Abcam, ab283970, Human Cystatin S ELISA Kit

Size: 1 x 96Tests
Human Cystatin S ELISA Kit is a Sandwich (quantitative) ELISA for the measurement of Human Cystatin S in Human in Cell Culture Media, Biofluids samples.
Key facts
Detection method:Colorimetric,
Sample types:Cell culture supernatant, Saliva,
Reacts with:Human,
Assay type:Sandwich (quantitative),
Sensitivity:= 7.2 pg/mL,
Range:0.016 - 1 ng/mL,
Assay time:4h,
Assay Platform:Pre-coated microplate (12 x 8 well strips)

Product details:
The Human Cystatin S ELISA Kit (ab283970) is designed for detection of Cystatin-S (CST4) in human saliva and cell culture samples.
This assay employs a quantitative sandwich enzyme immunoassay technique that measures human CST4 in approximately 4 hours. A polyclonal antibody specific for human CST4 has been pre-coated onto a 96- well microplate with removable strips. CST4 in standards and samples is sandwiched by the immobilized antibody and a biotinylated polyclonal antibody specific for human CST4, which is recognized by a streptavidin-peroxidase (SP) conjugate. All unbound material is washed away and a peroxidase enzyme substrate is added. The color development is stopped and the intensity of the color is measured.

Properties and Storage Information:
Shipped at conditions-Blue Ice, Appropriate short-term storage conditions--20°C, Appropriate long-term storage conditions-Multi, Storage information-Please refer to protocols

Supplementary Information:
This supplementary information is collated from multiple sources and compiled automatically.
Cystatin S also known as CST4 is a cysteine protease inhibitor with a molecular mass of approximately 14 kDa. This protein belongs to the cystatin superfamily which is a group of proteins that inhibit proteases such as cathepsins. Cystatin S is mainly expressed in human saliva tears and other bodily fluids where it plays a significant role in protecting tissues from protease activity. Expression levels of cystatin S vary across tissues and can influence its inhibitory functions.
Biological function summary
Cystatin S regulates proteolytic activity by inhibiting enzymes like papain and cathepsins. This protein aids in maintaining the equilibrium between proteases and their inhibitors which is essential for protecting extracellular matrices. Cystatin S does not form part of a larger complex but functions independently to provide defense against unwanted proteolysis in the oral cavity and other environments.
Pathways
Cystatin S interacts with proteolytic pathways that handle extracellular matrix degradation and inflammatory responses. Inhibiting cathepsins within these pathways counters tissue destruction and contributes to cellular homeostasis. Cystatin-related proteins such as cystatin C share similar inhibitory roles indicating their importance in overlapping regulatory networks.
Aberrant expression or function of cystatin S associates with conditions like periodontitis and Sjögren's syndrome. In periodontitis imbalance in protease inhibition leads to periodontal tissue breakdown. Sjögren's syndrome characterized by reduced secretion of tears and saliva links to altered cystatin S levels and its interaction with other protease inhibitors like cystatin C. Both disorders highlight the significance of cystatin S in maintaining tissue integrity.