Description
Human von Willebrand factor (VWF) ELISA Kit
The Human Von Willebrand Factor (vWF) ELISA Kit is specifically designed for the precise measurement of vWF levels in human serum, plasma, and cell culture supernatants. This kit offers exceptional sensitivity and specificity, ensuring accurate and consistent results for a variety of research purposes.Von Willebrand Factor is a key glycoprotein involved in blood clotting and platelet adhesion, making it crucial for maintaining hemostasis. Abnormalities in vWF levels are associated with various bleeding disorders, such as von Willebrand disease and thrombotic thrombocytopenic purpura, highlighting the clinical significance of monitoring vWF levels.
By utilizing the Human Von Willebrand Factor ELISA Kit, researchers can gain valuable insights into vWF biology, disease mechanisms, and potential therapeutic strategies. This kit provides a reliable tool for studying vWF-related disorders and advancing our understanding of hemostasis and thrombosis.
| Product Name: | Human von Willebrand factor (VWF) ELISA Kit |
| SKU: | HUEB0874 |
| Size: | 96T |
| Target: | Human von Willebrand factor (VWF) |
| Synonyms: | vWF, F8VWF |
| Assay Type: | Sandwich |
| Detection Method: | ELISA |
| Reactivity: | Human |
| Detection Range: | 3.12-200ng/mL |
| Sensitivity: | 1.58ng/mL |
| Intra CV: | 4.4% | ||||||||||||||||||||
| Inter CV: | 7.9% | ||||||||||||||||||||
| Linearity: |
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| Recovery: |
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| Function: | Important in the maintenance of hemostasis, it promotes adhesion of platelets to the sites of vascular injury by forming a molecular bridge between sub-endothelial collagen matrix and platelet-surface receptor complex GPIb-IX-V. Also acts as a chaperone for coagulation factor VIII, delivering it to the site of injury, stabilizing its heterodimeric structure and protecting it from premature clearance from plasma. |
| Uniprot: | P04275 |
| Sample Type: | Serum, plasma, tissue homogenates, cell culture supernates and other biological fluids |
| Specificity: | Natural and recombinant human von Willebrand factor |
| Sub Unit: | Multimeric. Interacts with F8. |
| Research Area: | Signal Transduction |
| Subcellular Location: | Secreted Secreted Extracellular space Extracellular matrix Localized to storage granules. |
| Storage: | Please see kit components below for exact storage details |
| Note: | For research use only |
| UniProt Protein Function: | VWF: Important in the maintenance of hemostasis, it promotes adhesion of platelets to the sites of vascular injury by forming a molecular bridge between sub-endothelial collagen matrix and platelet-surface receptor complex GPIb-IX-V. Also acts as a chaperone for coagulation factor VIII, delivering it to the site of injury, stabilizing its heterodimeric structure and protecting it from premature clearance from plasma. Defects in VWF are the cause of von Willebrand disease type 1 (VWD1). A common hemorrhagic disorder due to defects in von Willebrand factor protein and resulting in impaired platelet aggregation. Von Willebrand disease type 1 is characterized by partial quantitative deficiency of circulating von Willebrand factor, that is otherwise structurally and functionally normal. Clinical manifestations are mucocutaneous bleeding, such as epistaxis and menorrhagia, and prolonged bleeding after surgery or trauma. Defects in VWF are the cause of von Willebrand disease type 2 (VWD2). A hemorrhagic disorder due to defects in von Willebrand factor protein and resulting in impaired platelet aggregation. Von Willebrand disease type 2 is characterized by qualitative deficiency and functional anomalies of von Willebrand factor. It is divided in different subtypes including 2A, 2B, 2M and 2N (Normandy variant). The mutant VWF protein in types 2A, 2B and 2M are defective in their platelet- dependent function, whereas the mutant protein in type 2N is defective in its ability to bind factor VIII. Clinical manifestations are mucocutaneous bleeding, such as epistaxis and menorrhagia, and prolonged bleeding after surgery or trauma. Defects in VWF are the cause of von Willebrand disease type 3 (VWD3). A severe hemorrhagic disorder due to a total or near total absence of von Willebrand factor in the plasma and cellular compartments, also leading to a profound deficiency of plasmatic factor VIII. Bleeding usually starts in infancy and can include epistaxis, recurrent mucocutaneous bleeding, excessive bleeding after minor trauma, and hemarthroses. |
| UniProt Protein Details: | Protein type:Cell adhesion; Secreted, signal peptide; Extracellular matrix; Motility/polarity/chemotaxis; Secreted Chromosomal Location of Human Ortholog: 12p13.3 Cellular Component: extracellular matrix; proteinaceous extracellular matrix; endoplasmic reticulum; extracellular region; external side of plasma membrane Molecular Function:integrin binding; collagen binding; identical protein binding; protein binding; protein homodimerization activity; protease binding; chaperone binding; immunoglobulin binding; protein N-terminus binding; glycoprotein binding Biological Process: platelet activation; extracellular matrix organization and biogenesis; platelet degranulation; hemostasis; response to wounding; liver development; blood coagulation; cell adhesion; blood coagulation, intrinsic pathway; protein homooligomerization; cell-substrate adhesion; placenta development Disease: Von Willebrand Disease, Type 3; Von Willebrand Disease, Type 1; Von Willebrand Disease, Type 2 |
