Recombinant anti-CD20 antibody (Rituximab biosimilar - IgG1NQ isotype)

Non-glycosylated monoclonal human IgG1 antibody against human CD20

Anti-hCD20-hIgG1NQ features the variable region of rituximab and a mutated constant region of the human IgG1 isotype.
Rituximab is a mouse/human chimeric monoclonal antibody that targets the CD20 antigen found on the surface of malignant and normal B lymphocytes. Binding of rituximab to CD20 results in cell destruction through different mechanisms including direct signaling of apoptosis, complement activation, and cell-mediated cytotoxicity. Rituximab has been approved by the FDA to treat various lymphoid malignancies, including B-cell non-Hodgkin's lymphoma and B-cell chronic lymphocytic leukemia.

Anti-hCD20-hIgG1NQ contains a N-glycosylation mutation of the constant region of the human IgG1 where potential asparagine (N) glycosylation sites are substituted by glutamine (Q) residues resulting in the production of a non-glycosylated antibody. Glycosylation of an antibody does not affect antigen binding but is essential for Fc receptor-mediated activity [1]. In non-glycosylated antibodies, the effector mechanisms mediated through the Fc receptor types (FcgRI, FcgRII, FcgRIII) and the C1q component of complement are severely compromised or ablated [2].

Anti-hCD20-hIgG1NQ was generated by recombinant DNA technology. It has been produced in Chinese hamster ovary (CHO) cells and purified by affinity chromatography with protein G.

More isotypes of this antibody are available and can be used for comparison of biological activities such as ADCC (see below or in the 'upon request' section). InvivoGen also provides type I and type II anti-hCD20 mAbs featuring the variable regions of Ofatumumab or Obinutuzumab, with either native or engineered Fc regions.

Réferences:

1. Arnold J. et al., 2007. The impact of glycosylation on the biological function and structure of human immunoglobulins. Annu Rev Immunol 25:21-50.
2. Jefferis R., 2009. Glycosylation as a strategy to improve antibody-based therapeutics. Nat Rev Drug Discov. 8(3):226-34.

Figures

Comparison of ADCC potency for native and engineered anti-human CD20 antibody isotypes: Raji-Null cells were incubated with gradient concentrations of Anti-hCD20 or Anti-β-galactosidase (β-gal) mAbs for 1 hour. Jurkat-Lucia™ NFAT-CD16 effector cells were then co-incubated with targets cells for 6 hours. NFAT activation, reflecting the induced ADCC response, was assessed by determining Lucia luciferase activity in the supernatant using QUANTI-Luc™. Percentages of the maximal response normalized to the IgG1 isotype are shown

Specifications

Target: Human CD20

Clonality: Non-glycosylated monoclonal antibody

Clone: Rituximab (Anti-hCD20-hIgG1, kappa)

Isotype: Human IgG1NQ, kappa

Source: CHO cells

Formulation: 0.2 µm filtered solution in 68 mM sodium phosphate buffer (pH 7.4) with 91 mM glycine, 5% w/v saccharose, and stabilizing agents

Purity: Purified by affinity chromatography with protein G

Tested application: Flow cytometry and ADCC

Quality control:

• Binding of Anti-hCD20-hIgG1NQ to human CD20 has been tested using flow cytometry.
• The complete sequence of this antibody has been verified.
• The absence of bacterial contamination (e.g. lipoproteins and endotoxins) has been confirmed using HEK-Blue™ TLR2 and HEK-Blue™ TLR4 cells.

Contents

Anti-hCD20-hIgG1NQ purified monoclonal antibody is provided azide-free and lyophilized. It is available in two quantities:

• hcd20-mab12: 100 µg
• hcd20-mab12-03: 3 x 100 µg

Product is shipped at room temperature.

Store lyophilized antibody at -20°C.