β-1,3-Glucan-Induced Host Phospholipase D Activation Is Involved in Aspergillus fumigatus Internalization into Type II Human Pneumocyte A549 Cells

PLoS One

Martina Schmidt¹  Li Han²  Xuelin Han²  Dongyu Zhen²  Sha Tao²  Rentao Yu² 

[1] Department Molecular Pharmacology, University of Groningen, Groningen, The Netherlands;Department for Hospital Infection Control and Research, Institute of Disease Control and Prevention of PLA, Academy of Military Medical Sciences, Beijing, China

关键词: Aspergillus fumigatus;    Host cells;    Epithelial cells;    Nystatin;    Flow cytometry;    Phagocytosis;    Small interfering RNAs;    Macrophages;   

DOI  :  10.1371/journal.pone.0021468

学科分类：医学（综合）

来源: Public Library of Science

【 摘 要 】

The internalization of Aspergillus fumigatus into lung epithelial cells is a process that depends on host cell actin dynamics. The host membrane phosphatidylcholine cleavage driven by phospholipase D (PLD) is closely related to cellular actin dynamics. However, little is known about the impact of PLD on A. fumigatus internalization into lung epithelial cells. Here, we report that once germinated, A. fumigatus conidia were able to stimulate host PLD activity and internalize more efficiently in A549 cells without altering PLD expression. The internalization of A. fumigatus in A549 cells was suppressed by the downregulation of host cell PLD using chemical inhibitors or siRNA interference. The heat-killed swollen conidia, but not the resting conidia, were able to activate host PLD. Further, β-1,3-glucan, the core component of the conidial cell wall, stimulated host PLD activity. This PLD activation and conidia internalization were inhibited by anti-dectin-1 antibody. Indeed, dectin-1, a β-1,3-glucan receptor, was expressed in A549 cells, and its expression profile was not altered by conidial stimulation. Finally, host cell PLD1 and PLD2 accompanied A. fumigatus conidia during internalization. Our data indicate that host cell PLD activity induced by β-1,3-glucan on the surface of germinated conidia is important for the efficient internalization of A. fumigatus into A549 lung epithelial cells.

【 授权许可】

CC BY