Cystatin S / CST4 Antibody

Cystatin S / CST4 Antibody Datasheet

Cystatin S / CST4 Antibody Product Information

• Immunogen: Recombinant Human Cystatin S / CST4 protein (Catalog#11542-H08H)
• Antibody Type: Rabbit Monoclonal Antibody ( Rabbit mAb Service Platform )
• Clone ID: 006
• Ig Type: Rabbit IgG
• Formulation: 0.2 μm filtered solution in PBS with 5% trehalose
• Preparation: This antibody was obtained from a rabbit immunized with purified, recombinant Human Cystatin S / CST4 (rh Cystatin S / CST4; Catalog#11542-H08H; NP_001890.1; Met 1-Ala 141).

Cystatin S / CST4 Antibody Usage Guide

• Specificity: Human Cystatin S / CST4
• Western blot: This antibody can be used at 1-2 μg/mL with the appropriate secondary reagents to detect Human CST4 in WB.
• Direct ELISA: This antibody can be used at 0.1-0.2 μg/mL with the appropriate secondary reagents to detect Human CST4. The detection limit for Human CST4 is approximately 0.195 ng/well.
• Storage: This antibody can be stored at 2℃-8℃ for one month without detectable loss of activity. Antibody products are stable for twelve months from date of receipt when stored at -20℃ to -70℃. Preservative-Free.
  Sodium azide is recommended to avoid contamination (final concentration 0.05%-0.1%). It is toxic to cells and should be disposed of properly. Avoid repeated freeze-thaw cycles.

Cystatin S / CST4 Antibody Background

Cystatin-S, also known as Cystatin-4, Salivary acidic protein 1, Cystatin-SA-III and CST4, is a secreted protein which belongs to thecystatin family. Cystatin-4 / CST4 is expressed in submandibular and sublingual saliva but not in parotid saliva (at protein level). It is also expressed in saliva, tears, urine and seminal fluid. The cystatin superfamily encompasses proteins that contain multiple cystatin-like sequences. Some of the members are active cysteine protease inhibitors, while others have lost or perhaps never acquired this inhibitory activity. There are three inhibitory families in the superfamily, including the type 1 cystatins (stefins), type 2 cystatins and the kininogens. The type 2 cystatin proteins are a class of cysteine proteinase inhibitors found in a variety of human fluids and secretions. Cystatin-4 / CST4 strongly inhibits papain and ficin, partially inhibits stem bromelain and bovine cathepsin C, but does not inhibit porcine cathepsin B or clostripain. Papain is inhibited non-competitively. Cystatin-4 / CST4 is an S-type cystatin, based on its high level of expression in saliva, tears and seminal plasma. The specific role in these fluids is unclear but antibacterial and antiviral activity is present, consistent with a protective function.

References

1. Saitoh,E. et al., 1992, Agents Actions Suppl. 38 (Pt 1): 340-8.
2. Saitoh E, et al., 1992, Biomed Biochim Acta. 50 (4-6): 599-605.
3. Baron A, et al., 2000, Oral diseases. 5 (3): 234-40.
4. Dickinson, DP. et al., 2002, DNA Cell Biol. 21 (1): 47-65.