Description

Omalizumab (Xolair®) ELISA Kit

Enzyme-linked immunosorbent assay (ELISA) for the quantitative determination of Omalizumab (Xolair®) in serum and plasma. Assay Genie omalizumab ELISA has been especially developed for the quantitative analysis omalizumab in serum and plasma samples and is for research use only.

Omalizumab (Xolair®) ELISA Kit test principle

Solid phase enzyme-linked immunosorbent assay (ELISA) based on the sandwich principle. Standards and samples (serum or plasma) are incubated in the microtitre plate coated with the reactant specific for omalizumab (Xolair®). Following incubation wells are washed and then horse radish peroxidase (HRP) conjugate is added and binds to omalizumab. After incubation, the wells are washed, and the bound enzymatic activity is detected by addition of chromogen-substrate. The colour developed is proportional to the amount of omalizumab (Xolair®) in the sample or standard. Results of samples can be determined directly using the standard curve.

Omalizumab (Xolair®) ELISA Product Information

Information	Description
Application	Free drug
Required Volume (uL)	10
Total Time (min)	70
Sample Type	Serum, Plasma
Number of Assays	96
Detection Limit (ng/mL)	10 (ng/mL)
Spike Recovery (%)	85-115%
Shelf Life (year)	1
Alternative Names	IgG1k mAb Xolair

Omalizumab (Xolair®) - Key Information

Omalizumab (Xolair®) mode of action

Omalizumab is a recombinant DNA-derived humanized IgG1k monoclonal antibody that selectively binds to human immunoglobulin E (IgE). Omalizumab (Xolair) is produced by a Chinese hamster ovary cell suspension culture in a nutrient medium containing the antibiotic gentamicin. Omalizumab (Xolair) inhibits the binding of IgE to the high-affinity IgE receptor (FceRI) on the surface of mast cells and basophils. Reduction in surface-bound IgE on FcεRI-bearing cells limits the degree of release of mediators of the allergic response. Omalizumab does not bind to cell surface IgE, so it does not directly activate mast cells or basophils. The decrease in free IgE levels results in a reduced amount of FcεRI receptors on mast cells, basophils, and antigen-presenting cells.

Omalizumab (Xolair®) uses

Omalizumab is used to treat severe, persisten asthma. Omalizumab binds to IgE (a class of antibodies normally secreted in allergic responses), which prevents their binding to mast cells and basophils. Most likely removed by opsonization via the reticuloendothelial system. Liver elimination of IgG includes degradation in the liver reticuloendothelial system (RES) and endothelial cells. Intact IgG is also excreted in bile. Liver elimination of IgG includes degradation in the liver reticuloendothelial system (RES) and endothelial cells. Intact IgG is also excreted in bile.

Omalizumab (Xolair®) ELISA Kit Contents

Size	Kit Contents
1 x 12 x 8	Microtiter Plate Break apart strips. Microtiter plate with 12 rows each of 8 wells coated with reactant
7 x 0.3 mL	Omalizumab Standards A-E, High Level Control, Low Level Control 1000; 300; 100; 30 and 0 ng/mL Ready to use. Used for construction of the standard curve. Contains omalizumab (Xolair®), human serum, stabilizer and <0.1% NaN3
1 x 50 mL	Assay Buffer Blue coloured. Ready to use. Contains proteins and <0.1% NaN3.
1 x 12 mL	Peroxidase Conjugate Red coloured. Ready to use. Contains horse radish peroxidase (HRP) and stabilizers.
1 x 12 mL	TMB Substrate Solution Ready to use. Contains TMB
1 x 12 mL	TMB Stop Solution Ready to use. 1N HCl
1 x 50 mL	Wash Buffer concentrate (20x) Contains Buffer with Tween 20.
2 x 1	Adhesive Foil For covering of Microtiter Plate during incubation.

Omalizumab (Xolair®) ELISA Protocol

Steps	Protocol
1	Pipette 100µl of Assay Buffer non-exceptionally into each of the wells to be used.
2	Pipette 10 µL of each ready-to use Standards, High Level Control, Low Level Control and Diluted Samples into the respective wells of microtiter plate. Wells A1: Standard A B1: Standard B C1: Standard C D1: Standard D E1: Standard E F1: High Level Control G1: Low Level Control H1 and on: Sample (Serum / Plasma)
3	Cover the plate with adhesive foil. Incubate 30 min at room temperature (18- 25°C).
4	Remove adhesive foil. Discard incubation solution. Wash plate 3 times each with 300µL of diluted. Wash Buffer. Remove excess solution by tapping the inverted plate on a paper towel.
5	Pipette 100 µL of ready-to use Peroxidase Conjugate into each well.
6	Cover the plate with adhesive foil. Incubate 30 min at room temperature (18- 25°C).
7	Remove adhesive foil. Discard incubation solution. Wash plate 3 times each with 300 µL of diluted Wash Buffer. Remove excess solution by tapping the inverted plate on a paper towel.
8	Pipette 100 µL of TMB Substrate Solution into each well.
9	Incubate 10 min (without adhesive foil) at room temperature (18-25°C) in the dark
10	Stop the substrate reaction by adding 100 µL of Stop Solution into each well. Briefly mix contents by gently shaking the plate. Colour changes from blue to yellow.
11	Measure optical density with a photometer at 450/650 nm within 30 min after pipetting of the Stop Solution.

Trademarks

Xolair® is a trademark of Novartis AG.