-forming cells showed an inverse relationship between these parameters: The preparations exerting the most pronounced immunostimulating effect had an insignificant colony-forming action and vice versa. This is evidently indicative of the capacity of these preparations to turn the differentiation of haemopoietic stem cells towards the immunopoiesis.     

Metabolic changes in the peritoneal macrophages of mice differing in the H-2 locus of histocompatibility after intraperitoneal administration of salmozan

The activity of 5'-nucleotidase in mouse peritoneal macrophages differing by histocompatibility locus H-2 after intraperitoneal injection of salmozan, an immunostimulating agent, has been studied. The character of changes in the activity of 5'-nucleotidase in peritoneal exudate macrophages after the intraperitoneal injection of salmozan has proved to be unrelated to the genotype of mice. The injection of salmozan induces a deep and prolonged decrease in the activity of 5'-nucleotidase in these macrophages. In mice of different strains changes in the activity of 5'-nucleotidase after the intraperitoneal injection of salmozan are of a linear type and can be approximated by a linear regression model.     

Bioactive peptides derived from food proteins preventing lifestyle-related diseases

Many kinds of bioactive peptides which might prevent lifestyle-related diseases are released from food proteins after enzymatic digestion. Inhibitory peptides for angiotensin I-converting enzyme (ACE) having anti-hypertensive effect have been isolated from enzymatic digests of various food proteins. LKPNM, which was isolated from the thermolysin digest of dried bonito was activated 8-fold by ACE itself and showed a prolonged effect after oral administration. Two vasorelaxing peptides, ovokinin and ovokinin(2-7), showing antihypertensive effect after oral administration were obtained from ovalbumin digests. We found that low molecular weight peptides derived from food proteins lowered serum cholesterol without increasing excretion of cholesterol and bile acids. An immunostimulating peptide isolated from an enzymatic digest of soybean protein prevented alopecia induced by cancer chemotherapy.     

Polymorphonuclear leukocyte-inhibitory factor of Bordetella pertussis. III. Inhibition of Arthus reaction and peritoneal infiltration of PMN

In vivo biologic effects of the polymorphonuclear leukocyte-inhibitory factor (PIF) of Bordetella pertussis were tested by using two experimentally induced inflammatory processes in mice. The intravenous injection of a partially purified extract from phase I bacteria strongly inhibited the glycogen-induced peritoneal infiltration of polymorphonuclear leukocytes (PMN) and the Arthus reactions, whereas little inhibitory activity was found in the extract from phase III bacteria. The activity was localized in the outer membrane of phase I bacteria, as was the in vitro PIF activity, and the two activities gave the same behavior in DEAE-cellulose chromatography. Therefore the observed suppression of inflammatory processes in mice is probably due to the inhibitory action of PIF on the function of PMN in vivo.     

Effect of pertussis vaccine on the functional activity of the peritoneal and splenic macrophages in 2 mouse strains genetically differing by the intensity of their immune response

The immunostimulating effect of corpuscular pertussis vaccine on the antigen-presenting and bactericidal functions of peritoneal and splenic macrophages in CBA and C57BL/6 mice, differing in the intensity of immune response to sheep red blood cells and Salmonella typhimurium, has been studied. The study has revealed that the injection of pertussis vaccine alters the functional activity of the cells under study, the effect depending on the immunizing dose, the strain of mice and the time elapsed from the moment of immunization. Pertussis vaccine enhances the low capacity of macrophages for antigen presentation in C57BL/6 mice with low responsiveness and alters the resistance of peritoneal and splenic macrophages to the cytopathic action of salmonellae.     

STP (the substance produced by a strain of Streptococcus sp. Thom-1606) as a stimulant of the nonspecific resistance of the macroorganism

Preparation STP, a new immunostimulating agent, is a substance produced by Streptococcus strain sp. Thom-1606 and capable of enhancing the nonspecific activity of the body as shown in animal experiments. The optimal dose-time parameters of the administration of the immunostimulator have been established by the method of the mathematical planning of experiments. As a result, the survival of all animals used in the experiment has been achieved. Mouse peritoneal macrophages have been found to form the population of target cells whose phagocytic activity is enhanced under the effect of the immunostimulating agent STP.     

Cleavage of human interleukin 1: isolation of a peptide fragment from plasma of febrile humans and activated monocytes

Interleukin 1 (IL 1) is a product(s) of mononuclear phagocytes, and has multiple biologic activities that mediate several host responses to infection and inflammation. Highly purified IL 1 activates lymphocytes, induces fever, increases hepatic acute phase protein synthesis, and increases muscle protein degradation. A 4.2 kd peptide has been purified from plasma of febrile humans which also induces muscle proteolysis in vitro (termed proteolysis-inducing factor, PIF). Because IL 1 purified from activated human monocytes induces muscle proteolysis in vitro, studies were performed to determine the relationship of human monocyte-derived IL 1 to plasma-derived PIF. Purified PIF was highly active in the IL 1 thymocyte assay. After gel filtration of plasma from febrile patients, fractions with PIF activity also induced thymocyte proliferation and fever in mice. Thus, it seems likely that the plasma peptide PIF has IL 1 properties and probably represents a small m.w. cleavage product of IL 1. Further studies confirmed this finding. Highly purified 15 kd IL 1, rechromatographed over different gel filtration media, consistently fragmented into a 4 kd peptide with both muscle proteolysis-inducing and lymphocyte-activating properties. The breakdown of the 15 kd IL 1 into biologically active smaller fragments increased with time, and could be accelerated by trypsinization. The monocyte-derived IL 1 fragments were partially destroyed by heat. Highly purified 125I-labeled 15 kd IL 1 also fragmented into subunits, and these radioactive subunits produced fever in mice and were active in the thymocyte assay. Fragmentation of 125I-labeled 15 kd IL 1 was reduced by agents that inhibit proteases. These results indicate that some of the biologic activities of human IL 1 are conserved in small m.w. fragments. These studies also provide evidence that IL 1 may circulate in humans as a 4.2 kd peptide, and that this cleavage product can function as an active mediator of IL 1 effects in the host.     

