Mietto L, Boarato E, Toffano G, Bruni A
Fidia Neurobiological Research Laboratories, Abano Terme, Italy.
Biochim Biophys Acta. 1989 Sep 4;1013(1):1-6. doi: 10.1016/0167-4889(89)90119-5.
Energy-dependent, protein-mediated incorporation of radiolabeled phosphatidylserine vesicles is observed in casein-elicited rat peritoneal cells. Cell fractionation and a comparison with other phospholipids demonstrate the selective interaction of phosphatidylserine with the mononuclear fraction of these cells. During 60 min of incubation, unchanged phosphatidylserine accumulates in the cells whereas lysophosphatidylserine is released in the medium. When adherence is used to fractionate the mononuclear cells, phosphatidylserine uptake is detected in the macrophage-enriched fraction (adherent cells) and in the lymphocyte-enriched fraction (non-adherent cells). Evidence of stereoselective uptake and of phosphatidylserine internalization in both cells is obtained by the use of phosphatidyl-D-serine and by digestion of the extracellular phospholipid with phospholipase A2. Only in lymphocytes is the uptake of phospholipid substantially inhibited by cytochalasin B, metabolic poisons and a low incubation temperature (17 degrees C). Phosphatidylserine deacylation-reacylation is instead detected in both cells. It is concluded that lymphocytes actively concur in the uptake of phosphatidylserine by rat mononuclear cells.
在酪蛋白诱导的大鼠腹膜细胞中观察到能量依赖、蛋白质介导的放射性标记磷脂酰丝氨酸囊泡的掺入。细胞分级分离以及与其他磷脂的比较表明磷脂酰丝氨酸与这些细胞的单核部分存在选择性相互作用。在孵育60分钟期间，未改变的磷脂酰丝氨酸在细胞中积累，而溶血磷脂酰丝氨酸释放到培养基中。当利用贴壁法对单核细胞进行分级分离时，在富含巨噬细胞的部分（贴壁细胞）和富含淋巴细胞的部分（非贴壁细胞）中均检测到磷脂酰丝氨酸的摄取。通过使用磷脂酰-D-丝氨酸以及用磷脂酶A2消化细胞外磷脂，获得了两种细胞中立体选择性摄取和磷脂酰丝氨酸内化的证据。只有淋巴细胞中磷脂的摄取会被细胞松弛素B、代谢毒物和低温孵育（17℃）显著抑制。相反，在两种细胞中均检测到磷脂酰丝氨酸的脱酰基-再酰基化。得出的结论是，淋巴细胞积极参与大鼠单核细胞对磷脂酰丝氨酸的摄取。
