Abstract IA008: Modeling immune-epithelial interactions in health and disease using human intestinal enteroid co-cultures

Abstract

Abstract Human intestinal enteroids derived from Lgr5+ actively dividing adult stem cells offer a relevant ex vivo system to study biological processes of the human small intestine and colon. While these primary cultures recreate cellular and functional features of the intestinal epithelium of the small intestine (enteroids) or colon (colonoids), they are limited by the lack of associated cell types, including immunological cells, nerves, stromal cells that help maintain tissue homeostasis and respond to external challenges. In the gut, innate immune cells interact with the epithelium by conducting lumial surveillance, support barrier function, and deploy effector functions in response to injury/damage. We have established a co-culture system of enteroid/colonoid monolayers and underlying macrophages and polymorphonuclear neutrophils to recapitulate the cellular framework of the human intestinal epithelial niche. Human intestinal enteroids can generated from biopsies or resected tissue from any segment of the human intestine/colon and maintained in long-term cultures in a basement membrane-rich matrix supplemented with growth factor-conditioned media necessary to maintain intestinal stem cell homeostasis. Immune cells are isolated from fresh human whole blood or frozen peripheral blood mononuclear cells (PBMC) and co-cultured with human intestinal enteroids/colonoids grown as confluent monolayers on permeable supports (e.g., Transwells). This configuration allows for controlled access to the apical side of the epithelium to mimic the gut luminal environment as well as the basolateral side occupied by immune cells to mimic the mucosal environment. Enteroid-immune co-cultures enable multiple outcome measures, including transepithelial resistance, production of cytokines/chemokines, phenotypic analysis of immune cells, tissue immunofluorescence imaging, protein or mRNA expression, antigen or microbe uptake, and other cellular functions. Citation Format: Nicholas C. Zachos. Modeling immune-epithelial interactions in health and disease using human intestinal enteroid co-cultures [abstract]. In: Proceedings of the AACR Special Conference on Colorectal Cancer; 2022 Oct 1-4; Portland, OR. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_1):Abstract nr IA008.