Making extracellular scaffolds

Adipose tissue (body fat) and cell levitation are two methods being explored to create extracellular matrices for growing cells in tissue culture.

In order to get cells to form more than an amorphous clump, they need some sort of scaffold on which to grow. This scaffold supplies not only structure, but also key nutrients. Once the cells reach their mature size and shape, they secrete enzymes that break down the framework.

Currently, most biological scaffolds are made from proteins secreted by cancerous mouse cells, substances not fit for use in humans.

Glauco Souza and his colleagues from the Texas M.D. Anderson Cancer Center and from Rice University have been levitating cells into the proper orientation. They used viral particles to deliver tiny bits of iron into human glioblastoma cells and then placed the cells in magnetic fields. By carefully controlling the fields, the scientists were able to make the cell colonies grow into desired shapes.

Meanwhile, Rice University professor Deepak Nagrath and his colleagues have developed a new scaffold derived from adipose tissue and called ‘Adipogel’. Ultimately, the researchers hope to be able to inject the Adipogel scaffold suffused with stem cells into human patients, where the cells can repair or replace injured tissue.

Adipogel forms a viscous droplet when isolated on a petri dish. After further processing, it can be used as a natural extracellular matrix to support new tissue growth.

Photo credit: N. Sharma

Both of these methods show great promise. On the one hand, fat is easily obtained and extremely safe for treatment purposes, especially if derived from the patient. On the other, magnetic fields can be used on any kinds of cells, assuming you can get the cells to first incorporate iron. It’ll be interesting to see which method, if either, ends up in wider usage.