@article{APS5112,
author = {Song Chen and Deng-ke Yin and Wen-bing Yao and Yi-dan Wang and Yi-ran Zhang and Xiang-dong Gao},
title = {Macrophage receptors of polysaccharide isolated from a marine filamentous fungus Phoma herbarum YS4108},
journal = {Acta Pharmacologica Sinica},
volume = {30},
number = {7},
year = {2016},
keywords = {},
abstract = {Aim: YCP, a novel (1,4)-α-D-glucan, was isolated from the mycelium of the marine filamentous fungus Phoma herbarum YS4108. In this work, we investigated a YCP-binding cellular receptor expressed by macrophages and the intracellular signal transduction pathways involved in YCP-induced macrophage activation.
Methods: Fluorescence-labeled YCP (fl-YCP) was prepared using the CDAP-activation method. Fluorescence confocal laser microscopy and fluorescence-activated cell sorting (FACS) were used to analyze the effect of fl-YCP on macrophages. To characterize the properties of the YCP receptor, carbohydrates and antibodies were used to inhibit the binding of fl-YCP to macrophages. Moreover, we investigated the role of membrane receptors Toll-like receptor 2 (TLR2), Toll-like receptor 4 (TLR4), Toll-like receptor 6 (TLR6) and complement receptor 3 (CR3). We also examined the role of the p38 kinase pathway in mediating nitric oxide (NO) production.
Results: YCP had an in vitro stimulatory effect on the release of NO in macrophage, and fl-YCP can bind directly to receptors on the surface of macrophages in a time- and dose-dependent manner. Competition studies show that LPS, laminarin, anti-TLR4 antibody and anti-CD11b (CR3) antibody could inhibit fl-YCP binding to macrophages. Conversely, mannose, anti-TLR2 and anti-TLR6 antibody could not. Treatment of RAW264.7 cells with YCP resulted in significant activation of p38 in a time-dependent manner. The specific p38 inhibitor SB203580 abrogated YCP-induced NO generation. Treatment of RAW264.7 cells with anti-TLR4 antibody and anti-CR3 antibody significantly reduced YCP-induced NO production and p38 activation.
Conclusion: We have demonstrated that YCP-induced NO production occurs through the TLR4 and CR3 membrane receptors in a p38 kinase-dependent manner in macrophages.},
issn = {1745-7254}, url = {http://www.chinaphar.com/article/view/5112}
}