Human CD21 ELISA Kit is a single-wash 90-min Simplestep used to quantify Human CD21 with a sensitivity of 3.85 pg/ml. The assay uses a simple mix-wash-read protocol with just one incubation and one wash step.
- Colorimetric Sandwich ELISA - 450 nm readout : works on any standard plate reader
- Design your own immunoassay: we also offer the conjugation-ready antibody pair
Images
Key facts
- Detection method
- Colorimetric
- Sample types
- Heparin Plasma, Cell culture supernatant, Serum, Cell Lysate, EDTA Plasma
- Assay type
- Sandwich (quantitative)
- Reactive species
- Human
- Range
- 31.25 - 2000 pg/mL
- Assay time
- 1h 30m
- Sensitivity
- = 3.85 pg/mL
Reactivity data
| Application | Reactivity | Dilution info | Notes |
|---|---|---|---|
Application sELISA | Reactivity Reacts | Dilution info - | Notes - |
Target data
Function
Serves as a receptor for various ligands including complement component CD3d, HNRNPU OR IFNA1 (PubMed:1849076, PubMed:21527715, PubMed:7753047). When C3d is bound to antigens, attaches to C3d on B-cell surface and thereby facilitates the recognition and uptake of antigens by B-cells (PubMed:21527715). This interaction enhances B-cell activation and subsequent immune responses. Forms a complex with several partners on the surface of B-cells including CD19, FCRL5 and CD81, to form the B-cell coreceptor complex that plays a crucial role in B-cell activation and signaling (PubMed:1383329, PubMed:30107486). Induces also specific intracellular signaling separately from the BCR and CD19 by activating the tyrosine kinase SRC, which then phosphorylates nucleolin/NCL and triggers AKT and GSK3 kinase activities in a SYK/CD19-independent manner (PubMed:12938232). Acts as a ligand for CD23 (FcepsilonRII), a low-affinity receptor for IgE, which is expressed on B-cells and other immune cells, and thus participates in the regulation of IgE production (PubMed:1386409). (Microbial infection) Acts as a receptor for Epstein-Barr virus.
Alternative names
CD21, C3DR, CR2, Complement receptor type 2, Cr2, Complement C3d receptor, Epstein-Barr virus receptor, EBV receptor
What's included?
Recommended products
Human CD21 ELISA Kit is a single-wash 90-min Simplestep used to quantify Human CD21 with a sensitivity of 3.85 pg/ml. The assay uses a simple mix-wash-read protocol with just one incubation and one wash step.
- Colorimetric Sandwich ELISA - 450 nm readout : works on any standard plate reader
- Design your own immunoassay: we also offer the conjugation-ready antibody pair
Key facts
- Detection method
- Colorimetric
- Sample types
- Heparin Plasma, Cell culture supernatant, Serum, Cell Lysate, EDTA Plasma
- Assay type
- Sandwich (quantitative)
- Reactive species
- Human
- Range
- 31.25 - 2000 pg/mL
- Assay time
- 1h 30m
- Assay Platform
- Pre-coated microplate (12 x 8 well strips)
- Sensitivity
- = 3.85 pg/mL
Precision
Intra assay
| Sample | n | mean | SD | C.V. |
|---|---|---|---|---|
Sample Serum | n 8 | mean - | SD - | C.V. 2.8 |
Inter assay
| Sample | n | mean | SD | C.V. |
|---|---|---|---|---|
Sample Serum | n 3 | mean - | SD - | C.V. 3.2 |
Recovery
Sample specific recovery
| Sample type | Average % | Range |
|---|---|---|
Sample type Cell culture supernatant | Average % = 98 | Range 88 - 106 % |
Sample type Serum | Average % = 100 | Range 92 - 104 % |
Sample type EDTA Plasma | Average % = 104 | Range 102 - 107 % |
Sample type Heparin Plasma | Average % = 89 | Range 85 - 92 % |
Sample type Citrate plasma | Average % = 93 | Range 90 - 96 % |
Storage
- Shipped at conditions
- Blue Ice
- Appropriate short-term storage conditions
- +4°C
- Appropriate long-term storage conditions
- +4°C
- Storage information
- +4°C
Notes
Human CD21 ELISA kit (ab284613) is a single-wash 90 min sandwich ELISA designed for the quantitative measurement of Human CD21 protein in human serum, plasma, cell and tissue extract samples. It uses our proprietary SimpleStep ELISA® technology. Quantitate Human CD21 with 3.85 pg/mL sensitivity.
