Critical role of Lyn kinase in inhibition of neutrophil apoptosis by granulocyte-macrophage colony-stimulating factor.
The signal pathway for control of apoptosis in human neutrophils is currently unknown. In this study, we provide the first evidence that a Src family tyrosine kinase, Lyn, plays a key role in inhibition polymorphonuclear (PMN) cell death. Several nuclear proteins associated with apoptosis, i.e., p53, cdc2, and Rb, were absent from PMN. Bcl-2, known to inhibit apoptosis, was also not expressed. Programmed cell death that rapidly occurred in PMN could be arrested by granulocyte-macrophage CSF (GM-CSF), but this activation did not induce p53, cdc2, retinoblastoma, or Bcl-2 expression. Instead, GM-CSF produced a rapid activation of Lyn and Hck, but not Fgr, tyrosine phosphorylation within 1 min. Co-immunoprecipitation studies indicated that only Lyn, but not Hck, was physically coupled to GM-CSF receptor. By histologic assessment and evaluation of DNA fragmentation, only antisense Lyn, but not antisense Hck or antisense Fgr, could reverse the cell survival advantage provided by GM-CSF. Therefore, the physical coupling of Lyn to GM-CSF receptor and its early activation are required for inhibition or delay of apoptosis in PMN.
Wei
S
S
Immunology Program, H. Lee Moffitt Cancer Center & Research Institute, University of South Florida College of Medicine, Tampa 33612, USA.
Liu
J H
JH
Epling-Burnette
P K
PK
Gamero
A M
AM
Ussery
D
D
Pearson
E W
EW
Elkabani
M E
ME
Diaz
J I
JI
Djeu
J Y
JY
D017209:Apoptosis / Q000187:drug effects* / Q000502:physiology*; D001483:Base Sequence; D004789:Enzyme Activation; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology*; D016376:Oligonucleotides, Antisense / Q000235:genetics; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D051572:Proto-Oncogene Proteins c-hck; D011994:Recombinant Proteins; D015398:Signal Transduction / Q000502:physiology; D019061:src-Family Kinases / Q000235:genetics / Q000502:physiology*
D016376:Oligonucleotides, Antisense; D011518:Proto-Oncogene Proteins; D011994:Recombinant Proteins; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D011505:Protein-Tyrosine Kinases; C496631:HCK protein, human; D051572:Proto-Oncogene Proteins c-hck; C060902:lyn protein-tyrosine kinase; D019061:src-Family Kinases