Differential roles of CD36 and alphavbeta5 integrin in photoreceptor phagocytosis by the retinal pigment epithelium.
Differential roles of CD36 and alphavbeta5 integrin in photoreceptor phagocytosis by the retinal pigment epithelium.
复制标题
DOI：
10.1084/jem.194.9.1289
复制
发表时间：
2001-11-05
期刊：
影响因子：
--
通讯作者：
Silverstein RL
中科院分区：
文献类型：
--
作者：
Finnemann SC;Silverstein RL
视网膜色素上皮（RPE）细胞采用αVβ5整合素和CD36受体到吞噬细胞光感受器的外部段片段（OS）。 . Early, CD36 antibodies had no effect on OS binding or internalization. Both control and CD36 antibody treated RPE initiated internalization approximately 2 hours after OS challenge. Later, bivalent CD36 IgG accelerated OS engulfment while monovalent Fab fragments inhibited engulfment. Cross-linking Fab fragments恢复了完整的IgG的加速度，即使添加到已经由RPE结合的OS中，抗体也是有效的在顶端或基本RPE表面的连接部分取代了内在化所需的固体因子，但在RPE顶部的结合中，我们的结果表明CD36结扎是必要的，足以激活RPE的OS内部化机制表明CD36在RPE吞噬作用的后结构步骤中充当信号分子，独立于OS结合受体αVβ5整合素。
Retinal pigment epithelial (RPE) cells employ αvβ5 integrin and CD36 receptors to phagocytose photoreceptor outer segment fragments (OS). We explored special properties of RPE phagocytosis to identify the contribution of CD36 to RPE phagocytosis measuring effects of CD36 antibodies on OS binding and internalization kinetics. Early, CD36 antibodies had no effect on OS binding or internalization. Both control and CD36 antibody treated RPE initiated internalization approximately 2 hours after OS challenge. Later, bivalent CD36 IgG accelerated OS engulfment while monovalent Fab fragments inhibited engulfment. Cross-linking Fab fragments restored the accelerating activity of intact IgG. Strikingly, antibodies were effective even if added to OS already bound by RPE. αvβ5 blocking antibody reduced OS binding equally well in the presence of CD36 antibodies but CD36 antibodies accelerated internalization of remaining bound OS. Furthermore, CD36 ligation at either apical or basal RPE surface partially substituted for soluble factors that are required for internalization but not for binding of OS at the RPE apical surface. Our results demonstrate that CD36 ligation is necessary and sufficient to activate the OS internalization mechanism of RPE. They suggest that CD36 acts as a signaling molecule in postbinding steps of RPE phagocytosis independently of the OS binding receptor αvβ5 integrin.
登录
查看更多内容
DOI：
10.1083/jcb.138.3.707
发表时间：
1997-08-11
期刊：
The Journal of cell biology
影响因子：
--
作者：
Dawson DW;Pearce SF;Zhong R;Silverstein RL;Frazier WA;Bouck NP
通讯作者：
Bouck NP
影响因子：
56.9
作者：
LAVAIL, MM
通讯作者：
LAVAIL, MM
影响因子：
3.4
作者：
EDWARDS, RB
通讯作者：
EDWARDS, RB
影响因子：
56.9
作者：
EDWARDS, RB;SZAMIER, RB
通讯作者：
SZAMIER, RB
影响因子：
3.5
作者：
D'Cruz, PM;Yasumura, D;Vollrath, D
通讯作者：
Vollrath, D