Aparna started with an overview of the historical development of cell culture models. Tissue Cultures in Petri Dishes (in 2D layers) was started off by Wilhelm Roux in 1885. The field has moved onto organotypic slice models where tissue slices were grown and more recently onto 3D cultures where 3D scaffolds (10-30 micrometers) are provided for the cells to grow.
Aparna cited a number of studies where 3D culture models with different types of scaffolds have been compared with the traditional 2D cell culture approaches. The 3D culture approach seems to be better for a number of reasons:
- Mimics cytoarchitecture of in-situ tissues
- Tuned to support differentiation and maturation
- Better gene expression and cellular behaviour
- Higher cell density for neurons (but no difference for astroglia)
- More robust survival - resistant to lack of adhesion or supplements - these are conditions of severe stress that are devastating for 2D cultures.
- Relative ease in studying cells that are difficult to study in 2D (such as primary motor neurons)
A number of 3D scaffolds are now commercially available - ranging from the natural Aragonite (bio-active, derived from the highly porous coral exoskeleton, made up of Calcium Carbonate and functions as a calcium supplement), Hydrogel (synthetic and used for neuronal cells), Human ECM (contains collagens, laminins etc) and PuraMatrix (considered to be self-assembling).
Given the number and range of benefits accrued, Aparna concluded that organotypic 3D cell culture models are valuable for the study of neurodegenerative diseases.