Isolation and functional characterization of a cyst(e)amine-sensitive protein protecting methyl-dithio groups.

We have previously shown that S-methylthio cysteine mixed disulfide and cystamine potently stimulate thiol production and glutathione synthesis of a human T-cell line in SH-poor medium. Here, we describe a simple photometric method for the determination of methylthio-mixed disulfides (MT-groups) and show that liver contains relatively large amount of MT-groups mainly associated with the globulin fractions. At least a part of methylthio (MT-) globulins is in a complex with a heat-stable protein protecting methylthio-groups against reduction and was designated as anti-methylthio factor (AMTF).

Effect of simulated microgravity on the production of IL-12 by PBMCs.

During space flight immunity is altered. This phenomenon is partly due to the microgravity condition itself. Our earlier space experiments (INTERFERON) indicated that microgravity has a significant effect at the cellular level.

Effect of simulated microgravity on human lymphocytes.

During space flight the function of the immune system changes significantly. Several papers reported that postflight the number and the proportion of circulating leukocytes in astronauts are modified (Leach, 1992), the in vitro mitogen induced T cell activation is depressed (Cogoli et al., 1985; Konstantinova et al.

The effect of simulated microgravity conditions on the TNF-alpha production by human PBMCS.

Our earlier space experiments demonstrated that the interferon production of human lymphocytes in microgravity is 4-8 times higher than those of the synchronous ground controls in vitro (Talas et al. 1983). These data suggested that the microgravity has a significant effect on cells.

Interferon production by and radioprotective effect of poly I : C and tilorone in mice exposed to helium alpha irradiation.

Serum interferon production induced by poly I : C and tilorone and their radioprotective effect in mice exposed to He-alpha particles was studied. The results were compared to those observed after exposure of mice to acute 60Co-gamma irradiation. Interferon production induced by poly I : C was depressed by He-alpha irradiation less than that induced by tilorone.