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Recombinant Human CD20 / MS4A1 Full Length Protein, His Tag (HEK293), 100µg  

Recombinant Human CD20 / MS4A1 Full Length Protein, His Tag (HEK293), 100µg

Recombinant Human CD20 / MS4A1 Full Length Protein, contains AA Met 1 - Pro 297, produced in human 293 cells (HEK293), His Tag

Synonym
Recombinant human protein, MS4A1, CD20, MS4A-1

More details

CD0-H52H3-100

Availability: within 7 days

2 900,00 €

Background
B-lymphocyte antigen CD20 is also known as B-lymphocyte surface antigen B1, Leukocyte surface antigen Leu-16, Membrane-spanning 4-domains subfamily A member 1 and MS4A1, is an activated-glycosylated phosphoprotein expressed on the surface of all B-cells beginning at the pro-B phase (CD45R+, CD117+) and progressively increasing in concentration until maturity. CD20 is expressed on all stages of B cell development except the first and last; it is present from late pro-B cells through memory cells, but not on either early pro-B cells or plasma blasts and plasma cells. It is found on B-cell lymphomas, hairy cell leukemia, B-cell chronic lymphocytic leukemia, and melanoma cancer stem cells. The protein has no known natural ligand and its function is to enable optimal B-cell immune response, specifically against T-independent antigens. It is suspected that it acts as a calcium channel in the cell membrane. CD20 / MS4A1 is the target of the monoclonal antibodies (mAb) rituximab, Ibritumomab tiuxetan, and tositumomab, which are all active agents in the treatment of all B cell lymphomas and leukemias. Defects in CD20 / MS4A1 are the cause of immunodeficiency common variable type 5 (CVID5); also called antibody deficiency due to CD20 defect. CVID5 is a primary immunodeficiency characterized by antibody deficiency, hypogammaglobulinemia, recurrent bacterial infections and an inability to mount an antibody response to antigen.

Source
Recombinant Human CD20 Full Length, His Tag, HEK293 (CD0-H52H3) is expressed from human 293 cells (HEK293). It contains AA Met 1 - Pro 297 (Accession # P11836-1).

Molecular Characterization
This protein carries a polyhistidine tag at the C-terminus. The protein has a calculated MW of 35.2 kDa. The protein migrates as 40 kDa under reducing (R) condition (SDS-PAGE) due to glycosylation.

Endotoxin
Less than 1.0 EU per μg by the LAL method.

Purity
>90% as determined by SDS-PAGE.

Formulation
Delivered as bulk protein in a 0.2 μm filtered solution of 50 mM HEPES, 150 mM NaCl, DDM, CHS, pH 7.5 with Glycerol as protectant.

Reconstitution
See Certificate of Analysis for details of reconstitution instruction and specific concentration.

Bioactivity
Immobilized Rituximab at 2 μg/mL (100 μL/well) can bind Human CD20 Full Length, His Tag, HEK293 (Cat. No. CD0-H52H3) with a linear range of 2-16 ng/mL (in presence of DDM and CHS) (QC tested).

Immobilized Ofatumumab at 10 μg/mL (100 μL/well) can bind Human CD20 Full Length, His Tag, HEK293 (Cat. No. CD0-H52H3) with a linear range of 2-31 ng/mL (in presence of DDM and CHS) (Routinely tested).

MabThera® (Rituximab) captured on CM5 chip via Anti-human IgG Fc antibodies surface can bind Human CD20 Full Length, His Tag, HEK293 (Cat. No. CD0-H52H3) with an affinity constant of 1.77 nM as determined in a SPR assay (in presence of DDM and CHS) (Biacore T200) (Routinely tested).

Ofatumumab (Human IgG1) captured on CM5 chip via Anti-human IgG Fc antibodies surface can bind Human CD20 Full Length, His Tag, HEK293 (Cat. No. CD0-H52H3) with an affinity constant of 3.57 nM as determined in a SPR assay (in presence of DDM and CHS) (Biacore T200) (Routinely tested).

Loaded MabThera® (Rituximab) on ProteinA Biosensor, can bind Human CD20 Full Length, His Tag, HEK293 (Cat. No. CD0-H52H3) with an affinity constant of 8.1 nM as determined in BLI assay (ForteBio Octet Red96e) (Routinely tested).

Storage
Avoid repeated freeze-thaw cycles. No activity loss was observed after storage at:
In lyophilized state for 1 year (4°C-8°C); After reconstitution under sterile conditions for 1 month (4°C-8°C) or 3 months (-20°C to -70°C).

References

(1) Walport M, et al., 2008, Janeway's Immunobiology (7th ed.). New York: Garland Science.
(2) Bonilla FA, Bona CA., 1996, Textbook of Immunology. Boca Raton: CRC. p. 102.
(3) Cragg MS., 2005., Curr. Dir. Autoimmun. 8: 140–74.