08/21/2013

Epitope Diagnostics, Inc.

First Immunoassay Kit that Exclusively Measures Human Intact FGF-21

San Diego, CA, May 31, 2013 --(PR.com)-- Epitope Diagnostics is pleased to introduce an innovative ELISA kit for the simple, accurate measurement of human intact FGF-21. The test is useful as an aid in diagnosis of primary muscle-manifesting respiratory chain deficiencies, nonalcoholic fatty liver disease and other conditions related to type 2 diabetes, gestational diabetes and obesity.


Fibroblast Growth Factor 21 (FGF-21) belongs to the FGF-19 subfamily, which includes FGF-19, FGF-21 and FGF-23. The FGF-19 family members are potent endocrine hormones in the regulation of a diverse physiological homeostasis. The intact FGF-21 is a small protein comprising 181 amino acids. Administration of recombinant FGF-21 lowered plasma glucose and insulin levels, reduced hepatic and circulating triglycerides and cholesterol levels, and improved insulin sensitivity, energy expenditure, hepatic steatosis and obesity in a range of insulin-resistant animal models. The physiological functions of FGF-21 are relied on the intact molecular structure and amino acid sequence in its N-terminal and C-terminal region. An N-terminal truncated FGF-21 (7-181) is a potent inhibitor that competitively inhibits the biological activity of intact FGF-21 (1-181). Therefore, it is important to measure the circulation intact FGF-21 level in the assessment of the physiological and pathophysiological condition. An assay that determines the fragment of the FGF-21 might overestimate the biological activity of the protein in test sample. Circulation FGF-21 is a biomarker and its levels are increased in patients with nonalcoholic fatty liver disease (NAFLD), type 2 diabetes, gestational diabetes and obesity. An increase of circulating FGF-21 is also found in patients with Cushing’s syndrome, patients with lipodystrophy induced by HIV-1 and patients with chronic renal disease or end-stage renal disease (ESRD).


Current commercial FGF-21 assays don’t different well between normal subjects and patients with diabetes and obesity. Similarly, these assays show extremely high normal cut-off, ~ 800 pg/ml - 1100 pg/ml. Marking a turning point in FGF21 ELISA technology, the Epitope ELISA answers the need for a reproducible, high performing assay to measure human intact FGF21.


The EDI Human Intact FGF-21 ELISA kit is the first immunoassay kit that exclusively measures human intact FGF-21, a capability that has been lacking for commercial kits previously available. Additionally, this intact FGF-21 assay shows a much lower normal cut-off than other previous FGF-21 assays (usually 800 – 1100 pg/ml), which may lead to a better differentiation between normal subjects and patients with diabetes and obesity.


1. Yie J, et al. FGF21 N- and C-termini play different roles in receptor interaction and activation. FEBS Lett. 2009 Jan 5;583:19-24.
2. Micanovic R, et al. Different roles of N- and C- termini in the functional activity of FGF21. J Cell Physiol. 2009 May;219(2):227-34.
3. Yusuke Murata, et al. FGF21 as an Endocrine Regulator in Lipid Metabolism: From Molecular Evolution to Physiology and Pathophysiology. Journal of Nutrition and Metabolism, Vol 2011, Article ID 981315, 8 pages