Platelet-activating factor (PAF): signalling and adhesion in cell-cell interactions.
Signalling by PAF is closely linked to adhesive interactions between cells of the inflammatory and vascular systems. It acts as a juxtacrine signal that alters the activity of beta 2 integrins on myeloid leukocytes (Figure 1), and works in concert with P-selectin at the surfaces of endothelial cells (Figure 2 and text). Observations in models of flow and in vivo support the original experiments using cultured endothelium under static conditions that indicated that PAF acts at this vascular interface. P-selectin modifies and integrates signals delivered through the PAF receptor on monocytes (Figure 4). Adhesion via P-selectin and engagement of beta 2 integrins modify signals leading to PAF synthesis (text and Figure 5). The intimate relationship between adhesive events and signalling by PAF may be a critical determinant in its roles in physiologic and pathologic responses.
Zimmerman
G A
GA
Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, Utah.
Elstad
M R
MR
Lorant
D E
DE
Mclntyre
T M
TM
Prescott
S M
SM
Topham
M K
MK
Weyrich
A S
AS
Whatley
R E
RE
D000818:Animals; D002448:Cell Adhesion / Q000502:physiology*; D002450:Cell Communication / Q000502:physiology*; D006801:Humans; D007365:Intercellular Junctions / Q000502:physiology; D010972:Platelet Activating Factor / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*
D010972:Platelet Activating Factor