Individual Stem Cell Spheroid

Finally, we get to the star behind the website. A stem cell spheroid, otherwise known as an aggregate of stem cells condense into a spherical shape. This structure has been motivated by embryonic development, as our bodies form as cellular aggregates (embryos). It is very apparent in the literature that direct cell to cell contact is essential to drive organ development and proper function. When stem cells are placed in direct contact in this manner, they divide faster, secrete a potent cocktail of angiogenic factors (help blood vessels form), turn into cartilage cells more efficiently (differentiate into chondrocytes), and even can be fused to create macroscopic tissues. There is one downside to spheroids, which is nutrient diffusion. As these aggregates form thousands of connections, it becomes very hard for nutrients to diffuse into the core of the spheroid, where cells are most likely to die due to this phenomena.