Anti-TROP2 monoclonal antibody for ADC

Monoclonal human IgG1 antibody against TROP2 for antibody-drug conjugation

InvivoGen provides Anti-TROP2-hIgG1, a monoclonal antibody (mAb) specifically developed for the generation of antibody-drug conjugates (ADCs). This mAb features:

Anti-TROP2 PRR ligand bioconjugation
(click to enlarge)

• the variable region of sacituzumab, which specifically targets the human trophoblast cell-surface antigen 2 (TROP2),
• a human IgG1 constant region that displays high effector functions, including antibody-dependent cell-mediated cytotoxicity (ADCC), and complement-dependent cytotoxicity (CDC).

InvivoGen's Anti-TROP2-hIgG1 has been generated by recombinant DNA technology, produced in CHO cells, and purified by affinity chromatography.

TROP2 background

TROP2 (trophoblast cell-surface antigen 2), also known as TACD2 (tumor-associated calcium signal transducer 2), is a transmembrane protein expressed in normal human tissues, including breast, cervix, kidney, lung, and pancreas, and is upregulated in most tumors of epithelial origin [1]. TROP2 plays an important role in embryonic development and is implicated in several oncogenetic signaling pathways leading to proliferation [1].
One therapeutic strategy aiming at killing TROP2+ cancer cells, notably in triple-negative breast cancer patients, uses the FDA-approved antibody-drug conjugate (ADC) Trodelvy [2,3]. It consists of the combination of the Anti-TROP2 sacituzumab and the SN-38 cytotoxic payload [2,3]. This ADC allows targeted drug delivery to cancer cells in addition to the mAb-mediated effector functions [2,3]. Other TROP2-targeting ADCs featuring different cytotoxic cargos have been developed and have progressed to human clinical trials [4].

Anti-TROP2 ADC modes of action
(click to enlarge)

In a co-culture of TROP2+ tumor cells and human peripheral blood monocytes (PBMCs), ADCs combining InvivoGen's Anti-TROP2-hIgG1 and STING or TLR7 agonists induce a significantly higher production of IL-6 and CXCL10 pro-inflammatory cytokines than unconjugated agonists or negative control ADCs (see Figures).

Key features of Anti-TROP2-hIgG1:

• Clinically-relevant variable region targeting human TROP2 (sacituzumab)
• Human IgG1 constant region for high effector functions
• Functionally validated by flow cytometry and ADC-based cellular assays
• The absence of bacterial contamination has been confirmed

InvivoGen offers conjugatable PRR ligands for building immunostimulatory ADCs.
You may choose from TLR7 and STING agonists:
- Conjugatable TLR7 agonists: TL7-887 and TL7-975
- Conjugatable STING agonists: STG-982 and STG-968

Learn more about bioconjugation

InvivoGen’s products are for research use only, and not for clinical or veterinary use.

References

1. Trerotola, M., et al., 2013. Upregulation of Trop-2 quantitatively stimulates human cancer growth. Oncogene 32, 222–233.
2. Drago J.Z. et al., 2021. Unlocking the potential of antibody–drug conjugates for cancer therapy. Nat Rev Clin Oncol. 18-6):327.
3. Tarantino P. et al., 2022. Antibody-drug conjugates: smart chemotherapy delivery across tumor histologies. CA Cancer J Clin. 72:165-182.
4. Shaffer, C. 2021. Trop2 deal heats up antibody–drug conjugate space in cancer. Nat Biotechnol 39, 128–130.

Figures

Cell surface staining of HER2 using Anti-HER2-hIgG1 mAb. ~5 x 10⁵ BxPC-3 TROP2⁺ cells were incubated with 1 µg of Anti-TROP2-hIgG1 mAb or an isotype control for 45 min at 4°C. Cells were then washed and incubated with 250 ng of goat anti-human κ light chain antibody coupled to PE for 1h at 4°C. Cell surface staining was analyzed by flow cytometry.

ELISA detection of TROP2 using Anti-TROP2-hIgG1 mAb. TROP2-Fc fusion protein (1 μg/ml) was coated on ELISA plates overnight. A 3-fold serial dilution of Anti-TROP2-hIgG1 (red curve) or of Anti-βGal-hIgG1 control mAb (grey curve) was realized for the capture step. An HRP-labelled anti-human κ light chain antibody (1/1000 dilution) and the HRP substrate OPD (o-phenylenediamine dihydrochloride) were used for the detection step. Absorbance was read at 490 nm.

Dose-response of human PBMCs co-cultured with BxPC-3 tumor cells and Anti-TROP2/STG-982 or Anti-β-Gal/STG-982 ADC. 1.5x10⁵ human PBMCs and 5x10⁴ BxPC-3 TROP2⁺ tumor cells (A) or 1.5x10⁵ human PBMCs only (B) were incubated with increasing concentrations of Anti-TROP2/STG-982 ADC (DAR ~4), Anti-β-Gal/STG-982 ADC (DAR ~4), or STG-982 only. After overnight incubation, the STING-mediated response was assessed by measuring the production of CXCL10 in PBMC and BxPC-3 co-culture supernatants, using an ELISA. The optical density (OD) at 450 nm is shown.

Dose-response of human PBMCs co-cultured with BxPC-3 tumor cells and Anti-TROP2/TL7-887 ADC. 1.5x10⁵ human PBMCs and 5x10⁴ BxPC-3 tumor cells (A) or 1.5x10⁵ human PBMCs only (B) were incubated with increasing concentrations of Anti-TROP2/TL7-887 ADC (DAR ~6), Anti-β-Gal/TL7-887 ADC (DAR ~6), or TL7-887 only. After overnight incubation, the TLR7-mediated response was determined using HEK-Blue™ IL-6 reporter cells. Briefly, the levels of IL-6 production in PBMC and BxPC-3 co-culture supernatants were assessed by measuring the SEAP activity of HEK-Blue™ IL-6 reporter cells, using QUANTI‑Blue™, a SEAP detection reagent. The optical density (OD) at 630 nm is shown.

Specifications

Specificity: Targets cells expressing TROP2

Variable region biosimilar: Sacituzumab

Isotype: Human IgG1, Kappa

Source: Chinese hamster ovary (CHO) cells 

Formulation: 0.2 μm filtered solution in 150 mM sodium chloride, 20 mM sodium phosphate buffer with 5% saccharose

Purification: Affinity chromatography with protein A

Tested Applications: Flow cytometry, ELISA, Antibody-drug conjugation

Quality control:

• The binding of Anti-TROP2-hIgG1 mAb to TROP2 has been validated using flow cytometry, ELISA, and antibody-drug conjugate (ADC)-based cellular assays.
• The complete sequence of the antibody has been verified.
• The absence of bacterial contamination (e.g. lipoproteins and endotoxins) has been confirmed using HEK-Blue™ hTLR2 and HEK-Blue™ TLR4 cellular assays.

Contents

• 1 mg of purified Anti-TROP2-hIgG1 monoclonal antibody (mAb), provided azide-free and lyophilized

 The product is shipped at room temperature.

 Store lyophilized antibody at -20 °C.

 Lyophilized product is stable for at least 1 year. Reconstituted antibody is stable for 1 month at 4°C and for 1 year at -20°C. Avoid repeated freeze-thaw cycles.

Citations