Faculty Collaboration Database

Tyrosine kinase activity of the EGF receptor in murine metanephric organ culture. Kidney Int 1995 Mar;47(3):774-81

Date

03/01/1995

Pubmed ID

7752576

DOI

10.1038/ki.1995.118

Scopus ID

2-s2.0-0028936982 (requires institutional sign-in at Scopus site)   53 Citations

Abstract

Epidermal growth factor (EGF) and its fetal form, transforming growth factor alpha (TGF-alpha) are renal mitogens which induce epithelial hyperplasia, proximal tubular cyst formation (TC), and accelerated distal nephron differentiation in metanephric organ culture. To delineate the intracellular mechanisms mediating these growth factor effects, we studied the specific role of the epidermal growth factor receptor (EGF-R), the common receptor for both ligands, as an activated tyrosine kinase in TC formation and nephrogenesis. Fetal murine metanephric explants were incubated for 120 hours in control, and EGF (15 ng/ml)/TGF-alpha (10 ng/ml) supplemented medium with and without EGF-R blocking monoclonal antibody (50 mg/ml), or tyrosine kinase inhibitor. EGF-R tyrosine kinase inhibition was achieved by incubation with a synthetic tyrphostin (TP B42) (0.1 microM) or genestein (5.5 micrograms/ml). The following parameters were assessed: (a) segment-specific nephron development using morphometry and immunohistology; (b) tubular epithelial hyperplasia by protein content and BrdU uptake; and (c) TC formation by morphometric cystic index. Both growth factors produced hyperplastic proximal TC, significantly increased explant growth, and significantly increased distal nephron differentiation. Inhibiting the ligand-EGF-R interaction with EGF-R blocking monoclonal antibody abolished all growth factor-induced effects and resulted in increased amounts of undifferentiated mesenchyme and decreased distal nephron differentiation. Inhibition of EGF-R tyrosine kinase activity with either Tyrphostin B42 or genestein blocked TC formation and produced nodular blastemal hyperplasia and decreased distal nephron differentiation.

Author List

Pugh JL, Sweeney WE Jr, Avner ED

Author

Ellis D. Avner MD Professor in the Pediatrics department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Antibodies, Monoclonal
Catechols
Cell Division
Epidermal Growth Factor
ErbB Receptors
Genistein
Immunohistochemistry
Isoflavones
Kidney
Mice
Nitriles
Organ Culture Techniques
Transforming Growth Factor alpha
Tyrphostins