| Description|| |
S100A9 is a calcium- and zinc-binding protein which plays a prominent role in the regulation of inflammatory processes and immune response. It can induce neutrophil chemotaxis, adhesion, can increase the bactericidal activity of neutrophils by promoting phagocytosis via activation of SYK, PI3K/AKT, and ERK1/2 and can induce degranulation of neutrophils by a MAPK-dependent mechanism. Predominantly found as calprotectin (S100A8/A9) which has a wide plethora of intra- and extracellular functions. The intracellular functions include: facilitating leukocyte arachidonic acid trafficking and metabolism, modulation of the tubulin-dependent cytoskeleton during migration of phagocytes and activation of the neutrophilic NADPH-oxidase. Activates NADPH-oxidase by facilitating the enzyme complex assembly at the cell membrane, transferring arachidonic acid, an essential cofactor, to the enzyme complex and S100A8 contributes to the enzyme assembly by directly binding to NCF2/P67PHOX. The extracellular functions involve proinfammatory, antimicrobial, oxidant-scavenging and apoptosis-inducing activities. Its proinflammatory activity includes recruitment of leukocytes, promotion of cytokine and chemokine production, and regulation of leukocyte adhesion and migration. Acts as an alarmin or a danger associated molecular pattern (DAMP) molecule and stimulates innate immune cells via binding to pattern recognition receptors such as Toll-like receptor 4 (TLR4) and receptor for advanced glycation endproducts (AGER). Binding to TLR4 and AGER activates the MAP-kinase and NF-kappa-B signaling pathways resulting in the amplification of the proinflammatory cascade. Has antimicrobial activity towards bacteria and fungi and exerts its antimicrobial activity probably via chelation of Zn2+ which is essential for microbial growth. Can induce cell death via autophagy and apoptosis and this occurs through the cross-talk of mitochondria and lysosomes via reactive oxygen species (ROS) and the process involves BNIP3. Can regulate neutrophil number and apoptosis by an anti-apoptotic effect; regulates cell survival via ITGAM/ITGB and TLR4 and a signaling mechanism involving MEK-ERK. Its role as an oxidant scavenger has a protective role in preventing exaggerated tissue damage by scavenging oxidants. Can act as a potent amplifier of inflammation in autoimmunity as well as in cancer development and tumor spread. Has transnitrosylase activity; in oxidatively-modified low-densitity lipoprotein (LDL(ox))-induced S-nitrosylation of GAPDH on 'Cys-247' proposed to transfer the NO moiety from NOS2/iNOS to GAPDH via its own S-nitrosylated Cys-3. The iNOS-S100A8/A9 transnitrosylase complex is proposed to also direct selective inflammatory stimulus-dependent S-nitrosylation of multiple targets such as ANXA5, EZR, MSN and VIM by recognizing a
Human S100A9 ELISA Kit Protocol
The below protocol is a sample protocol for Human S100A9 ELISA Kit using a biotinylated detection antibody and streptavidin-HRP. Sandwich ELISAs allow for the detection and quantification of an analyte in a sample by using known analyte concentrations as standards and plotting absorbance of known concentrations vs known standard concentrations. This allows the researcher to calculate the amount of Human S100A9 present in their sample.
Before adding to wells, equilibrate the SABC working solution and TMB substrate for at least 30 min at 37 °C. When diluting samples and reagents, they must be mixed completely and evenly. It is recommended to plot a standard curve for each test.
