The two-site growth hormone binding protein (GHBP) ELISA is highly specific for the soluble, extracellular portion of the human GH receptor, and is calibrated using pure recombinant DNA-derived GHBP. This convenient ELISA allows the reliable measurement of circulating GHBP, and may be fully automated on open-platform microplate systems.
GHBP modulates GH action by a variety of mechanisms. It inhibits GH action by competing with the GH receptor for ligand and by generating “unproductive” heterodimers with the GH receptor at the cell surface, as opposed to the GH receptor homodimers required for signaling. The GHBP also prolongs the half-life of GH in the circulation by complexing GH and delaying its elimination. The main clinical application of GHBP measurements is the diagnosis of genetic growth hormone insensitivity (Laron syndrome), where levels are typically decreased.
Diagnostic Systems Laboratories, Inc.
www.CLPmag.com
Keywords: endocrinology
