In vitro neural injury model for optimization of tissue-engineered constructs.
Stem cell transplantation is a promising approach for the treatment of traumatic brain injury, although the therapeutic benefits are limited by a high degree of donor cell death. Tissue engineering is a strategy to improve donor cell survival by providing structural and adhesive support. However, optimization prior to clinical implementation requires expensive and time-consuming in vivo studies. Accordingly, we have developed a three-dimensional (3-D) in vitro model of the injured host-transplant interface that can be used as a test bed for high-throughput evaluation of tissue-engineered strategies. The neuronal-astrocytic cocultures in 3-D were subjected to mechanical loading (inducing cell death and specific astrogliotic alterations) or to treatment with transforming growth factor-beta1 (TGF-beta1), inducing astrogliosis without affecting viability. Neural stem cells (NSCs) were then delivered to the cocultures. A sharp increase in the number of TUNEL(+) donor cells was observed in the injured cocultures compared to that in the TGF-beta1-treated and control cocultures, suggesting that factors related to mechanical injury, but not strictly astrogliosis, were detrimental to donor cell survival. We then utilized the mechanically injured cocultures to evaluate a methylcellulose-laminin (MC-LN) scaffold designed to reduce apoptosis. When NSCs were co-delivered with MC alone or MC-LN to the injured cocultures, the number of caspase(+) donor cells significantly decreased compared to that with vehicle delivery (medium). Collectively, these results demonstrate the utility of an in vitro model as a pre-animal test bed and support further investigation of a tissue-engineering approach for chaperoned NSC delivery targeted to improve donor cell survival in neural transplantation.
Cullen
D Kacy
DK
Wallace H. Coulter Department of Biomedical Engineering, Institute for Bioengineering and Bioscience, Laboratory for Neuroengineering, Georgia Institute of Technology/Emory University, 313 Ferst Drive, Atlanta, GA 30332, USA.
Stabenfeldt
Sarah E
SE
Simon
Crystal M
CM
Tate
Ciara C
CC
LaPlaca
Michelle C
MC
D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000502:physiology; D001253:Astrocytes / Q000187:drug effects / Q000502:physiology; D016923:Cell Death / Q000502:physiology; D002470:Cell Survival / Q000187:drug effects / Q000502:physiology*; D002478:Cells, Cultured; D018920:Coculture Techniques / Q000379:methods; D004195:Disease Models, Animal; D005260:Female; D006085:Graft Survival / Q000187:drug effects / Q000502:physiology*; D020287:In Situ Nick-End Labeling; D007797:Laminin / Q000627:therapeutic use; D008747:Methylcellulose / Q000627:therapeutic use; D009474:Neurons / Q000187:drug effects / Q000502:physiology; D009924:Organ Culture Techniques / Q000379:methods; D051381:Rats; D033581:Stem Cell Transplantation / Q000379:methods*; D013234:Stem Cells / Q000187:drug effects / Q000502:physiology*; D013314:Stress, Mechanical; D023822:Tissue Engineering / Q000379:methods*; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology
D007797:Laminin; D053773:Transforming Growth Factor beta1; D008747:Methylcellulose