Related Experiment Video
Updated: Oct 16, 2025

Quantitative Determination of De Novo Fatty Acid Synthesis in Brown Adipose Tissue Using Deuterium Oxide
Published on: May 12, 2023
Determination of 97.5th and 99th percentile upper reference limits for heart-type fatty acid-binding protein (H-FABP)
Michael A Vera1, Christopher D Koch1, Peter A Kavsak2
1Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT, USA.
Background:
Heart-type fatty acid binding protein (H-FABP), a low molecular weight protein found primarily in myocardial tissue, has been identified as a potential biomarker in the detection of acute coronary syndrome and acute kidney injury. To further investigate clinical utility, we sought to establish an upper reference limit (URL) of H-FABP within a healthy U.S.
Methods:
Serum samples of healthy donors were acquired from the AACC Universal Sample Bank. We analyzed 355 samples for H-FABP concentration using the Randox Laboratories immunoturbidimetric assay on the Roche Cobas 8000 series analyzer.
Results:
The final sample population consisted of individuals aged 18-74 y, with 170 males and 185 females. The distribution of the population exhibited a strong positive skew, affecting outlier analysis and URL determination. The 97.5th-percentile URL was found to be 7.4 ng/ml (95% CI: 6.3-9.2), while the 99th-percentile URL was 12.1 ng/ml (8.6-14.9).
Conclusion:
As the URL for H-FABP is highly affected by population distribution and outlier removal, final determination for an assay cutoff should be made in the context of clinical utility, either as a standalone assay or in conjunction with other biomarkers, and the desired clinical sensitivity and specificity.
Related Concept Videos
Blood Studies for Cardiovascular System II: CRP, Hcy, and Cardiac Natriuretic Peptide Markers
These markers indicate stress or strain on the heart muscle:
Natriuretic Peptides (BNP)
Cardiac myocytes produce these hormones in response to ventricular stretching...
Blood Studies for Cardiovascular System III: Serum Lipid Profile
Serum lipids are fats and fatty substances in the blood and are crucial for various bodily functions, including energy storage, cellular structure, and hormone production. Serum lipids consist of cholesterol, triglycerides, and phospholipids.
Cholesterol is a soft, fat-like substance found in all body cells. It is crucial for producing hormones, vitamin D, and substances that aid...

