Activation of murine lymphocytes by 2-mercapto-ethanol and related thiol compounds and its mechanism. II. Effect of thiol compounds on the viability of the lymphocytes under a cystine-deficient culture condition.
When murine lymphocytes were cultured in a cystine-deficient RPMI-1640 medium containing 10% fetal calf serum, approximately 70% of the cells died in 48 h. In the presence of 5 X 10(-4) M L-cystine, 70-80% of the lymphocytes remained viable under the same condition. The decrease of the viability was also effectively inhibited when cystine was replaced by the following thiol compounds; 2-mercaptoethanol (2-ME), dithiothreitol (DTT), cysteamine and glutathione (GSH). Oxidized DTT, an intramolecular disulfide that was resistant to the reduction by the lymphocytes, did not show a protective effect in contrast to DTT. On the other hand, 2-hydroxyethyldisulfide was readily reduced to 2-ME by the lymphocytes and improved lymphocyte viability as effectively as 2-ME. These observations suggest that thiol groups are responsible for the improvement of lymphocyte viability under a cystine-deficient condition. The viabilities of both T cells and B cells were equally improved by 2-ME. The intracellular level of GSH remained constant in the presence of cystine but dropped rapidly in its absence. 2-ME could not reverse this decrease of GSH level. These protective effects of thiol compounds on lymphocyte viability are discussed in relation to their capacities to activate murine lymphocytes.
D000818:Animals; D002478:Cells, Cultured; D003553:Cystine / Q000172:deficiency*; D004912:Erythrocytes / Q000502:physiology; D005260:Female; D005978:Glutathione / Q000378:metabolism; D008213:Lymphocyte Activation / Q000187:drug effects*; D008623:Mercaptoethanol / Q000494:pharmacology*; D051379:Mice; D008807:Mice, Inbred BALB C; D013154:Spleen / Q000166:cytology; D013438:Sulfhydryl Compounds / Q000494:pharmacology*
D013438:Sulfhydryl Compounds; D003553:Cystine; D008623:Mercaptoethanol; D005978:Glutathione