PS-liposome and ox-LDL bind to different sites of the immunodominant domain (#155-183) of CD36: a study with GS95, a new anti-CD36 monoclonal antibody.
CD36, a multifunctional adhesive receptor on a variety of cells such as monocytes and platelets, has been implicated in clearance of modified LDL and in the removal of apoptotic or senescent cells. We recently developed a new anti-CD36 monoclonal antibody, GS95. We determined the binding site of phosphatidylserine (PS)-liposome on CD36 by flow cytometric analysis of competitive bindings between phospholipid-liposomes or synthetic CD36 peptides and FITC-labeled anti-CD36 antibodies (GS95, OKM5, and FA6-152). The epitope of GS95 was mapped to the amino acid sequence #162-183 of CD36 that was partially overlapped with, but distinct from, #155-183, which has been reported as the epitopes of two commercially available antibodies, OKM5 and FA6-152. Oxidized-LDL dose-dependently inhibited bindings of both GS95 and OKM5 antibodies to platelet CD36, while PS-liposome inhibited the binding of GS95 but not OKM5 or FA6-152. These results indicate that the binding site of PS-liposome on platelet CD36 is not identical to that of oxidized-LDL and may be located in the amino acid sequence #162-183.
Yamaguchi
A
A
Department of Cardiovascular Research, The Tokyo Metropolitan Institute of Medical Science, Tokyo Metropolitan Organization for Medical Research, Japan. a-yama@rinshoken.or.jp
Yamamoto
N
N
Akamatsu
N
N
Saido
T C
TC
Kaneda
M
M
Umeda
M
M
Tanoue
K
K
D000328:Adult; D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000302:isolation & purification / Q000378:metabolism; D001667:Binding, Competitive; D001792:Blood Platelets / Q000737:chemistry / Q000378:metabolism; D018955:CD36 Antigens / Q000276:immunology* / Q000378:metabolism*; D005434:Flow Cytometry; D006801:Humans; D016056:Immunodominant Epitopes / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D008077:Lipoproteins, LDL / Q000378:metabolism*; D008081:Liposomes / Q000737:chemistry; D008297:Male; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000138:chemical synthesis / Q000276:immunology / Q000494:pharmacology; D010084:Oxidation-Reduction; D010718:Phosphatidylserines / Q000378:metabolism* / Q000494:pharmacology; D013915:Thrombasthenia / Q000097:blood / Q000276:immunology
D000911:Antibodies, Monoclonal; D018955:CD36 Antigens; D016056:Immunodominant Epitopes; D008077:Lipoproteins, LDL; D008081:Liposomes; D009842:Oligopeptides; D010718:Phosphatidylserines; C099252:oxidized low density lipoprotein