Microdissection tools to generate organoids for modeling the tumor immune microenvironment

Area of Science:

• Biotechnology
• Cancer Research
• Immunology

Background:

• Patient-derived tumor organoids are valuable for personalized cancer therapy but often lack essential immune components.
• Maintaining native tumor-immune cell interactions is critical for effective cancer immunotherapy testing.
• Current manual methods for preparing tumor fragments are slow and inconsistent.

Purpose of the Study:

• To develop and evaluate novel microdissection devices for generating intact tumor fragments.
• To create air-liquid interface (ALI) organoids that preserve endogenous immune cells within tumor fragments.
• To assess the impact of organoid size and dissection method on immune cell viability and immunotherapy response.

Main Methods:

• Introduction of two microdissection devices: the µDicer (silicon microblades) and the µGrater (stainless steel array).
• Generation of ALI organoids from mouse B16 melanoma using fragments prepared by µDicer, µGrater, and manual mincing.
• Analysis of immune cell viability, composition, and response to anti-PD-1 immunotherapy in generated ALI organoids.

Main Results:

• The µDicer allowed investigation of organoid size effects, showing immune cell viability is maintained for sizes > ~400 µm.
• The µGrater accelerated tumor fragment dissection by 4.5 times compared to manual mincing.
• ALI organoids generated using the µGrater exhibited comparable immune cell profiles and anti-PD-1 response to manually minced samples.

Conclusions:

• Microdissection devices like µDicer and µGrater effectively generate tumor fragments for ALI organoids preserving native tumor-immune interactions.
• The µGrater offers a faster and reproducible alternative to manual mincing for preparing tumor organoids.
• These advancements support the development of more accurate preclinical models for personalized cancer immunotherapy.