Home
Resources
Publications
Macrophage Internalization of Fungal Beta-Glucans Is Not Necessary for Initiation of Related Inflammatory Responses

Macrophage Internalization of Fungal Beta-Glucans Is Not Necessary for Initiation of Related Inflammatory Responses

Frances McCann, Eva Carmona, Vishwajeet Puri, Richard E Pagano, Andrew H Limper

Infect Immun. 2005 Oct;73(10):6340-9.

PMID: 16177305

Abstract:

Cell wall beta-glucans are highly conserved structural components of fungi that potently trigger inflammatory responses in an infected host. Identification of molecular mechanisms responsible for internalization and signaling of fungal beta-glucans should enhance our understanding of innate immune responses to fungi. In this study, we demonstrated that internalization of fungal beta-glucan particles requires actin polymerization but not participation of components of caveolar uptake mechanisms. Using fluorescence microscopy, we observed that uptake of 5-([4,6-dichlorotriazin-2-yl] amino)-fluorescein hydrochloride-Celite complex-labeled Saccharomyces cerevisiae beta-glucan by RAW macrophages was substantially reduced in the presence of cytochalasin D, which antagonizes actin-mediated internalization pathways, but not by treatment with nystatin, which blocks caveolar uptake. Interestingly, beta-glucan-induced NF-kappaB translocation, which is necessary for inflammatory activation, and tumor necrosis factor alpha production were both normal in the presence of cytochalasin D, despite defective internalization of beta-glucan particles following actin disruption. Dectin-1, a major beta-glucan receptor on macrophages, colocalized to phagocytic cups on macrophages and exhibited tyrosine phosphorylation after challenge with beta-glucan particles. Dectin-1 localization and other membrane markers were not affected by treatment with cytochalasin D. Furthermore, dectin-1 receptors rather than Toll-like receptor 2 receptors were shown to be necessary for both efficient internalization of beta-glucan particles and cytokine release in response to the fungal cell wall component.

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP21811745	5-([4,6-Dichlorotriazin-2-yl]amino)fluorescein hydrochloride		21811-74-5	Price

As a specialist in analytical chemical Products, Alfa Chemistry offers consumers a wealth of raw materials and a full range of technologies and services.

QUICK LINKS

HEADQUARTERS

Tel:

Fax:

Email: