Monoclonal scFv antibody against human CD19 and human CD3

Anti-hCD19-CD3 is a bispecific antibody that recognizes two human cell markers: hCD19, which is expressed on the surface of B cells, and hCD3 which is part of the T cell receptor. This antibody features Blinatumomab single-chain variable fragments (scFv) joined by a glycine-serine linker. These two scFvs have been cloned from the anti-hCD19 (clone HD37) and anti-hCD3 (clone L2K-07) monoclonal antibodies [1,2]. Blinatumomab is used for the treatment of refractory acute lymphocytic leukemia (ALL) in clinics. By binding to hCD3 and hCD19, Blinatumomab engages unstimulated T cells to proliferate and exert cytotoxic activity on CD19-positive lymphoma cells [2]. Blinatumomab does not cross‑react with CD3 and CD19 from mice, rats, or dogs [3].

Anti-hCD19-CD3 bispecific antibody can be used for fine-tuning studies of B cell contact-dependent killing and T cell activation/proliferation.

Negative control antibodies are also available from InvivoGen: Anti-hCD19-βGal and Anti-βGal-hCD3.

References:

1. Krishnamurthy A. & Jimeno A., 2017. Bispecific antibodies for cancer therapy: A review. Pharmacol Ther. S0163-7258(17)30293-0.2. Bargou R. et al., 2008. Tumor Regression in Cancer Patients by Very Low Doses of a T Cell– Engaging Antibody. Science. 321(5891):974-7. 3. Trivedi A. et al., 2017. Clinical Pharmacology and Translational Aspects of Bispecific Antibodies. Clin Transl Sci. 10(3):147-162.

Figures

Jurkat-Lucia™ NFAT cell activation upon incubation with Raji B cells and Anti-hCD19-CD3.

(A) Raji cells were pre-incubated with Anti-hCD19-CD3, or the two bispecific negative controls Anti-β-Gal-hCD3 and Anti-hCD19-β-Gal for 30 minutes before addition of Jurkat-Lucia™ NFAT cells. After 8 hours incubation, T cell activation was determined by measuring the Lucia luciferase activity using QUANTI-Luc™ detection reagent. Results are presented as relative activity expressed as a percentage of Lucia activity in samples with the highest dose of antibody.(B) Target specificity of Anti-hCD19-CD3 was verified upon incubation with Jurkat-Lucia™ NFAT cells and Raji cells as described in (A), with Jurkat-Lucia™ NFAT cells only, or with Raji cells only. T cell activation was determined by measuring the Lucia luciferase activity using QUANTI-Luc™ and expressed as relative light units (RLUs).

Specifications

Clonality: Monoclonal antibody.

Specificity: Targets cells expressing human CD19 and human CD3.

Isotype: none (scFv).

Source: CHO (Chinese hamster ovary) cells.

Purity: > 90% Purified by affinity chromatography.

Quality control:

•    Binding to hCD19 and to hCD3 has been confirmed by flow cytometry.
•    Biological activity has been confirmed using cellular assays.
•    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

10 µg Anti-hCD19-CD3, purified antibody, provided azide-free and lyophilized.

Product is shipped at room temperature.

Store lyophilized antibody at -20°C.

Lyophilized product is stable for at least 1 year.