[Effect of radiation-induced bystander chemosignals of mice on the humoral immune response in spleen and lymph nodes of intact recipients].

The ability of post-radiation (4 Gy) bystander chemosignals (the volatile components of mouse urine) to distantly modulate the humoral immune response to the sheep red blood cells in the spleen and popliteal lymph nodes of intact recipients has been investigated. It was shown that the exposure of animals to chemosignals before antigen injection resulted in the decrease and increase of the immune response in the spleen and lymph nodes, respectively. When animals were exposed to chemosignals after the antigenic stimulus, an increased immune response was observed in both spleen and lymph nodes. The contribution of radiation-induced bystander signaling in the response of socially organized animals to the effect of ionizing irradiation is discussed.

[The influence of postradiation chemical signals of mice on the humoral immune response in recipients in different time relative to antigenic stimulus].

The influence of volatile urine chemosignals of irradiated (4 Gy) mice on the primary humoral immune response to sheep red blood cells in intact recipients was investigated. It was demonstrated that the direction of immunomodulatory effect is dependent upon the time at which the postradiation chemosignals was initially applied. The antibody response to antigen was markedly suppressed in mice that were exposed before antigen injection. When chemosignals applied immediately following inoculation of antigen the antibody response was unaffected. The immune response was increased when chemosignals was loadeded for 1-10 days after immunization. The possible mechanisms of immunomodulation are considered.

[Experimental study of the radioprotective action of melanin on the somatic development during irradiation in the antenatal period of ontogenesis].

Daily introduction per os of the exogenous melanin in a doze of weight of 10 mg/kg pregnant female rats Wistar eliminated the functional deficiency of somatic development revealed at posterity at chronic gamma-irradiation in a doze 1.00-1.25 Gy for all period of pregnancy. The irradiation or introduction melanin antenatal to a phase ontogenesis resulted in stimulation of the immune answer, which was determined at offspring on 3rd week after birth. On the basis of the received data it is concluded presence radioembryoprotective actions melanin in the relation embryotoxic effects of small dozes of ionizing radiation and its participation in regulation immunogenes.

[The inhibiting effect of a low-dose ionizing radiation on the primary humoral immunity in the early period of an postnatal ontogeny].

The single exposition of 3- and 4-week mice in a dose 0.1 Gy resulted in depressing primary T-dependent humoral immune response. Unlike juvenile ones at adult 16-week animals the stimulation antibody-formation took place. As a result of the administration of immunomodulating drugs, thymogene and nucleinate of a sodium in irradiation mice of 3-week age was an augmentation of the number of antibody-producing cells relatively in 2 and 4 times. At the same time at irradiated in dose 0.1 Gy of adult mice thymogene abrogated the stimulating effect of radiation. It is suggested that the probable cause of the immunosuppressing effect of a small dose of radiation can be an inactivation of a radiosensitive subpopulation of helper cells or selective stimulation of the functional activity of neonatal suppressor cells.

[Various approaches to designing the functionally active determinants as illustrated by the influenza virus A(H3N2) hemagglutinin]. / Nekotorye podkhody v konstruirovanii funktsional'no-aktivnykh determinant na primere gemaggliutinina virusa grippa A(H3N2).

Hexapeptide Lys-Gly-Pro-Asp-Ser-Gly analogous to the immunodominant fragment 141-146 of the epitope A of the influenza virus A(H3N2) hemagglutinin is synthesized. Conjugated with thyroglobulin and hemocyanine, the hexapeptide induced formation of highly specific antibodies with heterolytic properties in CBA mice. Antihexapeptide antibodies interact not only with the homologous antigen but also with hemagglutinin and influenza virus. Choice of the hexapeptide sequence is discussed.

[Synthesis of poly (Lys-Ser-Glu) and study of its antigenic and immunogenic properties]. / Sintez poly (Lys-Ser-Glu) i izuchenie ego antigennykh i immunogennykh svoistv.

We have synthesized oligo- and polypeptides containing lysin, serine and glutamic acid residues. Di- and tripeptides were prepared by the successive elongation of C-terminus by means of the N,N'-dicyclohexylcarbodiimide or mixed anhydride methods. The oligopeptides were obtained by block condensation of pentafluorophenyl esters of tripeptides, and polypeptides by polycondensation of dipeptide 2,4,5-trichlorophenyl esters. The three amino acids (Lys, Ser, Glu) were shown to take part in formation of antigenic determinants, serine being probably the immunodominant amino acid, and dipeptide Ser-Glu- the most important component of the epitope Lys-Ser-Glu. Polypeptides (Lys-Ser-Glu)n induced cross-reacting or heteroclitic antibodies. The expression of immune response depended on genotype of experimental animals.

[Synthesis and study of B-nor-8-isoanalogs of steroid estrogens]. / Sintez i issledovanie B-nor-izoanalogov steroidnykh éstrogenov.

The study of the binding of estradiol B-nor-8-isonalogues to estrogen receptors from the rat uterus helped create the proposed model of the corresponding ligand-receptor complexes. The use of this model ensured the choice of such micromodifications in this steroid group that sharply decreased their hormonal activity. By the example of 16,16-dimethyl-D-homo-B-nor-8-isoestrone, we demonstrated the possibility of the synthesis of the estrogen analogues devoid of uterotropic activity but retaining immunosuppressive activity.

[Effect of low doses of ionizing radiation on thymus-dependent humoral immune response and the polyclonal activation of B lymphocytes]. / Vliianie malykh doz ioniziruiushchei radiatsii na timuszavisimyi gumoral'nyi immunyi otvet i poliklonal'nuiu aktivatsiiu B-limfotsitov.

