Imaging mass spectrometry for the precise design of antibody-drug conjugates

Area of Science:

• Oncology
• Immunotherapy
• Analytical Chemistry

Background:

• Antibody-drug conjugates (ADCs) are advanced immunotherapeutics for targeted cancer treatment.
• Tissue factor (TF) is highly expressed in various cancers and tumor vasculature, making it a viable therapeutic target.
• Designing effective ADCs is challenging due to their complex structures and the need for precise drug delivery.

Purpose of the Study:

• To develop and evaluate antibody-drug conjugates (ADCs) targeting human tissue factor (TF) for cancer therapy.
• To assess the efficiency and selectivity of ADC-mediated anticancer agent (ACA) release and distribution within tumor tissues.
• To explore the utility of matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) in evaluating ADC performance.

Main Methods:

• Preparation of TF-specific ADCs comprising a monoclonal antibody (mAb) linked to monomethyl auristatin E (MMAE) via a valine-citrulline (Val-Cit) linker.
• Utilizing matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) for direct detection and mapping of molecular distributions.
• Analyzing the intratumoral distribution of the released anticancer agent (MMAE) from the ADC within tumor tissues.

Main Results:

• Successful preparation of a human TF ADC designed for targeted cancer therapy.
• MALDI-IMS demonstrated the capability to directly visualize the intratumoral distribution of the released MMAE.
• The study confirmed the feasibility of using MALDI-IMS to track ACA distribution from ADCs in situ.

Conclusions:

• MALDI-IMS is a valuable tool for assessing the efficacy and distribution of ADCs within tumor microenvironments.
• This technique facilitates the direct evaluation of ADC drug release and distribution, aiding in the optimization of ADC design.
• The findings support the advancement of TF-targeted ADCs and the application of advanced imaging techniques in drug development.