open access

https://hdl.handle.net/2115/43975

The diacylated lipopeptide FSL-1 enhances phagocytosis of bacteria by macrophages through Toll-like receptor 2-mediated signaling pathway

英語

macrophage

2007-02-22

Blackwell

FEMS immunology and medical microbiology

49

398-409

Enormous lines of evidence have been accumulated that Toll-like receptors (TLRs) function as sensors for microbial invasion. However, less is known about how signaling triggered by TLRs leads to phagocytosis of pathogens. This study was designed to determine whether stimulation of TLR2 with mainly the lipopeptide FSL-1 plays a role in phagocytosis of pathogens by macrophages. FSL-1 markedly enhanced phagocytosis of E. coli more strongly than that of S. aureus, but did not enhance phagocytosis of latex beads. FSL-1 stimulation resulted in enhanced phagocytosis of bacteria by macrophages from TLR2+/+mice but not those from TLR2-/- mice. Chinese hamster ovary cells stably expressing TLR2 failed tophagocytose these bacteria, but the cells expressing CD14 did. FSL-1 induced upregulation of the expression of phagocytic receptors including MSR1, CD36, DC-SIGN and Dectin-1 in THP-1 cells.Human embryonic kidney 293 cells transfected with DC-SIGN and MSR1 phagocytosed these bacteria. These results suggest that the FSL-1-induced enhancement of phagocytosis of bacteria by acrophages may be explained partially by the upregulation of scavenger receptors and the C-type lectins through TLR2-mediated signaling pathways and that TLR2 by itself does not function as a phagocytic receptor.

学術雑誌論文

Accepted Manuscript

0928-8244

1574-695X

AA10879949