Refining endometrial assembloids: a novel approach to 3-dimensional culture of the endometrium

Enhancing the efficacy of three-dimensional endometrial assembloid models is pivotal for deepening our comprehension of endometrial physiology. We investigated the optimal ratio of organoids to stromal cells in these models, utilizing human endometrial biopsies. Morphological and viability analyses revealed that the 1:1 and 1:2 ratios were optimal until day 4, after which viability declined significantly by day 10, coinciding with a notable disappearance of stromal cells. To overcome this challenge, we developed a hanging-drop culture model, which enhanced cell survival and better replicated natural cellular organization. These findings underscore the significance of considering stromal cell dynamics in refining assembloid models for studying endometrial physiology and endometrial-related pathologies.