Activation and inhibition of anaplastic lymphoma kinase receptor tyrosine kinase by monoclonal antibodies and absence of agonist activity of pleiotrophin.
Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase that is transiently expressed in specific regions of the central and peripheral nervous systems, suggesting a role in its normal development and function. The nature of the cognate ligands of ALK in vertebrate is still a matter of debate. We produced a panel of monoclonal antibodies (mAbs) directed against the extracellular domain of the human receptor. Two major species of ALK (220 and 140 kDa) were identified in transfected cells, and the use of our mAbs established that the 140-kDa species results from a cleavage of the 220-kDa form. Two mAbs, in the nm range, induced the differentiation of PC12 cells transiently transfected with ALK. In human embryonic kidney 293 cells stably expressing ALK, these two mAbs strongly activated the receptor and subsequently the mitogen-activated protein kinase pathway. We further showed for the first time that activation of ALK also resulted in a specific activation of STAT3. In contrast, other mAbs presented the characteristics of blocking antibodies. Finally, in these cell systems, a mitogenic form of pleiotrophin, a proposed ligand of ALK, failed to activate this receptor. Thus, in the absence of clearly established ligand(s) in vertebrates, the availability of mAbs allowing the activation or the inhibition of the receptor will be essential for a better understanding of the biological roles of ALK.
Moog-Lutz
Christel
C
INSERM, Unité 706/Université Pierre et Marie Curie, Paris F-75005, France.
Degoutin
Joffrey
J
Gouzi
Jean Y
JY
Frobert
Yvelyne
Y
Brunet-de Carvalho
Nicole
N
Bureau
Jocelyne
J
Créminon
Christophe
C
Vigny
Marc
M
D000077548:Anaplastic Lymphoma Kinase; D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry*; D002352:Carrier Proteins / Q000737:chemistry / Q000494:pharmacology*; D002460:Cell Line; D016207:Cytokines / Q000737:chemistry / Q000494:pharmacology*; D018076:DNA, Complementary / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006801:Humans; D008024:Ligands; D020935:MAP Kinase Signaling System; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D008954:Models, Biological; D009474:Neurons / Q000378:metabolism; D016716:PC12 Cells; D010766:Phosphorylation; D010957:Plasmids / Q000378:metabolism; D017434:Protein Structure, Tertiary; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D051381:Rats; D020794:Receptor Protein-Tyrosine Kinases; D013997:Time Factors; D014162:Transfection; D014443:Tyrosine / Q000737:chemistry
D000911:Antibodies, Monoclonal; D002352:Carrier Proteins; D016207:Cytokines; D018076:DNA, Complementary; D004791:Enzyme Inhibitors; D008024:Ligands; C066845:pleiotrophin; D014443:Tyrosine; C000626173:ALK protein, human; C000626175:Alk protein, rat; D000077548:Anaplastic Lymphoma Kinase; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3