Historical evolution of spheroids and organoids, and possibilities of
use in life sciences and medicine
Abstract
An impressive percentage of biomedical knowledge and advances were
achieved through animal research and cell culture investigations. For
drug testing and disease researches, both animal models and preclinical
trials with cell cultures are extremely important, but they present some
limitations, such as ethical concern and lack of representatively of
human tissues and organs. Most cells are currently cultured using
two-dimensional (2D) methods, but new and improved methods that
implement three-dimensional (3D) cell culture techniques suggest
convincing evidence that much more advanced experiments can be performed
with more complex information. The environment and cell types in 3D
culture can be manipulated to mimic tissue in vivo and provide more
accurate data on cell-to-cell interactions; the cultivation techniques
are based on a scaffold, which can be based on hydrogel or polymeric
material, in addition there are techniques without using scaffold, such
as suspended microplates, magnetic levitation and microplates for
spheroids with ultra-low fixation coating. Even though 3D culturing is
clearly incapable of replacing other current research types, they might
continue to replace some unnecessary animal experimentation, as well as
improve monolayer cultures. It is not even recommended or expected that
3D models substitute all other research types, but in regard to animal
testing, they come in hand for the 3 Rs: Reduction, Refinement,
Replacement. In this aspect, 3D culture emerges as valuable alternatives
to the investigation of functional, biochemical and molecular aspects of
human pathologies.