|1.||Set standard, test sample and control (zero) wells on the pre-coated plate respectively, and then, record their positions. It is recommended to measure each standard and sample in duplicate. Wash plate 2 times before adding standard, sample and control (zero) wells!|
|2.||Aliquot 0.1ml standard solutions into the standard wells.|
|3.||Add 0.1 ml of Sample / Standard dilution buffer into the control (zero) well.|
|4.||Add 0.1 ml of properly diluted sample ( Human serum, plasma, tissue homogenates and other biological fluids.) into test sample wells.|
|5.||Seal the plate with a cover and incubate at 37 °C for 90 min.|
|6.||Remove the cover and discard the plate content, clap the plate on the absorbent filter papers or other absorbent material. Do NOT let the wells completely dry at any time. Wash plate X2.|
|7.||Add 0.1 ml of Biotin- detection antibody working solution into the above wells (standard, test sample & zero wells). Add the solution at the bottom of each well without touching the side wall.|
|8.||Seal the plate with a cover and incubate at 37°C for 60 min.|
|9.||Remove the cover, and wash plate 3 times with Wash buffer. Let wash buffer rest in wells for 1 min between each wash.|
|10.||Add 0.1 ml of SABC working solution into each well, cover the plate and incubate at 37°C for 30 min.|
|11.||Remove the cover and wash plate 5 times with Wash buffer, and each time let the wash buffer stay in the wells for 1-2 min.|
|12.||Add 90 µl of TMB substrate into each well, cover the plate and incubate at 37°C in dark within 10-20 min. (Note: This incubation time is for reference use only, the optimal time should be determined by end user.) And the shades of blue can be seen in the first 3-4 wells (with most concentrated standard solutions), the other wells show no obvious color.|
|13.||Add 50 µl of Stop solution into each well and mix thoroughly. The color changes into yellow immediately.|
|14.|| Read the O.D. absorbance at 450 nm in a microplate reader immediately after adding the stop solution.|
Human S100A9 ELISA Kit components
|ELISA Microplate(Dismountable)||8×12 strips||4°C for 6 months|
|Sample/Standard Dilution Buffer||20ml||4°C|
|Biotin-labeled Antibody(Concentrated)||120ul||4°C (Protect from light)|
|Antibody Dilution Buffer||10ml||4°C|
|HRP-Streptavidin Conjugate(SABC)||120ul||4°C (Protect from light)|
|SABC Dilution Buffer||10ml||4°C|
|TMB Substrate||10ml||4°C (Protect from light)|
|Plate Sealer||5 ||-|
Other materials and equipment required:The ELISA Genie Human S100A9 ELISA Kit will require other equipment and materials to carry out the assay. Please see list below for further details.
- Microplate reader with 450 nm wavelength filter
- Multichannel Pipette, Pipette, microcentrifuge tubes and disposable pipette tips
- Deionized or distilled water
- Absorbent paper
- Buffer resevoir
When carrying out an ELISA assay it is important to prepare your samples in order to achieve the best possible results. Below we have a list of procedures for the preparation of samples for different sample types.
If using serum separator tubes, allow samples to clot for 30 minutes at room temperature. Centrifuge for 10 minutes at 1,000x g. Collect the serum fraction and assay promptly or aliquot and store the samples at -80°C. Avoid multiple freeze-thaw cycles.
If serum separator tubes are not being used, allow samples to clot overnight at 2-8°C. Centrifuge for 10 minutes at 1,000x g. Remove serum and assay promptly or aliquot and store the samples at -80°C. Avoid multiple freeze-thaw cycles.
Collect plasma using EDTA or heparin as an anticoagulant. Centrifuge samples at 4°C for 15 mins at 1000 × g within 30 mins of collection. Collect the plasma fraction and assay promptly or aliquot and store the samples at -80°C. Avoid multiple freeze-thaw cycles. Note: Over haemolysed samples are not suitable for use with this kit.
Urine & Cerebrospinal Fluid
Collect the urine (mid-stream) in a sterile container, centrifuge for 20 mins at 2000-3000 rpm. Remove supernatant and assay immediately. If any precipitation is detected, repeat the centrifugation step. A similar protocol can be used for cerebrospinal fluid.
Cell culture supernatant
Collect the cell culture media by pipette, followed by centrifugation at 4°C for 20 mins at 1500 rpm. Collect the clear supernatant and assay immediately.
Solubilize cells in lysis buffer and allow to sit on ice for 30 minutes. Centrifuge tubes at 14,000 x g for 5 minutes to remove insoluble material. Aliquot the supernatant into a new tube and discard the remaining whole cell extract. Quantify total protein concentration using a total protein assay. Assay immediately or aliquot and store at ≤ -20 °C.
