Effect of hyperlipidemia on thymocyte sensitivity to apoptosis in CBA and C57B1/6 mice

Effects of experimental hyperlipidemia on apoptosis and proliferation of thymocytes in response to mitogens were studied in CBA and C57B1/6 mice. The concentrations of cholesterol in the serum and thymocyte membranes increased in both mouse strains. Spontaneous and dexamethasone-induced apoptosisin vitro and the proliferative response to phytohemag-glutinin and concanavalin A were enhanced in thymocytes from C57B1/6 mice and suppressed in cells from CBA mice. These data suggest opposite reactions of thymocyte to increased serum cholesterol concentration in these two strains, associated with stimulation and suppression of cell activity. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 130, No. 8, pp. 200–202, August, 2000     

Beneficial effect of Salmonella typhimurium infection and of immunoglobulins from S. typhimurium-infected mice on the autoimmune disease of (NZB × NZW)F1 mice

Various infections can precede or aggravate autoimmune diseases. Yet a beneficial effect of infection has also been described and various mechanisms have been postulated to explain this effect. The aim of this study was to examine the hypothesis that infection can have an immunoregulatory effect on the autoimmune process via the increased production of natural polyreactive antibodies. The effect of Salmonella typhimurium infection on the lupus-like disease of (NZB × NZW)F₁ (B/W) mice was therefore studied. The effect of IgM and IgG preparations isolated from the serum of S. typhimurium-infected C57Bl/6 and CBA mice on the autoimmune disease of B/W mice was also tested. C57Bl/6 and CBA mice were chosen because they are respectively genetically susceptible and resistant to S. typhimurium infection and they differ in their antibody response during the early phase of infection. CBA mice can mount a specific anti-bacterium antibody response, whereas C57Bl/6 mice present increased production of polyreactive antibodies. The infection effect was evaluated on several disease parameters, i.e. survival, incidence of high grade proteinuria and serum IgM and IgG antibody activity directed against a panel of autoantigens. Our main findings were: (i) infection of B/W mice with an attenuated strain of S. typhimurium delayed the course of the autoimmune disease when performed before the appearance of autoimmune symptoms; and (ii) IgM and IgG preparations from S. typhimurium-infected C57Bl/6 mice had a similar effect, whereas the IgM and IgG preparations from infected CBA mice, as well as from normal C57Bl/6 and CBA mice, were ineffective. These results suggest that S. typhimurium infection can beneficially influence the development of the autoimmune disease of B/W mice. The immunoregulatory effect of the infection seems to be related, at least partially, to the increase of a particular population of antibodies, the polyreactive antibodies.     

Comparison of the specific binding of 17β-estradiol with receptor proteins in the cytosol fraction of uteruses of CBA and C57Bl/6 mice in the course of 1,2-dimethylhydrazine-induced carcinogenesis

The level of specific binding and affinity of 17β-estradiol for receptors in the cytosol fraction of uteruses of CBA and C57Bl/6 mice exposed to 1,2-dimethylhydrazine for a long time was studied. Estrogen receptors were studied by separating free and receptor-bound hormone with dextran-coated carbon. The theoretical number of sites of ligand binding with receptor protein and the level of free binding sites were shown to be higher in CBA mice sensitive to carcinogenesis induction in comparison with C57Bl/6 mice resistant to the carcinogen effect in both the experimental and control groups over the course of the experiment. The ligand affinity for receptor protein was more or less the same in all the groups. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 1, pp. 58–62, January, 1995 Presented by N. N. Trapeznikov, Member of the Russian Academy of Medical Sciences     

Effect of hyperlipidemia on functional activity of peritoneal macrophages in CBA and C57Bl/6 mice

The effect of experimental hyperlipidemia on functional activity of macrophages was studied in CBA and C57Bl/6 mice resistant and sensitive to the formation of aorta lesions, respectively. Two-month atherogenic diet increased the content of cholesterol in the serum and cells of peritoneal exudate in mice of both strains. In parallel, production of nitrites and 5'-nucleotidase activity in peritoneal macrophages increased, while parameters of phagocytosis, pinocytosis, and NBT test remained unchanged. Changes in the state of macrophages can be explained by increased cholesterol content. The absence of differences in functional activity of macrophages in CBA and C57Bl/6 mice indicates that the observed shifts are insignificant for the development of fatty streaks in the aorta.     

