Differential endocytosis of fluorescein iso-thiocyanate-concanavalin A by normal and chronic myeloid leukemic granulocytes.
Isolated granulocytes from normal individuals and patients suffering from chronic myeloid leukemia (CML) displayed different fluorescent patterns on treatment with fluorescein isothiocyanate concanavalin A (Fl-Con A). The ligand was internalized by 86% of the normal granulocytes, while 80% of the leukemic granulocytes exhibited Fl-Con A localized on the cell periphery. In further experiments, pretreatment of the normal granulocytes with cytochalasin B, iodoacetamide, 2-deoxyglucose and sodium fluoride (but not with sodium azide or dinitrophenol) was found to drastically inhibit internalization of the ligand. However, pretreatment of granulocytes from CML patients with cytochalasin B and 2-deoxyglucose, caused only a little alteration in the pattern of Fl-Con A labelling relative to untreated cells. These results indicate that CML granulocytes are defective in their ability to endocytose Fl-Con A. We suggest that this differential interaction between Fl-Con A and normal and leukemic granulocytes is a convenient system to study the initial steps in receptor mediated endocytosis of Concanavalin A.
D001386:Azides / Q000494:pharmacology; D002454:Cell Differentiation; D002462:Cell Membrane / Q000378:metabolism; D003078:Colchicine / Q000494:pharmacology; D003208:Concanavalin A / Q000031:analogs & derivatives* / Q000378:metabolism; D003571:Cytochalasin B / Q000494:pharmacology; D004705:Endocytosis / Q000187:drug effects; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives*; D005452:Fluoresceins / Q000378:metabolism*; D006098:Granulocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D006651:Histocytochemistry; D006801:Humans; D007460:Iodoacetamide / Q000494:pharmacology; D007700:Kinetics; D007951:Leukemia, Myeloid / Q000097:blood / Q000378:metabolism / Q000503:physiopathology*; D019810:Sodium Azide; D012969:Sodium Fluoride / Q000494:pharmacology; D013997:Time Factors
D001386:Azides; D005452:Fluoresceins; C042784:fluorescein isothiocyanate-concanavalin A; D003208:Concanavalin A; D003571:Cytochalasin B; D012969:Sodium Fluoride; D019810:Sodium Azide; D016650:Fluorescein-5-isothiocyanate; D003078:Colchicine; D007460:Iodoacetamide