The preparation of tissue homogenates will vary depending upon tissue type. Rinse tissue with 1X PBS to remove excess blood & homogenize in 20ml of 1X PBS (including protease inhibitors) and store overnight at ≤ -20°C. Two freeze-thaw cycles are required to break the cell membranes. To further disrupt the cell membranes you can sonicate the samples. Centrifuge homogenates for 5 mins at 5000xg. Remove the supernatant and assay immediately or aliquot and store at -20°C or -80°C.
Rinse tissue with PBS, cut into 1-2 mm pieces, and homogenize with a tissue homogenizer in PBS. Add an equal volume of RIPA buffer containing protease inhibitors and lyse tissues at room temperature for 30 minutes with gentle agitation. Centrifuge to remove debris. Quantify total protein concentration using a total protein assay. Assay immediately or aliquot and store at ≤ -20 °C.
Collect milk samples and centrifuge at 10,000 x g for 60 min at 4°C. Aliquot the supernatant and assay. For long term use, store samples at -80°C. Minimize freeze/thaw cycles.
Human S100A9 ELISA Kit Protein Information
|UniProt Protein Function:||S100A9: a calcium-binding regulatory protein of the S-100 family expressed by macrophages in acutely inflammated tissues and in chronic inflammations. May be an inhibitor of protein kinases. Also expressed in epithelial cells constitutively or induced during dermatoses. May interact with components of the intermediate filaments in monocytes and epithelial cells. Interacts with CEACAM3 in a calcium-dependent manner.|
|UniProt Protein Details:|
Chromosomal Location of Human Ortholog: 1q21
Cellular Component: cytoskeleton; cytosol; extracellular region; extracellular space; nucleus; plasma membrane
Molecular Function:arachidonic acid binding; calcium ion binding; microtubule binding; protein binding; RAGE receptor binding; signal transducer activity; zinc ion binding
Biological Process: activation of NF-kappaB transcription factor; autophagy; caspase activation; cell-cell signaling; chemokine production; cytokine production; defense response to bacterium; defense response to fungus; inflammatory response; leukocyte migration during inflammatory response; neutrophil chemotaxis; positive regulation of cell growth; positive regulation of inflammatory response; regulation of cytoskeleton organization and biogenesis; sequestering of zinc ion
|NCBI Summary:||The protein encoded by this gene is a member of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm and/or nucleus of a wide range of cells, and involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. S100 genes include at least 13 members which are located as a cluster on chromosome 1q21. This protein may function in the inhibition of casein kinase and altered expression of this protein is associated with the disease cystic fibrosis. This antimicrobial protein exhibits antifungal and antibacterial activity. [provided by RefSeq, Nov 2014]|
|NCBI GenInfo Identifier:||115444|
|NCBI Gene ID:||6280|
|UniProt Secondary Accession:||P06702,Q6FGA1, Q9NYM0, Q9UCJ1, D3DV36,|
|UniProt Related Accession:||P06702|
|Molecular Weight:||13,242 Da|
|NCBI Full Name:||Protein S100-A9|
|NCBI Synonym Full Names:||S100 calcium binding protein A9|
|NCBI Official Symbol:||S100A9Ã Ã |
|NCBI Official Synonym Symbols:||MIF; NIF; P14; CAGB; CFAG; CGLB; L1AG; LIAG; MRP14; 60B8AG; MAC387Ã Ã |
|NCBI Protein Information:||protein S100-A9|
|UniProt Protein Name:||Protein S100-A9|
|UniProt Synonym Protein Names:||Calgranulin-B; Calprotectin L1H subunit; Leukocyte L1 complex heavy chain; Migration inhibitory factor-related protein 14; MRP-14; p14; S100 calcium-binding protein A9|
|UniProt Gene Name:||S100A9Ã Ã |
|UniProt Entry Name:||S10A9_HUMAN|