TY - JOUR
T1 - Macrophage scavenger receptor marco
T2 - In vitro and in vivo regulation and involvement in the anti-bacterial host defense
AU - Van Der Laan, Luc J.W.
AU - Kangas, Maarit
AU - Döpp, Ed A.
AU - Broug-Holub, Ellen
AU - Elomaa, Outi
AU - Tryggvason, Karl
AU - Kraal, Georg
PY - 1997/6
Y1 - 1997/6
N2 - Recently, a novel murine member of the scavenger receptor class A family, designated MARCO, has been cloned [4]. Scavenger receptors have a characteristic broad ligand specificity and are able to bind various substances, including bacteria cell surface components. The receptor MARCO is expressed by a distinct subset of macrophages in spleen and lymph nodes. Using a panel of monoclonal antibodies (mAbs) specifically directed against MARCO, we investigated the regulation of this receptor in vitro and in vivo. Stimulation of the mouse macrophage cell line J774.2 in vitro with bacterial lipopolysaccharides (LPS) induces upregulation of MARCO surface expression. In accordance with this observation, in mice suffering from endotoxin shock caused by bacterial infection, expression of MARCO is induced on macrophages in the liver, lung and spleen, which normally do not express this receptor. We found that two of the anti-MARCO mAbs, ED29 and ED31, were able to block ligand binding. They inhibited the uptake of heat-killed Escherichia coli by MARCO expressing CHO cells. Further experiments will be needed to confirm the importance of MARCO in the anti-bacterial host defense.
AB - Recently, a novel murine member of the scavenger receptor class A family, designated MARCO, has been cloned [4]. Scavenger receptors have a characteristic broad ligand specificity and are able to bind various substances, including bacteria cell surface components. The receptor MARCO is expressed by a distinct subset of macrophages in spleen and lymph nodes. Using a panel of monoclonal antibodies (mAbs) specifically directed against MARCO, we investigated the regulation of this receptor in vitro and in vivo. Stimulation of the mouse macrophage cell line J774.2 in vitro with bacterial lipopolysaccharides (LPS) induces upregulation of MARCO surface expression. In accordance with this observation, in mice suffering from endotoxin shock caused by bacterial infection, expression of MARCO is induced on macrophages in the liver, lung and spleen, which normally do not express this receptor. We found that two of the anti-MARCO mAbs, ED29 and ED31, were able to block ligand binding. They inhibited the uptake of heat-killed Escherichia coli by MARCO expressing CHO cells. Further experiments will be needed to confirm the importance of MARCO in the anti-bacterial host defense.
UR - http://www.scopus.com/inward/record.url?scp=0030813871&partnerID=8YFLogxK
U2 - 10.1016/S0165-2478(97)00077-1
DO - 10.1016/S0165-2478(97)00077-1
M3 - Article
C2 - 9232452
AN - SCOPUS:0030813871
SN - 0165-2478
VL - 57
SP - 203
EP - 208
JO - Immunology Letters
JF - Immunology Letters
IS - 1-3
ER -