Histidine-rich glycoprotein and concanavalin A synergistically stimulate the phosphatidylinositol 3-kinase-independent signaling pathway in leukocytes leading to increased cell adhesion and changes in cell morphology.
Histidine-rich glycoprotein (HRG) promoted the adhesion and morphological changes of human T-cell line MOLT-4 in a Con A-dependent manner. This morphological change-promoting activity was specific for HRG and the Arg23-Lys66 glycopeptide from human HRG. The carbohydrate chain at Asn45 was essential for this activity. The morphological changes of MOLT-4 cells caused by HRG and Con A (HRG/Con A) were not inhibited by phosphatidylinositol 3-kinase inhibitor, wortmannin or LY294002, while the changes by Con A alone were completely inhibited by these reagents, suggesting that HRG/Con A cooperate to activate leukocytes via a signaling pathway distinct from that by Con A alone. The morphological changes by Con A were associated with pseudopodia like structure. On the other hand, the morphological changes caused by HRG/Con A were associated not only with pseudopodia like structure but also with an increase of the F-actin-rich surface protrusions. Wortmannin inhibited only the formation of pseudopodia like structure.
Ohta
Takeshi
T
Department of Life Science, Graduate School of Life Science, University of Hyogo, Harima Science Garden City, Hyogo, Japan.
Ikemoto
Yoshitaka
Y
Saeki
Koichi
K
Koide
Takehiko
T
Wakabayashi
Sadao
S
D000730:Androstadienes / Q000494:pharmacology; D000925:Anticoagulants / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects / Q000276:immunology; D002867:Chromones / Q000494:pharmacology; D003208:Concanavalin A / Q000378:metabolism* / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006493:Heparin / Q000494:pharmacology; D006801:Humans; D007962:Leukocytes / Q000187:drug effects / Q000276:immunology*; D008934:Mitogens / Q000494:pharmacology; D009025:Morpholines / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D000081082:Phosphoinositide-3 Kinase Inhibitors; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011506:Proteins / Q000378:metabolism* / Q000494:pharmacology; D011554:Pseudopodia / Q000187:drug effects / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects; D000077191:Wortmannin; D000099053:Histidine-Rich Glycoprotein
D000730:Androstadienes; D000925:Anticoagulants; D002867:Chromones; D003208:Concanavalin A; D004791:Enzyme Inhibitors; D006493:Heparin; D008934:Mitogens; D009025:Morpholines; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D047428:Protein Kinase Inhibitors; D011506:Proteins; D000077191:Wortmannin; D000099053:Histidine-Rich Glycoprotein; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one