Prostate Organoid Assay: A Matrix Gel Ring-based Ex Vivo Culture Technique to Study the Differentiation Capacity of Prostate Epithelial Cells

The prostate epithelium primarily comprises basal epithelial and luminal epithelial cells. A monolayer of basal cells forms the outer lining of the gland and supports luminal cell survival. Conversely, the luminal cells line the lumen and secrete prostate-specific proteins.

To study prostatic epithelial differentiation ex vivo, begin with a suspension of basal prostate epithelial cells. Mix the suspension with a chilled basement membrane matrix in the desired ratio. Pipet this mixture next to the base of the inner wall of a cell-repellant culture plate. Swirl the plate for the mixture to form a ring along the circumference of the well.

Incubate the plate to allow the matrix to solidify. Supplement the culture with a preferred media. The growth factors in the media support the proliferation of basal epithelial cells. Concurrently, the cell-repellent nature of the culture dish prevents any cell attachment, encouraging the cells to form 3D spheroids within the matrix.

Over time, the spheroids develop lumens bordered with multi-layered epithelium. The lumen-lining basal epithelial cells eventually differentiate and form secretory luminal cells, giving rise to 3D glandular structures.