Description

Nori Mouse cTnI ELISA Kit Summary

Alternative names for cTnI: Cardiac troponin I, TNNI3, TNNC1

Standard Curve

Kit Components
1. Pre-coated 96-well Microplate
2. Biotinylated Detection Antibody
3. Streptavidin-HRP Conjugate
4. Lyophilized Standards
5. TMB One-Step Substrate
6. Stop Solution
7. 20 x PBS
8. Assay Buffer

Other Materials Required but not Provided:
1. Microplate Reader capable of measuring absorption at 450 nm
2. Log-log graph paper or computer and software for ELISA data analysis
3. Precision pipettes (1-1000 µl)
4. Multi-channel pipettes (300 µl)
5. Distilled or deionized water

Protocol Outline
1. Prepare all reagents, samples and standards as instructed in the datasheet.
2. Add 100 µl of Standard or samples to each well and incubate 1 h at RT.
3. Add 100 µl of Working Detection Antibody to each well and incubate 1 h at RT.
4. Add 100 µl of Working Streptavidin-HRP to each well and incubate 20 min at RT.
5. Add 100 µl of Substrate to each well and incubate 5-30 min at RT.
6. Add 50 µl of Stop Solution to each well and read at 450 nm immediately.

Background: 

Troponin is a complex of three regulatory proteins (troponin C, troponin I, and troponin T) that is integral to muscle contraction in skeletal muscle and cardiac muscle, but not smooth muscle. Cardiac Troponin I (cTnI) is a protein that in humans is encoded by the TNNI3 gene.^[1] It is a tissue-specific subtype of troponin I. It has been shown to interact with PKD2L1,^[2] Troponin C type 1^[3] and Polycystic kidney disease 2.^[4] An increased level of cTnI in the blood has been shown to be a biomarker of heart disorders, the most important of which is myocardial infarction (MI). Raised troponin levels indicate cardiac muscle cell death as the enzyme is released into the blood upon injury to the heart. It is measured in the blood to differentiate between unstable angina and MI (heart attack) in people with chest pain or acute coronary syndrome. A person who had had a MI would have an area of damaged heart muscle and so would have elevated cardiac troponin levels in the blood.^[5] This can also occur in people with coronary vasospasm, a type of MI involving severe constriction of the cardiac blood vessels. After a MI cTnI may remain high for up to 2 weeks.^[6] It is important to note that cTnI is a marker of all heart muscle damage, not just myocardial infarction, which is the most severe form of heart disorder. However, diagnostic criteria for raised troponin indicating MI is currently set by the WHO at a threshold of 2 ug or higher. CTnI is also increased in patients with heart failure, where it also predicts mortality and ventricular rhythm abnormalities. They can rise in inflammatory conditions such as myocarditis and pericarditis with heart muscle involvement (myopericarditis). cTnI can also indicate several forms of cardiomyopathy. In a community-based cohort study indicating the importance of silent cardiac damage, troponin I has been shown to predict mortality and first coronary heart disease event in men free from cardiovascular disease at baseline.^[7]

References

1. Kimura A, et al. (1997). Nat Genet 16 (4): 379–82.
2. Li Q, et al. (2003). Biochemistry (United States) 42 (24): 7618–25.
3. Ward, DG, et al. (2004). Biochemistry (United States) 43 (13): 4020–7.
4. Li, Qiang; et al. (2003). Biochemistry (United States) 42 (2): 450–7.
5. Antman EM, et al. (1996). Engl. J. Med. 335 (18): 1342–9.
6. Amsterdam, E. A.; et al. (2014). Circulation 130: e344–e426.
7. Zethelius B, et al. (2006). Circulation 113 (8): 1071–8.

Product Citations