| NCBI Summary: | The glycoprotein encoded by this gene functions as both an antihemophilic factor carrier and a platelet-vessel wall mediator in the blood coagulation system. It is crucial to the hemostasis process. Mutations in this gene or deficiencies in this protein result in von Willebrand's disease. An unprocessed pseudogene has been found on chromosome 22. [provided by RefSeq, Jul 2008] |
| UniProt Code: | P04275 |
| NCBI GenInfo Identifier: | 317373549 |
| NCBI Gene ID: | 7450 |
| NCBI Accession: | P04275.4 |
| UniProt Secondary Accession: | P04275,Q8TCE8, Q99806, |
| UniProt Related Accession: | P04275 |
| Molecular Weight: | Calculated MW: 38kDa/309kDaObserved MW: Refer to figures |
| NCBI Full Name: | von Willebrand factor |
| NCBI Synonym Full Names: | von Willebrand factor |
| NCBI Official Symbol: | VWF |
| NCBI Official Synonym Symbols: | VWD; F8VWF |
| NCBI Protein Information: | von Willebrand factor; coagulation factor VIII VWF |
| UniProt Protein Name: | von Willebrand factor |
| UniProt Synonym Protein Names: | von Willebrand antigen II |
| Protein Family: | von Willebrand factor |
| UniProt Gene Name: | VWF |
| UniProt Entry Name: | VWF_HUMAN |
| Component | Quantity (96 Assays) | Storage |
| ELISA Microplate (Dismountable) | 8×12 strips | -20°C |
| Lyophilized Standard | 2 | -20°C |
| Sample Diluent | 20ml | -20°C |
| Assay Diluent A | 10mL | -20°C |
| Assay Diluent B | 10mL | -20°C |
| Detection Reagent A | 120µL | -20°C |
| Detection Reagent B | 120µL | -20°C |
| Wash Buffer | 30mL | 4°C |
| Substrate | 10mL | 4°C |
| Stop Solution | 10mL | 4°C |
| Plate Sealer | 5 | - |
Other materials and equipment required:
- Microplate reader with 450 nm wavelength filter
- Multichannel Pipette, Pipette, microcentrifuge tubes and disposable pipette tips
- Incubator
- Deionized or distilled water
- Absorbent paper
- Buffer resevoir
*Note: The below protocol is a sample protocol. Protocols are specific to each batch/lot. For the correct instructions please follow the protocol included in your kit.
Allow all reagents to reach room temperature (Please do not dissolve the reagents at 37°C directly). All the reagents should be mixed thoroughly by gently swirling before pipetting. Avoid foaming. Keep appropriate numbers of strips for 1 experiment and remove extra strips from microtiter plate. Removed strips should be resealed and stored at -20°C until the kits expiry date. Prepare all reagents, working standards and samples as directed in the previous sections. Please predict the concentration before assaying. If values for these are not within the range of the standard curve, users must determine the optimal sample dilutions for their experiments. We recommend running all samples in duplicate.
| Step | |
| 1. | Add Sample: Add 100µL of Standard, Blank, or Sample per well. The blank well is added with Sample diluent. Solutions are added to the bottom of micro ELISA plate well, avoid inside wall touching and foaming as possible. Mix it gently. Cover the plate with sealer we provided. Incubate for 120 minutes at 37°C. |
| 2. | Remove the liquid from each well, don't wash. Add 100µL of Detection Reagent A working solution to each well. Cover with the Plate sealer. Gently tap the plate to ensure thorough mixing. Incubate for 1 hour at 37°C. Note: if Detection Reagent A appears cloudy warm to room temperature until solution is uniform. |
| 3. | Aspirate each well and wash, repeating the process three times. Wash by filling each well with Wash Buffer (approximately 400µL) (a squirt bottle, multi-channel pipette,manifold dispenser or automated washer are needed). Complete removal of liquid at each step is essential. After the last wash, completely remove remaining Wash Buffer by aspirating or decanting. Invert the plate and pat it against thick clean absorbent paper. |
| 4. | Add 100µL of Detection Reagent B working solution to each well. Cover with the Plate sealer. Incubate for 60 minutes at 37°C. |
| 5. | Repeat the wash process for five times as conducted in step 3. |
| 6. | Add 90µL of Substrate Solution to each well. Cover with a new Plate sealer and incubate for 10-20 minutes at 37°C. Protect the plate from light. The reaction time can be shortened or extended according to the actual color change, but this should not exceed more than 30 minutes. When apparent gradient appears in standard wells, user should terminatethe reaction. |
| 7. | Add 50µL of Stop Solution to each well. If color change does not appear uniform, gently tap the plate to ensure thorough mixing. |
| 8. | Determine the optical density (OD value) of each well at once, using a micro-plate reader set to 450 nm. User should open the micro-plate reader in advance, preheat the instrument, and set the testing parameters. |
| 9. | After experiment, store all reagents according to the specified storage temperature respectively until their expiry. |
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.
| Sample Type | Protocol |
| Serum | 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. |
| Plasma | 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. |
| Cell lysates | 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. |
| Tissue homogenates | 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. |
| Tissue lysates | 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. |
| Breast Milk | 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. |
