Generation of Human Endometrial Assembloids with a Luminal Epithelium using Air–Liquid Interface Culture Methods

Abstract

The endometrial lining of the uterus is essential for women's reproductive health and consists of several different types of epithelial and stromal cells. Although models such as gland‐like structures (GLSs) and endometrial assembloids (EnAos) are successfully established, they lack an intact luminal epithelium, which makes it difficult to recapitulate endometrial receptivity. Here, a novel EnAo model (ALI‐EnAo) is developed by combining endometrial epithelial cells (EnECs) and stromal cells (EnSCs) and using an improved matrix and air–liquid interface (ALI) culture method. ALI‐EnAos exhibit intact EnSCs and glandular and luminal epithelia, which recapitulates human endometrium anatomy, cell composition, hormone‐induced menstrual cycle changes, gene expression profiles, and dynamic ciliogenesis. The model suggests that EnSCs, together with the extracellular matrix and ALI culture conditions, contribute to EnAo phenotypes and characteristics reflective of the endometrial menstrual cycle. This enables to transcriptionally define endometrial cell subpopulations. It anticipates that ALI‐EnAos will facilitate studies on embryo implantation, and endometrial growth, differentiation, and disease.

Restoration of functional endometrium in an intrauterine adhesion rat model with endometrial stromal cells transplantation

“…Single-cell sequencing of full-thickness normal human endometrium uterine from proliferative and secretory phases revealed four populations of stromal cells, secretory stroma (SCGB1D2), SFRP4 + stroma (SFRP4), DCN + stroma (DCN) and inflammatory stroma (IL6) [ 30 ]. In our reported human endometrial assembloids with a luminal epithelium, EnSCs were identified into six endometrial stromal cells populations, of which the EnSC subpopulation 2 (EsS2) is positive of CXCL8, CXCL1 and IL6 genes and exhibits immunoregulatory properties [ 53 ]. These studies suggest that immunoregulation of stromal cells may be exerted by some specific stromal cell subpopulations, and different stromal cell subpopulations are likely to play different roles in endometrial regeneration.…”

Basic Research Advances in China on Embryo Implantation, Placentation, and Parturition

“…Although models such as gland-like structures and endometrial assembloids have been successfully established, 114,115 the lack of intact luminal epithelium makes it difficult to recapitulate endometrial receptivity. Using an improved matrix and air-liquid interface culture method, Tian et al 116 developed a novel ALI-EnAo model composed of endometrial epithelial cells and stromal cells. ALI-EnAos recapitulated endometrial anatomy, cell composition, gene expression profiles, and hormone-induced menstrual cycle changes in vitro.…”

Bioengineering approaches for the endometrial research and application

“…In recent years, efforts have been made to develop platforms aimed at rebuilding or simulating the endometrial tissue, including two-dimensional (2D) cell culture systems and explant models to illustrate the histological and molecular characteristics of the endometrium [ [6] , [7] , [8] ]. Additionally, developing more dynamic and adjustable methods based on bioengineering technologies by taking advantage of replicating tissue structures and functions is essential to narrowing physiological gaps between tissues or organs in vivo and culture models in vitro [ 9 ].…”