N-terminal telopeptide of type I collagen, which is also known as amino-terminal collagen crosslinks (NTX), is a telopeptide that can be measured as a biomarker to monitor the change rate of bone resorption. Creative BioMart Biomarker offers high quality detection service for NTX, ensuring high detection accuracy, sensitivity and efficiency for each sample.
NTX is a low molecular weight peptide containing hydroxylysylpyridinoline and lysylpyridinoline, in which lysylpyridinoline is mainly located in bone, accounting for 21% of mature collagen, and hydroxyethylpyridinium as the main component of mature collagen is located in cartilage and bone. NTX is the telopeptide of type I collagen crosslinks and the cross-linking agent of total N-terminal. Like CTX, NTX is also a degradation product of type I collagen. Both NTX and CTX are reliable biomarkers of bone resorption that have become the most commonly used markers for measuring bone resorption rate. Type I collagen is the main organic component of the extracellular matrix which has a triple helix structure. It is secreted as procollagen, followed by enzymatic hydrolysis to remove the N-propeptides and C-propeptides. Type I collagen is deposited in a form of quarter-stagger array which is joined together by pyridinium crosslinkers (deoxypyridinoline and pyridinoline). The main molecular site of type I collagen crosslinks is a short non-helical peptide at both terminals of the collagen molecule, which is called amino- (N-) and carboxyl- (C-) terminal peptides. During the osteoclast-guided bone resorption, cells attached to the bone form a closed area and secrete an acid that dissolves bone mineral. Osteoclasts release enzymes that are active at low pH (e.g. cathepsin K), they digest proteins and release fragments of type I collagen, where most fragments of NTX and CTX are small enough to be easily cleared by the kidneys. Therefore, they can be detected both in serum and urine. Studies have shown that NTX can accurately reflect the degree of myeloma disease and predict the early progression of bone disease after standard chemotherapy. In addition, in the diagnosis of Paget’s disease, NTX was more sensitive than biomarkers such as OHP, ICTP, PICP, OCN, etc. Because NTX can effectively reflect changes in bone resorption, it may be used as a diagnostic indicator and a prognostic indicator for bone disease.
Figure 1. Both NTX and CTX are reliable markers of bone resorption (Unnanuntana, et al. 2010)
Creative BioMart Biomarker strictly controls each specific experimental step in the NTX detection procedure to ensure accurately quantify the level of NTX in each sample.
At Creative BioMart Biomarker, we offer NTX detection service that includes several technical methods, you can communicate with our experts according to your research needs, and we will determine the final detection technological scheme based on the communication results. Please feel free to contact us, Creative BioMart Biomarker is here to offer you professional and thoughtful service.