Regulation of neutrophil adhesion by pituitary growth hormone accompanies tyrosine phosphorylation of Jak2, p125FAK, and paxillin.

Neutrophil adhesion is fundamentally important during the onset of inflammatory responses. The adhesion signaling pathways control neutrophil arrest and extravasation and influence neutrophil shape and function at sites of inflammation. In the present study the intracellular signaling pathways for the adhesion of human neutrophils by pituitary growth hormone (GH) were ...
examined. Pituitary GH triggered the tyrosine phosphorylation of Janus kinase 2 (Jak2) and STAT3 in neutrophils. In addition, pituitary GH treatment resulted in the morphological changes and the tyrosine phosphorylation of focal adhesion kinase (p125FAK) and paxillin. Preincubation with genistein, a tyrosine kinase inhibitor, blocked the GH-stimulated adhesion and Jak2, STAT3, p125FAK, and paxillin phosphorylation. Confocal microscopy revealed that pituitary GH stimulates the focal localization of p125FAK, paxillin, phosphotyrosine, and filamentous actin filament into the membrane rufflings and uropods of human neutrophils. Immunoprecipitation experiments revealed a physical association of Jak2 with p125FAK via STAT3 in vivo. Also an in vitro kinase assay showed an augmentation of p125FAK autophosphorylation as a result of pituitary GH treatment. These results suggest that pituitary GH modulates neutrophil adhesion through tyrosine phosphorylation of Jak2, p125FAK, and paxillin and actin polymerization.
Mesh Terms:
Actins, Adult, Cell Adhesion, Cytoskeletal Proteins, DNA-Binding Proteins, Focal Adhesion Kinase 1, Focal Adhesion Protein-Tyrosine Kinases, Human Growth Hormone, Humans, Janus Kinase 2, Neutrophils, Paxillin, Phosphoproteins, Phosphorylation, Phosphotyrosine, Protein-Tyrosine Kinases, Proto-Oncogene Proteins, STAT3 Transcription Factor, Signal Transduction, Trans-Activators, Tyrosine
J. Immunol.
Date: Aug. 15, 2000
Download Curated Data For This Publication
180
Switch View:
  • Interactions 2