Building consensus on definition and nomenclature of hepatic, pancreatic, and biliary organoids

Abstract

Hepatic, pancreatic, and biliary (HPB) organoids are powerful tools for studying development, disease, and regeneration. As organoid research expands, the need for clear definitions and nomenclature describing these systems also grows. To facilitate scientific communication and consistent interpretation, we revisit the concept of an organoid and introduce an intuitive classification system and nomenclature for describing these 3D structures through the consensus of experts in the field. To promote the standardization and validation of HPB organoids, we propose guidelines for establishing, characterizing, and benchmarking future systems. Finally, we address some of the major challenges to the clinical application of organoids.

Keywords: Delphi method; HPB; bile duct; epithelial organoid; gallbladder; liver; multi-organ organoid; multi-tissue organoid; pancreas; tumor organoid.

Figure 1.. Overarching definition of an organoid (top panel) along with the three sub-classifications (bottom 3 panels)

Figure 2.. Self-renewal of organoids

Upon physical or enzymatic and/or chemical dissociation of organoids into fragments or single cells (followed by secondary culture in expanding conditions), cells reorganize and expand, reforming organoids.

Figure 3.. Generation of epithelial, multi-tissue, and multi-organ organoids from iPSCs

Figure 4.. Nomenclature for epithelial organoids derived from primary tissue of the adult liver, pancreas, and biliary tree

Figure 5.. Nomenclature for tumor organoids derived from primary or metastatic tumors of the liver, pancreas, and biliary tree

Figure 6.. Guidelines for the establishment of novel organoid systems

Dotted boxes represent facultative steps.