Journal of Cell Science 115, e1202-e1202 (2002)
© 2002 The Company of Biologists Limited
Lipid rafts in innate immunity
Lipid rafts — ordered membrane microdomains rich in
glycosphingolipids and cholesterol — are implicated in both membrane
sorting and signal transduction. In the acquired immune response, they appear
to play an important role in T-cell activation, serving as platforms for
assembly of the signalling machinery. Kathy Triantafilou and co-workers now
show that rafts also function in innate immune recognition (see
p. 2603). They demonstrate
that several proteins involved in the cellular response to bacterial
lipopolysaccharide (LPS) exist in lipid rafts: the GPI-linked LPS receptor
CD14 and the heat shock proteins Hsp70 and Hsp90 are permanently present in
rafts, and chemokine receptor 4 (CXCR4), growth differentiation factor 5
(GDF5) and Toll-like receptor 4 (TLR4) enter rafts after stimulation of cells
by LPS. The authors also demonstrate that agents that disrupt raft integrity
(e.g. nystatin) block LPS-induced secretion of tumour necrosis factor 
(TNF-). They therefore conclude that that concentration of signalling
molecules involved in transducing LPS-recognition signals in lipid rafts is
required for an effective innate immune response to pathogenic bacteria
bearing this molecule.
Related articles in JCS:
- Mediators of innate immune recognition of bacteria concentrate in lipid rafts and facilitate lipopolysaccharide-induced cell activation
- Martha Triantafilou, Kensuke Miyake, Douglas T. Golenbock, and Kathy Triantafilou
JCS 2002 115: 2603-2611.
[Abstract]
[Full Text]
