Effect of the lymphocytosis-stimulating factor from Bordetella pertussis on murine lymphoid and hemopoietic cells

Effect of B. pertussis lymphocytosis-promoting factor (LPF) on the lympho-hematopoietic system of mice was studied. The injection of LPF was shown to sharply enhance endogenous colony formation and to induce a severe depletion of thymus cells, reaching its maximum of day 4. Thymocytes obtained on day 2 or 3 after the injection of LPF produced a suppressive effect on endogenous colony formation. The proliferative activity of hematopoietic stem cells sharply increased under the influence of LPF, though it had no radioprotective action. On the following day after the injection of LPF a steep rise in the number of hematopoietic stem cells was observed in the blood of mice: their content increased 20-fold in comparison with the control level. These data may be important for the evaluation of the side effects of pertussis vaccine on the lympho-hematopoietic system.     

Changes in dynamics of phase transitions in various liquids by recording of acoustic mechanical impedance of a drying drop

A method of studying multicomponent liquids is proposed, which is based on recording the dynamics of the acoustomechanical impedance of a drop that dries up on the surface of a quartz resonator oscillating with an ultrasound frequency. The magnitude of the acoustomechanical impedance is an integral characteristic of the physical properties of the drop such as viscosity, composition, surface tension, moistening, and inner structure. Using liquids of different types as an example, it was shown that each liquid possesses its individual "portrait", which is determined by the phase transitions. The method can be used for the screening identification of liquids (determining the degree of consistency with the standards) in solving a number of scientific and practical problems, as well as in medicine.     

Helminth Infection and Commensal Microbiota Drive Early IL-10 Production in the Skin by CD4+ T Cells That Are Functionally Suppressive

The skin provides an important first line of defence and immunological barrier to invasive pathogens, but immune responses must also be regulated to maintain barrier function and ensure tolerance of skin surface commensal organisms. In schistosomiasis-endemic regions, populations can experience repeated percutaneous exposure to schistosome larvae, however little is known about how repeated exposure to pathogens affects immune regulation in the skin. Here, using a murine model of repeated infection with Schistosoma mansoni larvae, we show that the skin infection site becomes rich in regulatory IL-10, whilst in its absence, inflammation, neutrophil recruitment, and local lymphocyte proliferation is increased. Whilst CD4⁺ T cells are the primary cellular source of regulatory IL-10, they expressed none of the markers conventionally associated with T regulatory (T_reg) cells (i.e. FoxP3, Helios, Nrp1, CD223, or CD49b). Nevertheless, these IL-10⁺ CD4⁺ T cells in the skin from repeatedly infected mice are functionally suppressive as they reduced proliferation of responsive CD4⁺ T cells from the skin draining lymph node. Moreover, the skin of infected Rag^-/- mice had impaired IL-10 production and increased neutrophil recruitment. Finally, we show that the mechanism behind IL-10 production by CD4⁺ T cells in the skin is due to a combination of an initial (day 1) response specific to skin commensal bacteria, and then over the following days schistosome-specific CD4⁺ T cell responses, which together contribute towards limiting inflammation and tissue damage following schistosome infection. We propose CD4⁺ T cells in the skin that do not express markers of conventional T regulatory cell populations have a significant role in immune regulation after repeated pathogen exposure and speculate that these cells may also help to maintain skin barrier function in the context of repeated percutaneous insult by other skin pathogens.     

Antigen-nonspecific suppression of the immune response in mice as affected by pertussis vaccine

A study was made of the suppressorgenic action of killed whole-cell pertussis vaccine prepared from B. pertussis strains 475 and 305. Thymic and splenic lymphocytes of CBA mice 3-7 days following intraperitoneal or intravenous inoculation of pertussis vaccine were shown to inhibit in an antigen-nonspecific manner the plaque-forming cell (PFC) production in the adoptive transfer experiments. Suppression of graft-versus-host reaction was also observed, estimated by the survival of irradiated (CBA X C57BL/6) Fl mice, or by measuring the endogenous colony formation. Suppression-mediating cells were found to be susceptible to complement-dependent lysis by the anti-I-Jk alloantiserum against the specific marker of suppressor T cells, antigen I-J. Furthermore, thymocytes of pertussis vaccine-treated mice were shown to inhibit the endogenous colony formation in syngeneic mice irradiated in sublethal dose. Thus, B. pertussis vaccination of CBA mice resulted in appearance of suppressor T cells that exerted various inhibitory activities in several experimental test-systems.     

Relations between the methods of isolating Brucella lipopolysaccharides and their effect on hemopoiesis in mice

The comparative study of the effect produced by different lipopolysaccharide (LPS) preparations obtained from B. melitensis virulent strain 565 and B. abortus vaccine strain 19-BA on hematopoiesis in mice was made. The LPS preparations were obtained (1) by Boivin's technique, (2) by Westphal's technique and (3) by mild alkaline hydrolysis of Bovin's active complex, this technique having been developed at the Brucellosis Laboratory of the Gamaleya Research Institute of Epidemiology and Microbiology. All tests (the spleen endocolonization test, the hydroxyurea kill test, the determination of the content of splenic colony-forming units in the peripheral blood) showed that LPS from B. melitensis virulent strain 565 had a more pronounced disturbing effect on hematopoiesis than LPS from B. abortus vaccine strain 19-BA. Among the LPS preparations obtained by different methods, the one obtained with the use of the technique developed at the Gamaleya Research Institute of Epidemiology and Microbiology proved to have the mildest effect on hematopoiesis, probably due to the partial saponification of the lipid component of LPS. Lipid A in a dose of 0.1-10 micrograms produced no activating effect on the hematopoiesis characteristics under study. None of the LPS preparations proved to be capable of stimulating the formation of transitory endogenous colonies in the spleen of mice.     