SimpleStep ELISA® technology employs capture antibodies conjugated to an affinity tag that is recognized by the monoclonal antibody used to coat our SimpleStep ELISA® plates. This approach to sandwich ELISA allows the formation of the antibody-analyte sandwich complex in a single step, significantly reducing assay time. See the SimpleStep ELISA® protocol summary in the image section for further details. Our SimpleStep ELISA® technology provides several benefits:
-Single-wash protocol reduces assay time to 90 minutes or less
-High sensitivity, specificity and reproducibility from superior antibodies
-Fully validated in biological samples
-96-wells plate breakable into 12 x 8 wells strips
A 384-well SimpleStep ELISA® microplate (Pre-coated 384 well Microplate SimpleStep ELISA® ab203359) is available to use as an alternative to the 96-well microplate provided with SimpleStep ELISA® kits.
Abcam has not and does not intend to apply for the REACH Authorisation of customers' uses of products that contain European Authorisation list (Annex XIV) substances.
It is the responsibility of our customers to check the necessity of application of REACH Authorisation, and any other relevant authorisations, for their intended uses.
Supplementary info
- This supplementary information is collated from multiple sources and compiled automatically.
- Activity summary
CD21 also known as complement receptor type 2 (CR2) or BU32 is a protein primarily expressed on the surface of B cells and some T cells. It functions as a receptor for complement component C3d EBV (Epstein-Barr Virus) and IFN-α. CD21 weighs approximately 145 kDa and belongs to the membrane protein family. Detection of CD21 can be done via immunohistochemistry (IHC) and blood tests. This marker is valuable for identifying cell populations that have roles in immune responses.
- Biological function summary
Complement receptor type 2 is key in the immune system by facilitating B cell activation and proliferation. CD21 forms complexes with CD19 and CD81 increasing the sensitivity of B cells to antigens. This interaction enhances signal transduction enabling B lymphocytes to respond effectively to pathogens. The protein also plays a role in regulating immune tolerance and maintaining humoral immunity being important not only in immune defense but also in preventing autoimmunity.
- Pathways
CD21 interacts with complement activation and immune response pathways. It connects with CD19 in a pivotal role where it further amplifies signaling in B lymphocytes. This interaction strengthens the downstream signaling of BCR (B cell receptor) important for antibody production. CD21 contributes to bridging the innate and adaptive immunological pathways by engaging components like C3d.
- Associated diseases and disorders
CD21 shows significant relevance in systemic lupus erythematosus (SLE) and some B cell lymphomas. Deficiencies or mutations in CD21 can lead to defective immune responses and increased susceptibility to autoimmune conditions such as SLE where CD19 is also implicated. Furthermore in Epstein-Barr Virus infections CD21 serves as an entry receptor facilitating pathogen establishment which can result in chronic conditions or even malignancies.
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6 product images
Sandwich ELISA - Human CD21 ELISA Kit (ab284613)
Example of human CD21 standard curve in Sample Diluent NS.
Example of human CD21 standard curve. Background-subtracted data values (mean +/- SD) are graphed.
Sandwich ELISA - Human CD21 ELISA Kit (ab284613)
Example of human CD21 standard curve in 1X Cell Extraction Buffer PTR.
Example of human CD21 standard curve. Background-subtracted data values (mean +/- SD) are graphed.
Sandwich ELISA - Human CD21 ELISA Kit (ab284613)
Interpolated concentrations of human CD21 in serum, plasma (citrate), plasma (EDTA), and plasma (heparin).
Interpolated concentration of native CD21 was measured in duplicate at different sample concentrations. Undiluted samples are 1:100 serum, plasma (citrate), plasma (EDTA), and plasma (heparin). The interpolated dilution factor corrected values are plotted (mean +/- SD, n=2). Sample dilutions are made in Sample Diluent NS.
Sandwich ELISA - Human CD21 ELISA Kit (ab284613)
Interpolated concentrations of human CD21 in Daudi cell culture supernatant.
Interpolated concentration of native CD21 was measured in duplicate at different sample concentrations. Undiluted samples are 1:2 Daudi cell culture supernatant. The interpolated dilution factor corrected values are plotted (mean +/- SD, n=2). Sample dilutions are made in Sample Diluent NS.
Sandwich ELISA - Human CD21 ELISA Kit (ab284613)
Interpolated concentrations of human CD21 in Daudi cell extract and lymph node tissue extract.
Interpolated concentration of native CD21 was measured in duplicate at different sample concentrations. Undiluted samples are as follows: Daudi cell extract 25 μg/mL and lymph node tissue extract 1 μg/mL. The interpolated dilution factor corrected values are plotted (mean +/- SD, n=2). Sample dilutions are made in 1X Cell Extraction Buffer PTR.
Sandwich ELISA - Human CD21 ELISA Kit (ab284613)
Interpolated concentrations of CD21 in normal human serum donors.
Serum diluted 1:200 of ten individual healthy human female donors was measured in duplicate. Interpolated dilution factor corrected values are plotted (mean +- SD, n=2). The mean CD21 concentration was determined to be 147.22 ng/mL with a range of 54.21 – 205.02 ng/mL.
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