Effect of exogenous progesterone and estradiol on the process of embryonic implantation in lead intoxicated female mice]

Exposure of female mice to high doses of lead from the first day of pregnancy inhibits embryonic implantation. Animals exposed to 0.5% of lead in diet received injections of progesterone and estradiol, from day 4 to day 7 or from day 5 to day 8 of pregnancy. Such treatments induced implantation in respectively 50 and 80% of the mice. In controls, implantation was observed in 60% of the animals. In animals exposed to lead but not hormone-treated, no implantation was observed. The inhibition of implantation caused by lead seems thus to be due mainly to an action of this metal on the hormonal balance of the exposed mother, and this confirms our earlier results.     

Effect of non-steroidal anti-inflammatory agents on interferon induction]

Nonsteroid antiinflammatory agents (NAIA) such as antipyrine, butadion, acetylsalicylic acid, sodium salicylate, stampyrine and 4-iodantipyrine are not interferonogenic. Still, they stimulated interferonogenic action of poly(G).poly(C) in studies on animals. Relation between the interferon-stimulating action of the NAIA and their effect on activity of prostaglandin and the influence on the immune system was suggested.     

Cellular immunologic reactions in mice tolerant to the transplantation antigens after immunization with the cross-reacting microbial antigens]

In combined administration of cyclophosphamide and lymphocytes of mice (CC57BR XX C3H) F1 to mice CC57BR there was observed a tolerance to alloantigens of mice C3H. Immunization of the tolerant mice with the vaccines of streptococcus, group A, and Candida albicans, containing antigens similar to the transplantation ones, led, to the partial destruction of the tolerance. This was expressed in the reduction in the CC57BR mice of the survival of skin allotransplants of mice C3H and the appearance in the lymphoid organs of lymphocytes with the cytotoxic activity against the allogenic target cells. In case of the tolerance destruction the amount of the recipient's lymphocytes forming rosettes with the erythrocytes of mice C3H remained unchanged, but the stem cell count fell in the spleen and the lymph nodes. The total amount of the T- and B-lymphocytes in the lymphoid organs was unchanged in destruction of the tolerance.     

Effect of exogenous ribonucleases on the propagation of Candida tropicalis yeast]

The effect of exogenic microbial and tissue RNAses on the reproduction of Candida tropicalis yeasts were studied. Catalytically active and inactive forms of ribonucleases were shown to stimulate yeast organism reproduction. Using immunochemical and radioisotopic methods, it was found that RNAses penetrated into yeast cell. The correlation between yeast cell penetration by exogenic enzymes and the physiological state of the cells was revealed. The activation of the chromatin associated RNAse-polymerase under the action of the catalytically active binase was observed in in vitro experiments. The mechanisms of the stimulatory effect of catalytically active and inactive RNAses on growth and reproduction of C. tropicalis are discussed.     

Coombs-positive reactions in mice during transplantation of syngeneic tumors

The effect of the growth of syngeneic transplantable tumors on Coombs' positive test in mice was studied. The modification of the hemagglutination test permitting one to minimize the amount of reagents used is described. Tumor transplantation induced Coombs' positive reactions in most recipients. The phenomenon could be observed in 4 murine strains and 6 tumor systems. Sometimes autoimmune reactions occurred before the emergence of palpable tumors. It is concluded that despite the influence of nonspecific factors, the principal cause of autoimmune reactivity is tumor growth. It seems that the appearance of alien "normal" histocompatibility antigens is a characteristic feature of all the tumors; besides, the host response pattern to these antigen is cross-reactive, including autoimmune component. Coombs' positive test may be one of numerous manifestations of such an autoimmune process.     

Bactericidal effects of macrophages of mice treated with interferon]

The preparations of interferon or virus-inhibiting factor produced in L cell (L-IF) and mouse brain (MB-IF) enhanced the killing of Staphylococcus aureus (S.a.) by the mouse peritoneal macrophage. The L-IF, heat-inactivated at 80 degrees or 60 degrees for 30 min., and mock L-IF could not enhance the killing of S.a. The heterologous human and rabbit interferon preparations didn't enhance the bactericidal activity of macrophage. The L-IF didn't have any effect on the release of lysozyme from the macrophages.     

Lymphocyte reactions at early periods after heart transplantation]

The authors determined the quantitative and qualitative composition of the white blood and dehydrogenase activity of lymphocytes in the blood from the afferent and afferent vessels of the transplanted heart at the early postoperative periods in dogs. There was noted a reduction of the lymphocyte count in the blood flowing from the transplanted heart on account of retention of these cells in the transplant, and also an inversion of the mitochondrial dehydrogenases activity due to the lymphocyte contact with foreign antigens of the transplanted heart. A hypothesis is put forward that the inversion mechanism was connected with the lymphocyte functions in the capacity of immunocompetent cells.     

Effect of the interferon inducer tilorone in inbred CBA mice.

Tilorone hydrochloride (200 mg/kg) was administered intragastrically to inbred CBA mice. After 5, 18 and 48 hr the number of circulating leucocytes and peritoneal cells as well as the migration of unstimulated peritoneal cells, the blood corticosteroid level and interferon production were investigated. In spite of the considerable decrease of the number of mononuclear cells in the blood and polynuclear ones in the peritoneal exudate, the drug induced production of circulating interferon and stimulated its synthesis by peritoneal cells. The blood corticosteroid level and the mast cell count in the peritoneal cavity were significantly elevated, but the migration of peritoneal cells in antigen-free medium decreased.     

Effect of tilorone hydrochloride on the lymphoid and interferon responses of athymic mice.

Nude athymic mice, which lack T-lymphocytes and are unable to mount a cellular immune response, failed to develop the lymphopenia so characteristically produced by a 100 mg/kg oral dose of tilorone hydrochloride in normal mice. The antiviral activity detected in athymic mice 18 hr after a 150 mg/kg oral dose of tilorone was significant, although somewhat less than that found in treated normal mice. These findings suggest that tilorone hydrochloride has a specific effect on T-lymphocytes that accounts for its effect on cellular immunity, but that its antiviral activity is not primarily mediated by T-lymphocytes.     

The effect of exogenous alkalization on cytokinetics and on the survival rate of mice with lymphoblastic leukemia]

In mice vaccinated with two forms of lymphoblastic leukaemia and alkalized with intravenous administration of sodium bicarbonate, the survival rate, the extent of leukaemic infiltration and the proliferative capacity of cells in the bone-marrow, thymus, spleen, lymphnodes, liver and lungs were investigated. The survival rate in the TAL leukaemia of the AKR stem producing an endogenous acidosis could be significantly prolonged in a statistical way by alkalization. Yet an accelerated expiring rate could be observed after exogenous alkalization in L-1210 leukaemia of the DBA/2J stem producing an endogenous alkalosis. By means of cytological and impulse-cytophotometrical investigations the exogenous alkalization of both forms of leukaemia could be proved to have a direct bearing on the proliferative kinetics. In TAL leukaemia the leukaemic proliferation was inhibited by the exogenously involved correction of the acid-base balance; in the L-1210 leukaemia, however, the pH disturbances were enhanced, thus accelerating the leukaemic proliferation. Consequently, the disturbances of the acid base balance seem to be an essential cofactor in the leukaemia genesis. The exogenous direction of the acid-base balance may be important as a means of treating leukaemia.