Antibody Internalization

Accelerate Your Antibody-Drug Conjugate (ADC) Discovery with nanobody Technology

Antibody-drug conjugates (ADCs) represent a leading class of targeted cancer therapies. The efficacy of an ADC relies heavily on the internalization of the antibody to release the cytotoxic payload specifically within tumor cells. Traditional screening for internalization candidates is often slow, expensive, and technically challenging.

Echo Bio offers a revolutionary suite of Nanobody-based tools designed to simplify, accelerate, and reduce the cost of antibody internalization assays and ADC pre-screening

• ADC-VHH Cytotoxicity screener

Rapid, Cost-Effective Pre-Screening for Cytotoxicity

The ADC Cytotoxicity Screener is a secondary antibody-drug conjugate that uses a high-affinity nanobody (VHH) linked to potent toxins (MMAE, MMAF, DXD, or PBD). It binds specifically to the Fc or Kappa region of your primary monoclonal antibody, instantly converting it into a pseudo-ADC for cell-based killing assays

Key Advantages:

• High Stability: Nanomolar (nM) affinity ensures stable formation of the Antibody-Toxin complex.
• Minimal Interference: The small size (approx. 160kD complex) mimics real ADCs and minimizes steric hindrance during internalization.
• Species Specificity: Available for Human and Mouse IgG primary antibodies.
• Versatile Payloads: Available with MMAE, MMAF, DXD (Deruxtecan analog), and PBD payloads

Case Study

The data below demonstrate the cytotoxic profile of Herceptin (Trastuzumab) on SKBR3 cells. Herceptin alone does not kill the cells in this assay. However, when combined with the Anti-Human IgG Nano-Secondary ADC (VcMMAE), it demonstrates potent cell killing capabilities.

• Nano-DT (Next-Gen Internalization Detection)

Superior Sensitivity Over DT-3C

Traditional DT-3C reagents use Protein G to bind antibodies, which often results in non-specific binding to bovine IgG in serum, causing high background noise. VHH-DT replaces Protein G with a high-affinity Nanobody that does not bind bovine IgG, offering a cleaner, more sensitive signal

Key Advantages:

• Zero Serum Interference: Does not bind to bovine IgG.
• Simple Workflow: Mix and incubate for 10–15 minutes at room temperature.
• High Throughput: Compatible with MTT, WST-1, and CTG assays.

Case Study

• Dual Payload ADC System

Precision Assembly for Dual-Toxin Delivery

Leveraging the specificity of nanobodies, we enable the construction of Dual-Toxin Payload ADCs. By targeting different constant regions of the same human IgG (e.g., the Fc region and the Kappa light chain), two different toxins can be delivered simultaneously.

Toxins available: MMAE, MMAF, DXD, and PBD; Or customers provided

• VHH-pH-Sensitive Probes

Wash-Free Endocytosis Detection

These probes consist of nanobodies coupled to pH-dependent fluorescent dyes. These dyes are non-fluorescent at neutral pH (outside the cell) but fluoresce brightly upon internalization into the acidic environment of endosomes and lysosomes. Applicable to a variety of detection systems: fluorescence imaging systems, high-content analysis, flow cytometry.

• Mechanism: Binding -> Internalization -> Acidification -> Fluorescence.
• Speed: Labeled antibodies ready in 10 minutes.
• Colors: Available in Red (pH-Red 600) and Deep Red (Deep Red 630).

Your Partner in VHH-Based Therapy Development Specializing in high-performance alpaca nanobodies and recombinant reagents.