Fluorescence Super-Resolution Imaging Chip for Gene Silencing Exosomes

Area of Science:

• Biomedical Engineering
• Molecular Biology
• Cancer Research

Background:

• Tumor-derived extracellular vesicles are emerging cancer biomarkers.
• Programmed Death-Ligand 1 (PD-L1) is a key immune checkpoint target for cancer immunotherapy.
• PD-L1 small interfering RNA (siRNA) offers advantages over monoclonal antibodies for gene silencing.

Purpose of the Study:

• To develop and validate an integrated microfluidic chip for investigating PD-L1 siRNA gene silencing.
• To quantitatively analyze PD-L1 expression on exosomes using advanced imaging techniques.
• To establish a novel platform for studying PD-L1 in tumor immunotherapy.

Main Methods:

• Culturing cells with PD-L1 siRNA within a microfluidic chip.
• Detecting secreted exosomes using super-resolution imaging.
• Employing a sandwich immunoassay and DNA-PAINT for quantitative PD-L1 analysis on exosomes.

Main Results:

• Successful gene silencing of PD-L1 by siRNA was validated.
• High-resolution quantitative analysis of PD-L1 on exosomes was achieved using DNA-PAINT.
• The integrated microfluidic chip demonstrated simplified workflow and enhanced detection precision.

Conclusions:

• The developed microfluidic chip combined with DNA-PAINT offers a powerful integrated platform for PD-L1 research.
• This approach facilitates the study of PD-L1-related tumor immunotherapy.
• The platform enables precise structural and content analysis of exosomes for biomarker discovery.