3D cultures for human pluripotent stem cell -derived neuronal cells

M. Pajunen, T. Joki, L. Ylä-Outinen, M. Varjola, H. Skottman, and S. Narkilahti, abstract presented at 11th Annual Meeting of International Society for Stem Cell Research, June 12-15, 2013, Boston, MA, USA.

Background. Neurodegenerative disorders like Parkinson’s and Alzheimer’s diseases are associated with permanent damages to cells and brain structures. Encouragingly, there have been some success with neural transplants, however, the cell survival after grafting is still a major challenge. To improve the survival, the cells should be incorporated into protective biomaterials. These biomaterials should be non-toxic, three dimensional, support the cell viability and allow nutrition flux. In addition to the protection of the cells, biomaterials offer a more natural, tissue-like environment for the cells to grow in. For neural applications hydrogels are considered to be the best option. Here, we have tested the feasibility of the commercially available hydrogel PuraMatrix TM as an in vivo growth platform for human pluripotent stem cell -derived neural cells.

Methods. Human pluripotent stem cell -derived neural cells were seeded to different hydrogel concentrations on top of the gelled material, inside the hydrogel, or under the hydrogel. The cells were characterized using viability analysis, immunocytochemical staining, time-lapse monitoring, and confocal imaging. In addition, the maturation and electrical activity of the neuronal networks inside the hydrogel were characterized using microelectrode array. Results. The hydrogel was non-cytotoxic and supported the survival of neural cells, both neurons and glial cells. Moreover, neurons inside the gel developed more branched neurite structures compared to the traditional 2D culture. Importantly, these neurons were also able to form spontaneously functional networks.

Conclusions. Even though there are some challenges related to this material, like the drastic pH changes during gelation, our data encourages to further study this material for a growth matrix for human-derived neural cells. Also, further studies of neuronal functionality in 3D matrices are conducted.