organoides

Organoides, or organoids, are three-dimensional cell cultures that recapitulate aspects of real organs. They are usually derived from adult stem cells or pluripotent stem cells, such as induced pluripotent stem cells (iPSCs) or embryonic stem cells, and grown within a supportive three-dimensional extracellular matrix. Through self-organization guided by organ-specific signaling cues, these cells form miniature, organ-like structures that include multiple cell types and, in some cases, lumen formation. The field traces back to intestinal organoids described by Hans Clevers and colleagues in 2009, which demonstrated long-term expansion of self-organizing structures from adult stem cells.

Organoides can model a range of tissues, including the intestine, brain, liver, pancreas, kidney, lung, stomach, and retina. They often exhibit genetic and functional features of the corresponding organs, such as enzyme activity, barrier function, neural activity, or photoreceptor development. However, they are simplified versions of organs and typically lack full vascularization and immune components, which limits their maturation and long-term function. Variability between lines and differentiation protocols also poses challenges for reproducibility.

Applications of organoides are broad. They are used for disease modeling and understanding developmental processes, for drug screening and toxicity testing, and for personalized medicine approaches using patient-derived cells. In regenerative medicine, organoides offer potential avenues for transplantation and tissue replacement, though clinical translation remains experimental and subject to ethical and regulatory considerations.