Clinical Chemistry Link to Randox Laboratories Web Site
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Clinical Chemistry 45: 18-20, 1999;
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Submit an electronic Letter to
the Editor about this paper
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via ISI Web of Science (72)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Apple, F. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Apple, F. S.
Related Collections
Right arrow Clinical Immunology
Right arrow Drug Monitoring and Toxicology
(Clinical Chemistry. 1999;45:18-20.)
© 1999 American Association for Clinical Chemistry, Inc.

Opinion

Clinical and Analytical Standardization Issues Confronting Cardiac Troponin I

Fred S. Applea

Department of Laboratory Medicine, and Pathology, Hennepin County Medical Center and, University of Minnesota, School of Medicine, Minneapolis, MN
a Address for correspondence. Hennepin County Medical Center, Clinical Laboratories, MC 812, 701 Park Avenue, Minneapolis, MN 55415. Fax 612-904-4229; e-mail fred.apple@co.hennepin.mn.us.


   Introduction
 
Troponin I, a subunit of the ternary troponin complex, is a regulatory protein of the thin filament of striated muscle. Cardiac troponin I (cTnI) is uniquely different from the troponin I found in either slow or fast skeletal muscle. Possessing an additional 31-amino acid sequence at its N terminus, cTnI is found exclusively in the myocardium and, therefore, has been extensively studied as a sensitive and specific serum marker for myocardial injury (1). The forms of cTnI found in the circulation include complexes with troponin T and C (TIC and IC) as well as free subunits (2). In addition, cTnI has been identified in oxidized, reduced, and phosphorylated forms (3)(4). The signals generated by immunoassays developed with anti-cTnI monoclonal antibodies are dependent on the epitope region recognized by these antibodies (5). Thus, protein regions within the cTnI molecule that are susceptible to oxidation, reduction, or phosphorylation or to degradation by the action of proteases are likely to exhibit variable immunoreactivity and even loss of reactivity, leading to altered signal generation in cTnI immunoassays that use antibodies against such regions.

In the December 1998 issue of Clinical Chemistry, Katrukha et al. (6) presented Western blotting and immunoassay data demonstrating the in vivo and in vitro degradation of both the C and N termini of cTnI in human myocardium and serum after acute myocardial infarction (AMI). More importantly, they demonstrated that the signal detected by cTnI immunoassays is highly dependent on the epitope regions recognized by the anti-cTnI antibodies used in the (sandwich) immunoassays. Thus, whether cTnI is complexed with troponin T and or with troponin C as the three-subunit complex TIC or the two-subunit complex IC or as a free subunit, immunoassays designed with antibodies selected against the . . . [Full Text of this Article]


   Acknowledgments
 

   References
 



The following articles in journals at HighWire Press have cited this article:


Home page
 Asian Cardiovasc. Thorac. Ann.Home page
D. Abramov, M. Abu-Tailakh, M. Frieger, A. Ganiel, D. Tuvbin, and A. Wolak
Plasma Troponin Levels After Cardiac Surgery vs After Myocardial Infarction
Asian Cardiovasc Thorac Ann, December 1, 2006; 14(6): 530 - 535.
[Abstract] [Full Text] [PDF]

Home page
 J Am Coll CardiolHome page
A. S. Jaffe, L. Babuin, and F. S. Apple
Biomarkers in Acute Cardiac Disease: The Present and the Future
J. Am. Coll. Cardiol., July 4, 2006; 48(1): 1 - 11.
[Abstract] [Full Text] [PDF]

Home page
 CMAJHome page
L. Babuin and A. S. Jaffe
Troponin: the biomarker of choice for the detection of cardiac injury
Can. Med. Assoc. J., November 8, 2005; 173(10): 1191 - 1202.
[Abstract] [Full Text] [PDF]

Home page
 Clin. Chem.Home page
S. Eriksson, H. Halenius, K. Pulkki, J. Hellman, and K. Pettersson
Negative Interference in Cardiac Troponin I Immunoassays by Circulating Troponin Autoantibodies
Clin. Chem., May 1, 2005; 51(5): 839 - 847.
[Abstract] [Full Text] [PDF]

Home page
 Eur Heart JHome page
M. Panteghini
Role and importance of biochemical markers in clinical cardiology
Eur. Heart J., July 2, 2004; 25(14): 1187 - 1196.
[Abstract] [Full Text] [PDF]

Home page
 Br J AnaesthHome page
M. Kemp, J. Donovan, H. Higham, and J. Hooper
Biochemical markers of myocardial injury
Br. J. Anaesth., July 1, 2004; 93(1): 63 - 73.
[Abstract] [Full Text] [PDF]

Home page
 HeartHome page
K A A Fox, J Birkhead, R Wilcox, C Knight, and J Barth
British Cardiac Society Working Group on the definition of myocardial infarction
Heart, June 1, 2004; 90(6): 603 - 609.
[Abstract] [Full Text] [PDF]

Home page
 Clin. Chem.Home page
S. Eriksson, M. Junikka, P. Laitinen, K. Majamaa-Voltti, H. Alfthan, and K. Pettersson
Negative Interference in Cardiac Troponin I Immunoassays from a Frequently Occurring Serum and Plasma Component
Clin. Chem., July 1, 2003; 49(7): 1095 - 1104.
[Abstract] [Full Text] [PDF]

