Overview
Cystatin C is a small protein belonging to the cysteine protease inhibitor family. It is produced at a constant rate by all nucleated cells and is freely filtered by the glomeruli, making it an excellent biomarker for estimating glomerular filtration rate (GFR). Unlike creatinine, cystatin C is less influenced by muscle mass or diet, providing a more accurate assessment of kidney function. In clinical settings, cystatin C is increasingly used to detect early-stage kidney disease, particularly in populations where creatinine-based estimates may be unreliable, such as in children, the elderly, or patients with reduced muscle mass. Its role extends beyond nephrology, with emerging applications in cardiovascular and neurodegenerative disease research.
Physical and Chemical Properties
Cystatin C has a molecular weight of approximately 13.3 kilodaltons (kDa) and consists of 120 amino acids. It is characterized by its stability across a wide pH range and resistance to proteolytic degradation, which contributes to its reliability as a biomarker. The protein forms tight complexes with cysteine proteases, inhibiting their activity. In solution, cystatin C is highly soluble in water and common physiological buffers. It maintains structural integrity under typical storage conditions (2-8°C) but may degrade if exposed to repeated freeze-thaw cycles or extreme temperatures. Analytical methods for cystatin C detection typically employ immunoassays due to its high specificity and low cross-reactivity with other proteins.
Main Applications
The primary application of cystatin C is in the assessment of kidney function. It serves as a sensitive marker for glomerular filtration rate (GFR), with several advantages over traditional creatinine-based measurements. Clinically, it is used to diagnose and monitor chronic kidney disease (CKD), particularly in early stages where creatinine levels may still appear normal. Beyond nephrology, cystatin C has shown promise as a prognostic marker in cardiovascular diseases, where elevated levels correlate with increased risk of heart failure and mortality. Research applications include studies of Alzheimer's disease and other neurodegenerative conditions, as cystatin C may play a role in amyloid-beta regulation. The protein is also used in vitro as a cysteine protease inhibitor in biochemical research.
Safety and Storage
Cystatin C is generally considered safe for handling under standard laboratory conditions. As with all biological materials, appropriate personal protective equipment should be worn, including gloves and lab coats. Although not classified as hazardous, precautions should be taken to avoid inhalation of powder or direct contact with eyes and skin. For long-term storage, cystatin C should be kept at 2-8°C in its original container. Lyophilized preparations are stable for several years when stored properly, while reconstituted solutions should be used within a few days or according to manufacturer recommendations. Avoid repeated freeze-thaw cycles, as this may degrade the protein and affect assay performance. Proper documentation should be maintained for tracking storage conditions and expiration dates.
B2B Procurement Guide
When procuring cystatin C for clinical or research use, several factors should be considered. Purity is critical, with most applications requiring ≥95% purity as verified by SDS-PAGE or HPLC. For diagnostic applications, ensure the product meets clinical-grade standards and has low endotoxin levels (<1 EU/μg). Suppliers should provide comprehensive characterization data, including mass spectrometry analysis and functional activity testing. Consider whether recombinant human cystatin C or native preparations better suit your needs. For large-scale procurement, request batch-to-batch consistency data and consider establishing long-term supply agreements to ensure continuity. Pricing varies significantly based on quantity, purity, and certification level, with bulk purchases typically offering better value.
Related Manufacturers
- 主营：ELISA试剂盒、PCR试剂盒、生化试剂盒、胱抑素CELISA试剂盒、蛋白、抗体、细胞、检测试剂盒
- 主营：胱抑素、试剂盒、抗原检测试剂
- 主营：植物胱抑素Celisa试剂盒、试剂盒、人25羟基维生素、人低氧诱导因子
- 主营：科研试剂盒、酶免试剂盒、elisa试剂盒、小鼠胱抑素C、细胞、生物试剂、进口ELISA试剂盒、PCR试剂盒、生化测试盒
- 主营：科研试剂盒、酶免试剂盒、elisa试剂盒、人胱抑素c、生化试剂盒、细胞、生物试剂、进口ELISA试剂盒、PCR试剂盒、生化测试盒
- 主营：ELISA试剂盒、PCR试剂盒、生化试剂盒、胱抑素CELISA试剂盒、蛋白、抗体、细胞
- 主营：显色试剂、化妆品原料、采样管添加剂、胱抑素C抗体、采血管添加剂
- 主营：elisa试剂盒、生化试剂盒、抗体、pcr试剂盒、细胞
- 主营：elisa试剂盒、检测试剂盒、PCR试剂盒
- 主营：胱抑素C、检测试剂盒、elisa试剂盒
- 主营：胱抑素C、试剂盒、ELISA试剂盒、ELISA检测试剂盒
- 主营：Elisa试剂盒、生化试剂盒、蛋白试剂盒、人胱抑素CElisakit、细胞试剂盒
- 主营：胱抑素C试剂盒、elisa试剂盒
- 主营：elisa试剂盒、白细胞介素试剂盒、肿瘤坏死因子试剂盒、胱抑素C、植物检测试剂盒
- 主营：试剂盒、试剂瓶、白吸头、胱抑素C、蓝吸头、黄吸头、实验服务、ELISA免费实验代测、Western实验服务、科研试剂盒