Skin reaction, inhibition of macrophage migration, and lymphocyte transformation with tuberculin active peptide (TAP) and arabinogalactan obtained from tubercle bacilli

Arabinogalactan purified from heat-killed tubercle bacilli failed to elicit a delayed type of skin reaction and had no ability to induce in vitro lymphocyte blast formation in sensitized guinea pigs. It was, however, inhibitory to migration of bronchoalveolar washing cells by the indirect test, but not by the direct test, and capable of eliciting an immediate type of skin reaction and anaphylaxis when injected into sensitized guinea pigs. Tuberculin active peptide (TAP) was active in all of in vitro and in vivo cell-mediated immune responses, but not in immediate responses.

The relation between the T cells responsible for cell-mediated cytotoxic killing of mastocytoma cells and the helper-cell effect

The relationship between T cells involved in cell-mediated immunity and antibody response of C57Bl/6J mice towards DBA/2 mastocytoma cells was investigated. Spleen cells primed with viable mastocytoma cells demonstrated marked cell-mediated cytotoxicity (CMC) in vitro, but antibody response of these cells to a hapten (TNP) conjugated to the allogeneic tumour cells in vitro was suppressed as compared with that of normal spleen cells. In contrast, spleen cells primed with frozen-thawed mastocytoma cells showed no CMC, but antibody response to the hapten in vitro of these cells was enhanced. C57Bl/6J mice primed with frozen-thawed mastocytoma cells produced more cytotoxic antibody than non-primed mice when immunized with viable mastocytoma cells. These results indicate that T cells involved in cell-mediated immunity and those involved in the antibody response to allogeneic mastocytoma cells are distinct.?222

The effect of ubiquinone-7 and its metabolites on the immune response

The effect of Q-7, its metabolites and related compounds on antibody formation, was investigated. From the determination of passive hemagglutination titer, the stimulation of the antibody formation was observed in the sera of mice dosed with Q-7 and Q acid-II at 3 and 5 weeks after immunization. As the possible mechanism of the stimulation, the enhancement of a phagocytic activity by the reticuloendothelial system was considered. Release of splenic lysosomal enzyme activities in the dosed group was more at 1 week after immunization than that in the control group, whereas it was less at 3 weeks in the dosed group showing the stabilization of the lysosomal membrane.

Immune responses in aged mice: changes of antibody-forming cell precursors and antigen-reactive cells with ageing

The depressed immune response to sheep erythrocytes in young syngeneic irradiated recipients, adoptively restored with splenic cells from old donor mice, was used as an index of the changes in the immunocompentent cells with ageing. The numbers of antibody-forming cell precursors in both spleen and bone marrow appeared to be diminished with ageing. Some reduction of antigen-reactive cells was also observed in old spleens.

Immune responses in aged mice

In the C57BL strain of mice an immune response to sheep red cells was markedly reduced, whereas the response to a bacterial α-amylase was not changed with ageing. This reduction in an immune response was found to result from a decrease in the number of antibody-forming cells, not from a decrease in the amount of antibody synthesized by individual antibody-forming cells. Reduction in the number of antibody-forming cells in aged mice was thought to result from reduction in the number of antigen-sensitive cells.