Elevated basal activity of tryptophan oxygenase in alcohol-preferring C57Bl mice

Tryptophan oxygenase activity in alcohol-preferring C57Bl mice and control CBA and DBA/2 mice was studied under nonstressful conditions and after glucocorticoid-induced stress. Elevated basal tryptophan oxygenase activity in C57Bl mice is probably responsible for reduced brain content of tryptophan and serotonin associated with alcohol preference. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 4, pp. 408–410, April, 2000     

Effect of dioxydine and cyclophosphane on lipid peroxidation and superoxide dismutase and catalase activities in C57Bl/6 and BALB/c mice

Twenty-four hours after intraperitoneal injection of cyclophosphane (40 mg/kg) and dioxydine (300 mg/kg) to C57Bl/6 mice, liver catalase activity dropped by 29 and 23%, respectively. In BALB/c mice, dioxydine (but not cyclophosphane) reduced catalase activity by 24%. Superoxide dismutase activity was lowered by cyclophosphane (but not dioxydine) in BALB/c mice, and by both dioxydine and cyclophosphane in C57Bl/6 mice (by 24 and 86%, respectively). The level of 2-thiobarbituric acid (TBA)-reactive lipid peroxidation (LPO) products in the liver of BALB/c mice treated with cyclophosphane and dioxydine increased 1.4- and 2.1-fold, respectively, while in C57Bl/6 mice it did not differ from the control. The initial rate ofin vitro-induced LPO in BALB/c mice receiving cyclophosphane and dioxydine increased 1.5- and 4-fold, respectively. In C57Bl/6 mice both cyclophosphane and dioxydine inhibited the accumulation of TBA-reactive LPO products. On the whole, animals of the C57Bl/6 strain are more resistant to the LPO-inducing action of mutagens than BALB/c mice, despite the fact that the latter are characterized by a higher activity of antioxidant enzymes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 5, pp. 528–532, May, 1996     

Rate of development of immunological memory and characteristics of the secondary immune response in mice of strains with high and low reactivity

Immunological memory for sheep's red blood cells develops in mice of strains CBA and DBA/2 and (CBA×C57BL/6)F₁ hybrids 24 h after injection of a small dose of the antigen, but 48 h after injection in C57BL/6 mice. The level of the secondary immune response in CBA, C57BL/6 and F₁ hybrids is significantly higher than in DBA/2 mice. Maximal production of antibody-forming cells in the spleen of the CBA mice is observed after two injections of small doses of the antigen. By contrast to this, to obtain a marked immune response in the case of adoptive transfer of spleen cells of C57BL/6 mice a second injection of a large dose of antigen is required.Laboratory of Immunogenetics, Institute of Medical Genetics, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. H. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 10, pp. 454–457, October, 1977.     

Interstrain peculiarities of the secondary immune response in mice

CBA, CC57BR, C57B1/6, BALB/c, and outbred white mice were intraperitoneally or subcutaneously (C57B1/6 strain) immunized with sheep red cells in a dose optimal for the development of delayed-type hypersensitivity but subthreshold for antibody production. Seven days later the mice were reimmunized with sheep red cells in various doses subcutaneously (CBA, C57B1/6, BALB/c, outbred mice) or intraperitoneally (CBA, CC57BR, outbred mice), and 5 days after reimmunization the intensity of antibody production and delayed-type hypersensitivity was assessed. Intact mice were controls. The immunization was found to selectively enhance delayed-type hypersensitivity in C57B1/6, CC57BR, and BALB/c mice and to intensify antibody production in CBA mice; both phenomena were observed in outbred mice. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 11, pp. 499–501, November, 1994 Presented by K. P. Kashkin, Member of the Russian Academy of Medical Sciences     

In vivo cytogenetic effects of acrylamide, acrylonitryl, and their combination with verapamil

Acrylamide significantly increased the number of cells with chromosome aberrations in BALB/c and C57B1/6, but not in CBA mice. No difference was found between the BALB/c and C57B1/6 strains in the clastogenic effect of acrylamide. Within the studied concentration range acrylonitrile exerted no genotoxic effects. Verapamil significantly potentiated the clastogenic effect of acrylamide in BALB/c mice, while in C57B1/6 mice potentiation was observed only after the repeated intragastric administration of verapamil in a dose of 2.5 mg/kg. Acrylonitrile in combination with verapamil also produced a slight clastogenic effect after single and repeated administrations. Thein vivo comutagenic activity of verapamil depended on the dose, administration route and schedule, and genotype of experimental animals. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 128, No. 12, pp. 684–689, December, 1999     

