Organoïden

Organoïden are three-dimensional, self-organizing structures derived from stem cells that recapitulate key structural and functional aspects of actual organs. In vitro they are grown in a defined extracellular matrix and exposed to combinations of growth factors that steer development-like processes, enabling cells to differentiate into multiple lineages and to form organized, layer-like tissues.

Organoïden can be generated from pluripotent stem cells (embryonic or induced) or from resident adult progenitor cells. They have been established for several organ types, including brain, intestine, liver, kidney, pancreas and lung, among others. Patient-derived organoids can reflect the genetic makeup and disease features of an individual and are used to study disease mechanisms, test drug responses, and screen therapeutic compounds.

The standard workflow involves embedding cells in an extracellular matrix such as Matrigel, providing a defined sequence of signaling cues, and allowing self-organization to occur over weeks. Techniques such as genetic modification, single-cell profiling and imaging are used to characterize organoid structure and function. Some models integrate microfluidic or bioreactor systems to improve nutrient supply and sensor readouts; organoids may also be used to model host–microbe interactions by exposing luminal surfaces to microbes.

While organoïden offer valuable insights, they have limitations. They often lack a functional vasculature and immune components, show maturation differences from adult tissue, and exhibit batch-to-batch variability. Ethical, regulatory and quality-control considerations apply, particularly for patient-derived lines and potential therapeutic applications.

In outlook, organoïden are important research tools that complement animal models and traditional cell cultures. Progress aims to improve vascularization, immune integration, and standardization to broaden their translational potential, while recognizing that they are not yet equivalents of whole organs for transplantation.