Home page
 ChestHome page
M. Panteghini
Acute Coronary Syndrome: Biochemical Strategies in the Troponin Era
Chest, October 1, 2002; 122(4): 1428 - 1435.
[Abstract] [Full Text] [PDF]

Home page
 Annals of Clinical & Laboratory ScienceHome page
T. M. Welsh, G. D. Kukes, and L. M. Sandweiss
Differences of Creatine Kinase MB and Cardiac Troponin I Concentrations in Normal and Diseased Human Myocardium
Ann. Clin. Lab. Sci., January 1, 2002; 32(1): 44 - 49.
[Abstract] [Full Text] [PDF]

Home page
 Clin. Chem.Home page
A. Lavoinne, B. Cauliez, H. Eltchaninoff, R. Koning, and A. Cribier
Analytical and Clinical Performance of the Immulite Cardiac Troponin I Assay
Clin. Chem., December 1, 2000; 46(12): 1989 - 1990.
[Full Text] [PDF]

Home page
 J Am Coll CardiolHome page
D. A. Morrow, E. M. Antman, M. Tanasijevic, N. Rifai, J. A. de Lemos, C. H. McCabe, C. P. Cannon, and E. Braunwald
Cardiac troponin I for stratification of early outcomes and the efficacy of enoxaparin in unstable angina: a TIMI-11B substudy
J. Am. Coll. Cardiol., November 15, 2000; 36(6): 1812 - 1817.
[Abstract] [Full Text] [PDF]

Home page
 Clin. Chem.Home page
F. S. Apple, F. P. Anderson, P. Collinson, R. L. Jesse, M. C. Kontos, M. A. Levitt, E. A. Miller, and M. M. Murakami
Clinical Evaluation of the First Medical Whole Blood, Point-of-Care Testing Device for Detection of Myocardial Infarction
Clin. Chem., October 1, 2000; 46(10): 1604 - 1609.
[Abstract] [Full Text] [PDF]

Home page
 CirculationHome page
A. S. Jaffe, J. Ravkilde, R. Roberts, U. Naslund, F. S. Apple, M. Galvani, and H. Katus
It's Time for a Change to a Troponin Standard
Circulation, September 12, 2000; 102(11): 1216 - 1220.
[Full Text] [PDF]

Home page
 CirculationHome page
R. Labugger, L. Organ, C. Collier, D. Atar, and J. E. Van Eyk
Extensive Troponin I and T Modification Detected in Serum From Patients With Acute Myocardial Infarction
Circulation, September 12, 2000; 102(11): 1221 - 1226.
[Abstract] [Full Text] [PDF]

Home page
 Eur Heart JHome page
Myocardial
Myocardial infarction redefined--A consensus document of The Joint European Society of Cardiology/American College of Cardiology Committee for the Redefinition of Myocardial Infarction
Eur. Heart J., September 2, 2000; 21(18): 1502 - 1513.
[Abstract] [PDF]

Home page
 J Am Coll CardiolHome page
E. Braunwald, E. M. Antman, J. W. Beasley, R. M. Califf, M. D. Cheitlin, J. S. Hochman, R. H. Jones, D. Kereiakes, J. Kupersmith, T. N. Levin, et al.
ACC/AHA guidelines for the management of patients with unstable angina and non-st-segment elevation myocardial infarction: A report of the american college of cardiology/ american heart association task force on practice guidelines (committee on the management of patients with unstable angina)
J. Am. Coll. Cardiol., September 1, 2000; 36(3): 970 - 1062.
[Full Text] [PDF]

Home page
 Clin. Chem.Home page
H. Stiegler, Y. Fischer, J. F. Vazquez-Jimenez, J. Graf, K. Filzmaier, B. Fausten, U. Janssens, A. M. Gressner, and D. Kunz
Lower Cardiac Troponin T and I Results in Heparin-Plasma Than in Serum
Clin. Chem., September 1, 2000; 46(9): 1338 - 1344.
[Abstract] [Full Text] [PDF]

Home page
 Clin. Chem.Home page
J. Ravkilde
Risk Stratification in Acute Coronary Syndrome Using Cardiac Troponin I
Clin. Chem., April 1, 2000; 46(4): 443 - 444.
[Full Text] [PDF]

Home page
 Clin. Chem.Home page
D. A. Morrow, N. Rifai, M. J. Tanasijevic, D. R. Wybenga, J. A. de Lemos, and E. M. Antman
Clinical Efficacy of Three Assays for Cardiac Troponin I for Risk Stratification in Acute Coronary Syndromes: A Thrombolysis In Myocardial Infarction (TIMI) 11B Substudy
Clin. Chem., April 1, 2000; 46(4): 453 - 460.
[Abstract] [Full Text] [PDF]

Home page
 Clin. Chem.Home page
P. Datta, K. Foster, and A. Dasgupta
Comparison of Immunoreactivity of Five Human Cardiac Troponin I Assays toward Free and Complexed Forms of the Antigen: Implications for Assay Discordance
Clin. Chem., December 1, 1999; 45(12): 2266 - 2269.
[Full Text] [PDF]

Home page
 Clin. Chem.Home page
D. H. Wilson, D. M. Laird, C. M. Forsythe, T. T. Biegalski, A. L. Keller, and R. J. Herrmann
Antibody Selection for the Abbott AxSYM Troponin I Assay
Clin. Chem., December 1, 1999; 45(12): 2293 - 2294.
[Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1999 by the American Association for Clinical Chemistry.