Syngeneity as a factor in cooperation between T- and B-lymphocytes

Effectiveness of cooperation between (CBA x C57BL/6)F₁ thymocytes and CBA bone-marrow cells in the immune response to sheep's red cells was compared with syngeneic combinations of the same cells in culturein vivo. The selectiveness of cooperation between T- and B-lymphocytes of different origin also was investigated in incomplete (CBA x C57BL/6)F₁CBA chimeras obtained with the aid of cyclophosphamide, in which the donors were primed with sheep's red cells and the recipients were either intact or were tolerant to that antigen. F₁ T-cells were shown to cooperate with CBA B-cells 10–50 times less effectively than with syngeneic B-cells. It is postulated that the similar antigenic structure of the cell membrane of T- and B-lymphocytes, acting in conjunction with their physical contact, increases the effectiveness of action of the T-mediator on the B-cellLaboratory of Immunological Tolerance, N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR O. V. Baroyan.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 3, pp. 325–327, March, 1976.     

Dextran sulfate sodium-induced colitis generates a transient thymic involution--impact on thymocyte subsets

One of the most widely used animal models for inflammatory bowel disease (IBD) is the dextran sulfate sodium (DSS)-induced colitis. We have previously reported that 5 days administration of DSS in C57Bl/6J mice induces a colonic inflammation that progresses into chronicity after DSS removal, whereas in BALB/cJ mice the inflammation resolves within 4 weeks post-DSS. Here we show that both thymic size and thymocyte numbers dramatically decreased in the acute phase of inflammation in C57Bl/6 mice, 7 days after DSS withdrawal. Mature, CD4(+) and CD8(+) single positive (SP) CD69(lo) CD62L(hi) thymocytes were enriched in these mice, accompanied by a major decrease in the number of immature double positive (DP) thymocytes. However, the different maturation stages within the DP thymocyte subset were unchanged between healthy and inflamed C57Bl/6J mice. Interestingly, as the inflammation progressed into the chronic phase, the thymus recovered and 2 weeks after the acute inflammatory phase all the thymic parameters investigated in this study were restored to normal. In contrast, BALB/cJ mice only develop mild thymic alterations. Nevertheless, we found that within the double negative (DN) thymocytes an increased frequency and also total numbers of CD44(+) CD25(-) (DN1) cells correlated with the severity of colitis, and that the frequency of CD44(-) CD25(-) (DN4) thymocytes decreased proportionally in the acute phase in BALB/cJ mice. Our observations suggest that the thymic effects are intimately connected to the intestinal inflammatory response in colitis regardless of the inflammatory stimuli.     

A secondCandida albicansresistance gene (Carg2) regulates tissue damage, but not fungal clearance, in sub-lethal murine systemic infection

The severity of systemic infection with the yeastCandida albicanshas been shown to be under complex genetic control. C57/L mice carry an allele that is associated with an increase in tissue destruction when compared with C57Bl/6 mice; however, the gene affects only the severity of tissue lesions, and does not influence the magnitude of the fungal burden in either kidney or brain. Studies in [C57/L×C57Bl/6]F1 hybrid mice, and [C57/L×C57Bl/6]F1×C57/L backcross mice, demonstrated that the gene behaves as a simple Mendelian co-dominant.     

Immunity Parameters in Mice of Different Strains

Quantitative composition and functional activity of immunocompetent cells differ in mice of different strains. The counts of T cells in the bone marrow and spleen, proliferative activity of T cells in the spleen, levels of IL-2 and IL-10 production by splenic T cells, number of antigen-specific T cells and their functional activity are low in C57Bl/6, BALB/c, and CC57W mice and high in CBA/CaLac, DBA/2, and C3H animals. Low phagocytic activity of peritoneal macrophages was detected in BALB/c and CC57W mice and high activity in C3H animals. The content of antibody-producing cells in the spleens of C57Bl/6, BALB/c, and CC57W mice is higher than in CBA/CaLac, DBA/2, C3H, A/SN, and AKR/JY mice. Functional activity of B cells is lower in BALB/c and CC57W compared to CBA/CaLac and DBA/2 mice. __________ Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 140, No. 8, pp. 189–191, August, 2005     

Postirradiation volatile secretions of mice: Syngeneic and allogeneic immune and behavioral effects

