Interleukin 7 receptor engagement stimulates tyrosine phosphorylation, inositol phospholipid turnover, proliferation, and selective differentiation to the CD4 lineage by human fetal thymocytes.

• DOI: 10.1073/pnas.88.14.6323
• Publication Date: 2006-05-31T11:41:42Z
• Authors: F M Uckun; L Tuel-Ahlgren; V Obuz; R Smith; I Dibirdik; M Hanson; M C Langlie; J A Ledbetter
• Keywords: Receptors, Interleukin-7; Interleukin-7; Interleukins; T-Lymphocytes; Antibodies, Monoclonal; Cell Differentiation; Inositol 1,4,5-Trisphosphate; Thymus Gland; Protein-Tyrosine Kinases; Lymphocyte Activation; Phosphatidylinositols; Recombinant Proteins; Enzyme Activation; Fetus; Antigens, CD; CD4 Antigens; Cytokines; Humans; Phosphorylation; Receptors, Immunologic

The purposes of this study were to elucidate the effects recombinant human interleukin 7 (rhIL-7) on proliferation as well differentiation fetal thymocytes and analyze biochemical nature IL-7 receptor-linked transmembrane signal. In absence costimulants, rhIL-7 stimulated in vitro colony formation CD4+CD8+ double-positive immature thymocytes. Furthermore, promoted partial with a selective advantage for development CD4+CD8- single-positive Our observations suggest that likely has an important regulatory role during earliest stages T-cell ontogeny. Stimulation resulted enhanced tyrosine phosphorylation three distinct phosphoproteins molecular masses 72, 98, 123, 190 kDa induced rapid biphasic increase production inositol 1,4,5-trisphosphate, which was inhibitable by protein kinase inhibitor genistein. Thus, signal triggered engagement receptor is intimately linked functional pathway stimulates phospholipid turnover proliferation, CD4 lineage,