摘要
本实验通过磷脂酰胆碱／胆固醇（ＰＣ／Ｃｈ）摩尔比不同的小单片层人工脂双层膜（ＳＵＶ）与淋巴细胞孵育，将外源性ＰＣ和Ｃｈ导入淋巴细胞，进而研究膜脂质结构改变对淋巴细胞跨膜膜电位及细胞功能的影响。结果显示：①ＣｏｎＡ刺激能诱导淋巴细胞超极化，用ＳＵＶｓ改变膜脂质结构可显著影响细胞跨膜膜电位，其中胞浆膜胆固醇含量是一重要决定因素；②２０μｍｏｌ／Ｌ异博定阻断Ｃａ２＋通道后可消除ＳＵＶｓ处理ＣｏｎＡ诱导的超极化反应。③人工膜作用后淋巴细胞胞浆膜磷脂（ＰＬ）／Ｃｈ比降低，ＣｏｎＡ活化４８ｈ细胞增殖转化功能增强，Ｇ２＋Ｍ期细胞增多，但过多胆固醇则使细胞超极化反应和分裂能力降低。推测膜脂质组成及相关的生物物理特性可能在细胞跨膜信号传递。
In this study, a serial of artificial membranes known as small unilaminar vesicles(SUVs) composed of various phosphatidylcholine(PC)/cholesterol(Ch) molar ratios were constructed, and external PC and Ch were transferred into the human peripheral blood lymphocytes by incubating the SUVs with these cells. Furthermore, the influence of lipid composition on membrane potential and lymphocyte function were investigated. It was showed that:1.ConA stimulation initiated a hyperpolarized reaction in lymphocytes. Membrane potential could be affected by changing the lipid environment of the surface membrane with SUVs, in which the cholesterol content of plasma membrane was a major determinant. 2.20μmol/L verapamil could eliminate the hyperpolarized reaction induced by ConA stimulation after SUVs treatment. 3.ConA stimulating on lymphocytes for 48h increased the percentage of G2+M phase cells and blast transformation of lymphocytes with the decline of phospholipids(PL)/Ch ratios of plasma membrane, but excessive Ch in membrane after treating with SUVs (PL/Ch=1.211) decreased the ability of blast transformation. In conclusion, lipid composition and relative biophysical properties appear to play an especially critical role in modulating the signal receive, signal transduction and blast transformation.
出处
《免疫学杂志》
CAS
CSCD
北大核心
1996年第3期172-176,共5页
Immunological Journal
关键词
膜脂质
胆固醇
膜电位
淋巴细胞
Membrane lipids, Cholesterol, Membrane potential, Lymphocyte
