However, the number of published studies using the intestinal enteroid/organoid model to specifically identify drug targets for IBD treatment is usually thus far small
However, the number of published studies using the intestinal enteroid/organoid model to specifically identify drug targets for IBD treatment is usually thus far small. technology has allowed an exciting opportunity to study human IECs comprising all normal epithelial cells. This long-term epithelial culture model can be generated from endoscopic biopsies or surgical resections and recapitulates the tissue of origin, representing a promising platform for novel drug discovery in IBD. This review Rabbit Polyclonal to Integrin beta5 explains the advantages of intestinal enteroids/organoids as a research tool for intestinal diseases, introduces studies with these models in IBD, and gives a description of the current status of therapeutic approaches in IBD. Finally, we provide an overview of the current endeavors to identify a novel drug target for IBD therapy based on studies with human NSC632839 enteroids/organoids and describe the challenges in using enteroids/organoids as an IBD model. physiology, even after many generations, apparently with limited genetic or physiologic alterations. Additionally, intestinal enteroids/organoids can be easily established from endoscopic biopsies in IBD patients and maintain the location or some disease specific features[14,25-28]. Therefore, the intestinal enteroid/organoid culture system represents a promising tool for IBD modeling and drug development focusing on IEC dysfunction. However, the current limitation of this model is that it is not yet known if this model maintains the inflammatory phenotype and epigenetic stem cell modifications that occur in the IBDs. INTESTINAL ENTEROIDS/ORGANOIDS DERIVED FROM ADULT ISCS Human mini-intestines are NSC632839 derived either from adult ISCs (enteroids/ organoids)[23,29] or from induced pluripotent stem cells (iPSCs)(organoids). The iPSCs-derived intestinal organoids contain both epithelium and mesenchyme including myofibroblasts, easy muscle cells[29-31] but have limitations of NSC632839 requiring meticulous maintenance and initially mimicking fetal tissue. In contrast, the adult ISCs-derived intestinal enteroids/organoids can be easily established from human tissue (intestinal crypts), making it a tool more accessible to general researchers. Thus, this review specifically focuses on intestinal enteroids/organoids derived from an adult ISC origin. Intestinal enteroids/organoids can be generated from single Lgr5+ (Leucine-rich repeat-containing G protein-coupled receptor 5) ISC plus Paneth cells or from intestinal crypts made up of ISCs[21-23]. Intestinal crypts can be isolated from surgical resections or endoscopic biopsies, embedded in Matrigel (an extracellular matrix-containing material), and cultured as three-dimensional (3D) spheroids in several growth factors (Wnt3A, R-spondin, Noggin, and EGF) enriched media. After withdrawal of critical growth factors, intestinal enteroids/organoids differentiate to mimic IECs in villi composed of mature enterocytes, NSC632839 enteroendocrine cells, goblet cells, and tuft cells while ISCs and transit-amplifying cells are lost. THE ADVANTAGES OF INTESTINAL ENTEROIDS/ORGANOIDS AS A RESEARCH TOOL FOR INTESTINAL NSC632839 DISEASES Intestinal enteroid/organoid culture system can overcome the limitations of immortalized epithelial cell lines, human fetal intestinal organ cultures, and animal models. In contrast to cell lines which are genetically transformed and thus represent altered genotypes and phenotypes significantly different from those of primary cells, the intestinal enteroid/organoid culture is a primary culture system which maintains characteristics of human intestinal epithelium even after many passages. Furthermore, the current human cancer derived intestinal epithelial cell lines, as normally grown, consist of a single cell type (culture system, mechanistically similar to human diseases, and thus potentially more precisely predicting drug response in humans. In particular, growing enteroids as polarized monolayers instead of spheroids allows direct apical and basolateral access by pathogens and oral drugs, and subsequently enables the effective study of ion transport and secretory functions. A recent study demonstrated the successful use of enteroid monolayers in drug discovery by miniaturizing mouse colonoid monolayer cultures to 96-well plates, and conducting a phenotypic screen of approximately 2000 drug candidates. We have adopted the following approach for development of anti-diarrheal drugs. Identification of drug targets includes studies in diarrheal models in human enteroid monolayers. Initial drug candidates are screened early for toxicity in human enteroids with further development curtailed if human intestinal toxicity is usually identified. Once pharmacokinetic approaches are carried out in mouse intestine and human colon cancer cell lines, human enteroids are studied to determine IC50 and if comparable it is considered that the specific drug can be further developed. This approach was used with the CFTR inhibitor BPO-27 which is now under development by pharma for phase I and II studies. Human enteroids are amenable to lipofectamine-, low voltage electroporation-, and viral-based genetic manipulation including knock down, knock-out, knock-in, or overexpression. The CRISPR/Cas9 system was also used to edit the genome of intestinal enteroids derived from cystic fibrosis patients and repaired the cystic.