Epidermal growth factor

EPIDERMAL GROWTH FACTOR (EGF)

  • It was first isolated from the salivary gland extracts of mice. It is found in significant amount in the submaxillary gland of male mice. Injection of saliva of male mice into new born mice results in
    • Precocious opening of eyelids as early as seven days; instead 12-14 days.
    • Precocious eruption of teeth (incisors) at 6-7 days instead of 10 days.
  • EGF acts directly on the epidermis rather than through secondary control mechanisms. It stimulates epidermal cell proliferation and keratirdzation
  • EGF was discovered by Cohen and subsequently his group expanded our understanding of EGF and its receptor EGFR.9 EGFR is a 170 kDa membrane glycoprotein which is activated by multiple ligands including EGF, transforming growth factor (TGF)-a, heparin binding (HB)-EGF, amphiregulin, b-cellulin and epiregulin, all of which are synthesised as transmembrane precursors (proligands) that are inserted in the cell surface and cleaved by proteases to release the mature soluble growth factor. The EGFR signalling pathway has been known to be involved in a variety of physiological responses including proliferation, differentiation, motility, and survival.
  • EGF (Epidermal growth factor) is found in varying concentrations in milk, saliva, urine, plasma and also in most other body fluids. Cells in various organs, including brain, kidney, salivary gland, and stomach, produce this factor. EGF is a globular protein of 6.4 kDa consisting of 53 amino acids. It contains three intramolecular disulfide bonds essential for biological activity. EGF controls and stimulates the proliferation of epidermal and epithelial cells, including fibroblasts, kidney epithelial cells, human glial cells, ovary granulosa cells, and thyroid cells in vitro. The proliferation of some cell lines have been shown to be inhibited by EGF. EGF is a strong chemoattractant for fibroblasts and epithelial cells. EGF alone and also in combination with other cytokines is an important factor mediating wound.
Last modified: Monday, 9 January 2012, 6:30 AM