TY - JOUR
T1 - Binding of endotoxin to macrophages; interactions of spin-labelled saccharide residues
AU - Jackson, Simon K.
AU - James, Philip E.
AU - Rowlands, Christopher C.
AU - Mile, Bryn
PY - 1992/6/10
Y1 - 1992/6/10
N2 - The molecular mechanisms of endotoxin action are poorly understood. A prerequisite to cellular activation by this agent must be interaction (binding) with the plasma membrane. In this study we have investigated the role of the polysaccharide region of endotoxin (LPS) in binding to macrophages and macrophage-like cell lines. The LPS molecules, from Escherichia coli O111.B4, J5 and the lipid-A, were spin labelled with 2,2,6,6-tetramethylpiperidine-N-oxyl (Tempo) free radical in their sugar residues, and examined by electron spin resonance spectroscopy. This is the first report of the synthesis of spin-labelled endotoxins. Measurement of the rotational correlation times (Tc) indicated that the saccharide residues do not bind to membrane surface structures and suggests that the binding of LPS to macrophages is mediated by the lipid acyl chains. Anti-sera to LPS from E. coli O111.B4 was effective in binding to the polysaccharide of the same LPS bound to the cell surface.
AB - The molecular mechanisms of endotoxin action are poorly understood. A prerequisite to cellular activation by this agent must be interaction (binding) with the plasma membrane. In this study we have investigated the role of the polysaccharide region of endotoxin (LPS) in binding to macrophages and macrophage-like cell lines. The LPS molecules, from Escherichia coli O111.B4, J5 and the lipid-A, were spin labelled with 2,2,6,6-tetramethylpiperidine-N-oxyl (Tempo) free radical in their sugar residues, and examined by electron spin resonance spectroscopy. This is the first report of the synthesis of spin-labelled endotoxins. Measurement of the rotational correlation times (Tc) indicated that the saccharide residues do not bind to membrane surface structures and suggests that the binding of LPS to macrophages is mediated by the lipid acyl chains. Anti-sera to LPS from E. coli O111.B4 was effective in binding to the polysaccharide of the same LPS bound to the cell surface.
KW - Endotoxin
KW - Macrophage
KW - Saccharide
KW - Spin label
UR - http://www.scopus.com/inward/record.url?scp=0026651028&partnerID=8YFLogxK
U2 - 10.1016/0167-4889(92)90133-V
DO - 10.1016/0167-4889(92)90133-V
M3 - Article
C2 - 1616938
AN - SCOPUS:0026651028
SN - 0167-4889
VL - 1135
SP - 165
EP - 170
JO - BBA - Molecular Cell Research
JF - BBA - Molecular Cell Research
IS - 2
ER -