The role of ether-linked glycerophospholipids in cytotoxic T lymphocytes

We determined the contents of ether-linked glycerophospholipids of murine cytotoxic T lymphocytes (CTL) to evaluate their biological functions. After purifying each glycerophospholipid, we prepared diradylglycerobenzoates after hydrolysis with phospholipase C to separate them into three subclasses, 1,2-diacyl-sn-glycero-3-benzoates, 1-O-alkyl-2-acyl-sn-glycero-3-benzoates, and 1-O-alk-1'-enyl-2-acyl-sn-glycero-3-benzoates. The results showed that the membrane of murine CTL consisted of a large amount of ether-linked glycerophospholipids; contents of 1-O-alkyl-2-acyl-sn-glycero-3-benzoates and 1-O-alk-1'-enyl-2-acyl-sn-glycero-3-benzoates in the total phospholipid were 39.3% and 23.7%, respectively. From these results, it is considered that the ether-linked glycerophospholipids of the biological membranes not only contribute to the membrane stability but also exert a tumoricidal effect or induce cell differentiation by releasing ether-linked lipid metabolites.