Polyprenyl Phosphates Induce a High Humoral and Cellular Response to Immunization with Recombinant Proteins of the Replicative Complex of the Hepatitis C Virus

The search for new adjuvants remains the critical task for the creation of hepatitis C vaccines due to the weak immunogenicity of biotechnological products. When immunizing mice with the recombinant proteins NS3 and NS5B of the hepatitis C virus (HCV), the adjuvant activity of three immunomodulators was compared. Phosprenyl® on the basis of polyprenyl phosphate (PPP), chemically synthesized analogue of the bacterial cell wall glucosaminyl muramyl dipeptide (GMDP), and IFN-α recombinant protein were tested. GMDP increased the activity of IgG1 antibodies 4–6 times but did not stimulate the production of IFN-γ; IFN-α has not shown any adjuvant properties. The introduction of recombinant HCV proteins together with PPP in low doses increased the activity of IgG2a isotype antibodies 4–7 times and increased IFN-γ secretion 3 times. Thus, it was first shown that PPP polarizes the immune response to Th1-type and is a promising adjuvant for the development of a vaccine against hepatitis C.     

Dynamics of the mechanical properties of drops of biological liquids during drying as a reflection of the features of selfassembly of their components from the nano- to microlevel

It has been shown that the dynamics of the molecular self-assembly of the components of liquids drying in the form of drops on a solid moistened surface contains information about their composition and structure. The physical mechanisms of this phenomenon have been considered. A method of recording this dynamics and retrieving useful information has been suggested. Examples of using this method in medicinal diagnosis and the assessment of the quality of food products, drugs, and liquids of domestic appliance are given.     

Possible role of the T-cells in regulating in situ hematopoiesis

The aim of the study was to reveal the possible role of T cells in the negative regulation of hematopoiesis. The main experimental approach included incubation of bone marrow cells obtained from mice of different strains with the anti-serum against a specific marker of suppressor T cells--antigen I-J. Anti-I-Jk serum-treated cells and cells treated with nontoxic normal mouse serum or non-treated cells (controls) were further incubated with complement and tested for their CFUs content, using Till & McCulloch exocolonization technique. Treatment with anti-I-Jk serum had a stimulating effect on the CFUs colony formation in mice of the appropriate haplotype (CBA, AKR, A/Sn) bearing I-Jk, but not I-Jb (CC57Br) allele. The same results were obtained in transfer experiments using spleen cells; only in this case stimulating effect was observed in 7-8-day CFUs, while with the marrow transplant augmentation it was seen both 7-8 and 11-12 days following grafting. The seeding efficiency of CFUs was not changed after incubation with anti-I-J serum. The data prove that indigenous for the spleen and bone marrow of mice cells expressing I-J determinants are involved in the negative regulation of hematopoiesis in situ.     

The correction action of Phosprenyl and Gamavit on the functional activity of mouse peritoneal macrophages in response to high doses of Staphylococcus aureus alpha-toxin

The study of the functional activity of peritoneal macrophages of BALB/c mice at different stages of the toxic action caused by S. aureus alpha-toxin (ST) was carried out. The analysis of the dynamics of toxic reaction revealed the main critical points of triggering necrotic processes: the first hour and day 2. One hour after the injection of large doses of ST a sharp increase in the process of antigen binding with its subsequent sharp decrease. Simultaneously, a decrease in the activity of the lysosomal enzymes cathepsin D and acidic phosphatase was established, which was indicative of the destabilization of both lysosomal and cellular macrophage membranes. The increase of oxygen metabolism on day 2, together with the release of lysosomal proteases into the extracellular area, correlated with the maximum death rate of mice and served as the main index of the development of necrosis. The prophylactic and therapeutic use of the preparations Gamavit and Phosprenyl revealed their antitoxic activity and capacityfor stimulating the level of natural body resistance.     

Stimulation of the suppressor activity in relation to hematopoietic cells in the mouse thymus as affected by pertussis vaccine

After a single intraperitoneal injection of formalinized whole-cell pertussis vaccine 5374 into CBA mice a drastic depletion of cells in the thymus accompanied by the enhancement of suppressor T-cells production is observed. T-cells inhibit the endogenous and exogenous colony-formation in the spleen by hematopoietic stem cells (CFUs). Treatment of thymus cells with the anti-I-Jk alloantiserum against a specific marker of suppressor T-cells in the presence of complement removes the inhibitory effect on CFUs proliferation and has a stimulatory action on the capacity of the marrow CFUs to form macroscopic hematopoietic colonies in the spleen compared with control ones. These results suggest probable involvement of I-J-bearing suppressor T-cells in the hematopoietic disorders induced by pertussis vaccine.