Effect of trypsin on suppressor cell formation and function in localized staphylococcal infection

The present study has been made on (CBA X C57BL)F1 mice immunized with sheep red blood cells (SRBC) and inoculated with staphylococci (M-SRBC-S). The injection of splenic lymphocytes from syngeneic M-SRBC-S into intact mice has been found to suppress immune response to SRBC in these mice. The injection of trypsin into M-SRBC-S decreases the suppressive action of their lymphocytes on SRBC-induced immune response in syngeneic recipients. The injection of trypsin into the recipients has been found to produce no effect on the immunosuppressive action of transplanted lymphocytes obtained from M-SRBC-S. The injection of trypsin into M-SRBC-S induces the release of the factor, inhibiting the formation and function of suppressor cells, by their splenocytes. Previously formed suppressor cells block the release of the immunostimulating factor by the splenocytes of the animals receiving the injections of trypsin.     

Characterization of novel components of the baculovirus per os infectivity factor complex

Baculovirus occlusion-derived virus (ODV) infects insect midgut cells under alkaline conditions, a process mediated by highly conserved per os infectivity factors (PIFs), P74 (PIF0), PIF1, PIF2, PIF3, PIF4, and PIF5 (ODV-E56). Previously, a multimolecular complex composed of PIF1, PIF2, PIF3, and P74 was identified which was proposed to play an essential role during ODV entry. Recently, more proteins have been identified that play important roles in ODV oral infectivity, including PIF4, PIF5, and SF58, which might work in concert with previously known PIFs to facilitate ODV infection. In order to understand the ODV entry mechanism, the identification of all components of the PIF complex is crucial. Hence, the aim of this study was to identify additional components of the PIF complex. Coimmunoprecipitation (CoIP) combined with proteomic analysis was used to identify the components of the Autographa californica multiple nucleopolyhedrovirus (AcMNPV) PIF complex. PIF4 and P95 (AC83) were identified as components of the PIF complex while PIF5 was not, and this was confirmed with blue native PAGE and a second CoIP. Deletion of the pif4 gene impaired complex formation, but deletion of pif5 did not. Differentially denaturing SDS-PAGE further revealed that PIF4 forms a stable complex with PIF1, PIF2, and PIF3. P95 and P74 are more loosely associated with this complex. Three other proteins, AC5, AC68, and AC108 (homologue of SF58), were also found by the proteomic analysis to be associated with the PIF complex. Finally the functional significance of the PIF protein interactions is discussed.     

CD40/CD40 ligand interactions are critical for elicitation of autoimmune-mediated fibrosis in the lung

Pulmonary interstitial fibrosis (PIF), associated with persistent inflammation and increased collagen deposition in the interstitium, is often considered an autoimmune disease. Hapten immune PIF (HIPIF), a model for PIF, is elicited in the lung by a single intratracheal (i.t.) challenge in mice sensitized with hapten (2,4,6-trinitrobenzene sulfonic acid, TNBS). In this study, we characterized the role of CD40/CD40 ligand (CD40L) interactions in the elicitation of secondary cell-mediated immune responses that lead to development of fibrosis in the lung using an adoptive transfer model of HIPIF. The expression of CD40 was detected on bronchoalveolar lavage (BAL) cells 1-3 days after i.t. challenge with hapten in the HIPIF lung, but not lungs from the control mice. The CD40(bright) BAL cells morphologically resembled infiltrating monocytes. Furthermore, blocking CD40/CD40L interactions with blocking Ab decreased BAL production of Th1-mediators (IL-12 and TNF-alpha). Moreover, either blocking CD40/CD40L interactions with the Ab or using IL-12 knockout recipient mice prevented the increased collagen deposition (accumulation of hydroxyproline) in the lungs during HIPIF induction. We conclude that second signals (CD40/CD40L interactions) are required for elicitation of secondary immune responses that lead to PIF in vivo. The results support the notion that CD40/CD40L interactions are involved in the pathogenesis of an ongoing autoimmune disease.     

Experimental study of the immunostimulating properties of tomitsid

Tomicide, a preparation with antibacterial properties, accumulates in the culture medium during the growth of one of streptococcal strains. The injection of the preparation into mice simultaneously with the antigen (sheep red blood cells) produces an adjuvant effect. Tomicide has been found capable of inducing the production of interferon detected in the serum of the animals. During experimental stress created by intensive exercise tomicide prevented a decrease in the normal (anamnestic) level of antibodies, produced an immunostimulating effect and, at the same time, enhanced the total physical endurance of the animals, manifested by an increased duration of swimming.