The exposure of mice to low dose of gamma-rays (10 cGy, 1 cGy/min) increased thymus-dependent humoral immune response and polyclonal activation of B-cells. Injection of hydroquinone eliminated radiation-induced augmentation of polyclonal response of B-lymphocyte. Thymogen decreased significantly the radiation-induced immunostimulation. The study of the dynamics of primary immune response showed that the period of radiation-induced elevation was followed by the phase of profound reduction of antibody formation. Possible negative consequences of action of low doses of ionizing radiation on immune system is discussed.

[Separate and combined effects of ionizing radiation and cyclophosphamide on thymus-dependent humoral immune response]. / Razdel'noe i sochetannoe vozdeistvie ioniziruiushcphei radiatsii i tsiklofosfana na timuszavisimyi gumoral'nyi immunnyi otvet.

The total exposure of gamma-irradiation, (1-2 Gy) or intraperitoneally injection of cyclophosphamide (10-50 mg/kg) resulted in the dose-dependent inhibition of humoral immune response. The immunosuppression was expressed to a greater degree in lymphatic nodules, than in spleen. The combined action of these factors showed the effect of synergism. The injection of cyclophosphamide in mice neutralized the effect of antibody genesis induced by low dose irradiation (0.1 Gy).

[Effect of low doses of ionizing irradiation on viability of cortical thymocytes]. / Deistvie ioniziruiushchei radiatsii v diapazone malykh doz na zhiz nesposobnost' kortikal'nykh timotsitov.

The cortical thymocytes of rats in whole organism, isolated lobes of thymus and cells suspension were exposed to ionizing radiation in a wide range of doses (0.1-200 cGy). In contrast to relatively high dose radiation (50-200 cGy), exposure to doses of 10 cGy resulted in cell death without DNA degradation. The level of doses lower than 10 cGy (0.5-5 cGy) induced thymocyte death which is independent of DNA degradation, RNA and protein synthesis. With decrease in radiation dose, the increase of latent period preceding cell death took place.

[Isolated and combined effects of low-level ionizing radiation and hydroquinone on the humoral immunity in the regional lymph nodes]. / Izolirovannoe i sochetannoe vozdeistvie ioniziruiushchei radiatsii v nizkikh dozakh i gidrokhinona na gumoral'nyi otvet v regionarnykh limfaticheskikh uzlakh.

The whole-body exposure of mice to 0.1 Gy gamma-radiation resulted in stimulation of T-cell dependent humoral immune response in lymph nodes. At the same time enhancement of susceptibility of immunocompetent cells to damaging effect of hydroquinone was observed. Under irradiation with doses of 0.5 or 1 Gy which cause dose-dependent immunosuppression, hydroquinone induced stimulation of antigen production.

[The combined effect of ionizing radiation and benzene on immunoreactivity indices in the spleen and lymph nodes]. / Sochetannyi éffekt ioniziruiushchego izlucheniia i benzola na nekotorye pokazateli immunoreaktivnosti v selezenke i limfaticheskikh uzlakh.

Under the influence of the combined action of gamma irradiation (1 Gy, 1,15 Gy/min) and benzene the synergistic reduction of proportion and absolute content of B-cells and less expressed reduction of absolute content T-cells in spleen and lymph nodes was observed. In spleen the thymus-dependent humoral immune response was resistant to combined effect of irradiation and benzene, while in lymph nodes it was highly sensitive. The profound suppression of antibody formation in lymph nodes was characterized by synergism. It was accompanied by the block of specific recruitment of antigen sensitive cells within drained lymph nodes from migrating stream. The suppression of local immune response resulting from the combined effect of radiation and toxicants may be the cause of protective immunity disturbance.

[Immunotoxicity of aluminum chloride]. / Immunotoksichnost' khloristogo aliuminiia.

Aluminum chloride was tested for its effect on primary T-dependent humoral immune response. The administration of aluminum chloride in the genotoxic dose (0.04 M) caused in mice a profound immunosuppressive effect accompanied by diminished thymic and splenic cellularity. The findings suggest that aluminum chloride possesses marked immunotoxic properties.

[Attraktive and aversive for intact individuals volatile excretion of male mice induced a thymus dependent antigen].

Immunization of male mice of the CBA and C57BL/6J strains with sheep red blood cells (SRBC) induce excretion of urinary volatile components (VC), modifying the behavioral reactions of intact males CBA strain. In early times after injection of 1 x 10(8) SRBC per mouse results in secretion of attractive VC, whereas injection of 1 x 10(9) cells per mice induces secretion of aversive VC. Regular for normal and the observed also in the early stages of attraction of intact males CBA to VC immunized syngeneic males CBA (relatively VC immunized with allogeneic C57BL/6) was lost from 3 to 14th day after the introduction of SRBC in the dose of 1 x 10(8) cells/mice and with the 9th on the 14th day after the introduction of SRBC in the dose of 1 x 10(9). The biological significance of the antigen induced chemosignaling in animals is discussed.

[Effect of volatile excretions induced with thymus-dependent antigen in female mice on the behavioural responses of males].

It was found that thymus-dependent antigen sheep red blood cells in the optimal immunogenic dose (1 x 10(8) cells/mouse) induced in female mice of CBA and B6 strain secretion of attractive urinary volatile components (VCs), and in the supraoptimal dose (1 x 10(9) cells/mouse)--aversive VCs for intact males CBA strain. In a direct comparison of the properties ofVCs-immunized mice of CBA and B6, a modification of the effect of constitutive chemosignalling: disturbance of ability of females VCs to attract allogeneic males, was observed. The role of thymus-dependent antigen dose and sex of animals in the mechanism of generation of antigen-induced chemosignals is discussed.