The immune response in immunologically and olfactorily high- and low-reactive CBA and C57Bl/6 mice is almost similarly decreased after exposure to volatile secretions of syngeneic animals exposed to ionizing radiation in a dose of 4 Gy. In the preference/avoidance test intact animals prefer secretions of irradiated syngeneic and allogeneic animals to those of intact animals, while without irradiation animals of both strains prefer syngeneic secretions. C57Bl/6 mice differ from CBA animals by lower sensitivity.Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 138, No. 10, pp. 432–434, October, 2004     

Selection of anxious mice by a three-stage test in an elevated T-maze

Daily testing of SHR and C57Bl/6 mice during 3 days shows an increase of the number of mice with a high level of anxiety, which was determined according to the ratio of the number of entries into the light arms to the total sum of entries into the light and dark arms of an elevated T-maze. Such results were obtained after 3 testings every 3 days in C57Bl/6 but not in SHR mice. This procedure is proposed for the selection of anxious individuals as objects for an anxiety model. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 355–356, March, 1996 Presented by S. N. Golikov, Member of the Russian Academy of Medical Sciences     

Effects of zoosocial conflict on immunological reactivity of C57Bl/6 mice

In aggressive C57Bl/6 mice, the immune response is shown to be enhanced after 20 confrontations with submissive mice. In submissive mice, the response is inhibited after 10–20 confrontations with aggressive partners. It is concluded that stimulation and inhibition of the immune response are associated with the formation of a neurochemical set which is dopaminergic in aggressive mice and serotoninergic in submissive ones. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, No. 11, pp. 541–543, November, 1996     

Effect of transplantation of lymphocytes and bone marrow cells on immune response during immunization of mice with low or high reactivity to the antigen

Mice of strains C57BL and CBA, with low and high reactivity respectively to immunization with sheep's red cells, received injections of syngeneic lymphocytes or bone marrow cells. Transplantation of syngeneic cells into C57BL mice increased the production of cells forming antibodies against sheep's red cells, but had a depressant effect in CBA mice. The different effects of transplantation of lymphocytes and bone marrow cells on the immune response, depending on the recipient's genotype, are discussed.Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 3, pp. 335–337, March, 1976.     

Postirradiation volatile secretions of mice: syngeneic and allogeneic immune and behavioral effects

The immune response in immunologically and olfactorily high- and low-reactive CBA and C57Bl/6 mice is almost similarly decreased after exposure to volatile secretions of syngeneic animals exposed to ionizing radiation in a dose of 4 Gy. In the preference/avoidance test intact animals prefer secretions of irradiated syngeneic and allogeneic animals to those of intact animals, while without irradiation animals of both strains prefer syngeneic secretions. C57Bl/6 mice differ from CBA animals by lower sensitivity.Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 138, No. 10, pp. 432–434, October, 2004     

Cytomegalovirus hepatitis: characterization of the inflammatory infiltrate in resistant and susceptible mice.

Mice susceptible and resistant to murine cytomegalovirus (MCMV) were infected with this virus and livers were harvested after 2-231 days. Cryostat sections were stained to visualize cells bearing CD4, CD8 or Mac-1 antigens. Mac-1+ cells were prevalent in inflammatory foci after 2 days. These cells persisted in susceptible BALB/c and A/J mice, but disappeared from livers of resistant C57Bl/6 and CBA/CaH mice by day 28. T cell inflammation peaked on days 7-11. This declined by day 56 in C57Bl/6 and CBA/CaH mice, but persisted in BALB/c and A/J mice for at least 231 days. Persistent CD8+ cells were dispersed throughout the parenchyma. More CD8+ cells were observed 7-14 days after infection in the livers of bg/bg (natural killer (NK) cell-deficient) C57Bl/6 and CBA mice, and in C57Bl/6 mice depleted of NK1.1 cells by MoAb. Thus, mice of strains susceptible to MCMV exhibit hepatitis characterized by persistence of dispersed CD8+ cells. This phenomenon may be limited by NK cells in resistant strains.     

Formation of SiO2-induced granulomas in mice of various strains

Peculiarities of SiO₂-induced granulomas in the liver and subcutaneous fat were studied in C57B1/6, CBA/Lac, BALB/c, C57BR, and C3H/F mice. Infiltrative and fibrogenic responses were interrelated and strain-specific primarily due to various intensities of myelopoiesis. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 1, pp. 20–24, January, 2000