Phagocytic and macropinocytic activity in MARCKS-deficient macrophages and fibroblasts
Phagocytic and macropinocytic activity in MARCKS-deficient macrophages and fibroblasts
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DOI：
10.1152/ajpcell.1999.277.1.c163
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发表时间：
1999-07-01
影响因子：
5.5
通讯作者：
Blackshear, PJ
中科院分区：
文献类型：
--
作者：
Carballo, E;Pitterle, DM;Blackshear, PJ
巨噬细胞表达高水平的肉豆蔻酰化的富含丙氨酸的C激酶底物(MARCKS)，这是一种肌动蛋白交联蛋白。为了研究Marcks在巨噬细胞功能中的可能作用，我们从野生型和Marcks基因敲除的小鼠胚胎中产生了胎肝来源的巨噬细胞。野生型和Marcks缺陷型巨噬细胞在形态(瑞特氏染色)或肌动蛋白分布(罗丹明-鬼臼毒素染色，在基础条件下或经佛波酯、脂多糖或两者处理后)方面没有差异。然后，我们评估了不同受体介导的吞噬功能：用包被抗体的绵羊红细胞检测Fc受体，用C3b包被的酵母检测补体C3b受体，用未调理的酵母多糖检测甘露糖受体，用乳胶珠检测非特异性吞噬功能。我们还使用FITC-葡聚糖对巨噬细胞和小鼠胚胎成纤维细胞的液相内吞作用进行了研究，以定量这一过程。在大多数情况下，来自野生型和Marcks缺陷小鼠的细胞之间没有差异。然而，在45-60分钟内，酵母多糖的吞噬速率有微小但显著且可重复性的差异，Marcks缺陷细胞的吞噬速率较低。我们的数据表明，Marcks缺乏可能导致酵母多糖吞噬速率略有下降。
Macrophages express high levels of the myristoylated, alanine-rich, C kinase substrate (MARCKS), an actin cross-linking protein. To investigate a possible role of MARCKS in macrophage function, fetal liver-derived macrophages were generated from wild-type and MARCKS knockout mouse embryos. No differences between the wild-type and MARCKS-deficient macrophages with respect to morphology (Wright's stain) or actin distribution (staining with rhodamine-phalloidin, under basal conditions or after treatment with phorbol esters, lipopolysaccharide, or both) were observed. We then evaluated phagocytosis mediated by different receptors: Fc receptors tested with IgG-coated sheep red blood cells, complement C3b receptors tested with C3b-coated yeast, mannose receptors tested with unopsonized zymosan, and nonspecific phagocytosis tested with latex beads. We also studied fluid phase endocytosis in macrophages and mouse embryo fibroblasts by using FITC-dextran to quantitate this process. In most cases, there were no differences between the cells derived from wild-type and MARCKS-deficient mice. However, a minor but significant and reproducible difference in rates of zymosan phagocytosis at 45-60 min was observed, with lower rates of phagocytosis in the MARCKS-deficient cells. Our data indicate that MARCKS deficiency may lead to slightly decreased rates of zymosan phagocytosis.