This Article Full Text (PDF) Submit a related Letter to the Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by JAN, T. Articles by BAUMANN, G. Search for Related Content PubMed PubMed Citation Articles by JAN, T. Articles by BAUMANN, G.

Effects of Growth Hormone-Binding Proteins on Serum Growth Hormone Measurements^*

Center for Endocrinology, Metabolism, and Nutrition, Department of Medicine, Northwestern University Medical School Chicago, Illinois 60611

Address all correspondence and requests for reprints to: G. Baumann, M.D., 303 East Chicago Avenue, Chicago, Illinois 60611.

GH-binding proteins (GH-BPs) in human blood theoretically may interfere with measurements of immunoreactive GH by forming complexes with GH and competing with antibody reagents for ligand. Indeed, results of serum GH obtained by immunoassays are known to differ markedly depending on the assay employed. To assess the potential role of circulating GH-BPs in this phenomenon, we systematically examined their effect on GH measurement in four RIAs and two immunoradiometric assays. In all except one RIA, the effect of the BPs on tracer binding to antibody was mildly inhibitory. In both immunoradiometric assays, BPs increased the nonspecific association of the tracer with the solid phase reagent. However, these effects were minor at the BP concentrations realistically encountered in practice. Furthermore, the impact of BPs on GH standard curves and final results was negligible because BP effects fall into the category of nonspecific or zero dose counts, which are subtracted during data reduction. We conclude that GH-BPs are only a minor disturbance in GH immunoassays, which is completely compensated for by conventional assay design. Disparities among results yielded by different assays are probably not due to BP interference.

^* This work was presented in part at the 72nd Annual Meeting The Endocrine Society, Atlanta, GA, June 1990, and reported abstract form (Abstract 898). It was supported by NIH Grants DK-38128 and RR-05370 and a grant from the Northwestern Memorial Foundation.

Received July 25, 1990.

This article has been cited by other articles:

				B. C. Nindl, W. C. Hymer, D. R. Deaver, and W. J. Kraemer Growth hormone pulsatility profile characteristics following acute heavy resistance exercise J Appl Physiol, July 1, 2001; 91(1): 163 - 172. [Abstract] [Full Text] [PDF]

				M. Andersen, P. H. Petersen, O. Blaabjerg, J. Hangaard, and C. Hagen Evaluation of growth hormone assays using ratio plots Clin. Chem., May 1, 1998; 44(5): 1032 - 1038. [Abstract] [Full Text] [PDF]

				M. Tzanela, C. Wagner, and G. Shaffer Tannenbaum Recombinant Human Growth Hormone-Binding Protein Fails to Enhance the in Vivo Bioactivity of Human Growth Hormone in Normal Rats Endocrinology, December 1, 1997; 138(12): 5316 - 5324. [Abstract] [Full Text] [PDF]

				C. Jansson, C. Boguszewski, S. Rosberg, L. Carlsson, and K. Albertsson-Wikland Growth hormone (GH) assays: influence of standard preparations, GH isoforms, assay characteristics, and GH-binding protein Clin. Chem., June 1, 1997; 43(6): 950 - 956. [Abstract] [Full Text] [PDF]

				J. L. Stock, M. R. Warth, B. T. Teh, J. A. Coderre, J. H. Overdorf, G. Baumann, R. L. Hintz, M. L. Hartman, B. R. Seizinger, C. Larsson, et al. A Kindred with a Variant of Multiple Endocrine Neoplasia Type 1 Demonstrating Frequent Expression of Pituitary Tumors but Not Linked to the Multiple Endocrine Neoplasia Type 1 Locus at Chromosome Region 11q13 J. Clin. Endocrinol. Metab., February 1, 1997; 82(2): 486 - 492. [Abstract] [Full Text] [PDF]