[70]

Three Dimensional Growth of Human Retinal Progenitors: Rotary Cultures vs Bioreactor. K. Dutt and Y. Cao.  Department of Pathology, Morehouse School of Medicine, Atlanta, GA.

   Neural tissue damage in diseases like retinitis Pigmentosa (RP), age-related macular degeneration (AMD) and Parkinson’s disease remain a major problem in the field of medicine.  Replacement of damaged tissue by healthy tissue is one strategy being explored.  The therapeutic potential of multi lineage stem cells for applications such as tissue engineering and gene therapy are enormous.  The multipotential adult human retinal stem cell lines established in our lab induced enhanced differentiation and allowed the formation of 3D structures with photoreceptor cell differentiation when grown in NASA bioreactor.  

   In this study, we tested the utility of rotating cultures initially described by Moscona and colleagues in the 1970s.  We report that nontransformed human retinal progenitors, grown alone or as a co-culture with RPE form 3D structures, but the cell types generated in rotating cultures might be different.  Retinal cells grown as rotary and bioreactor cultures were assessed on days 1-10 by cellular and biochemical techniques.  Immunohistochemistry and western blot analysis suggests that rotary cultures promote significant upregulation of Tyrosine hydroxylase, Thy 1.1, NSE, and N acetyl transferase proteins.  While down regulating photoreceptor markers-D4 receptors, rod bipolar marker-PKCα and cone cell marker-calbindin, we conclude that both NASA bioreactor and rotating cultures allow 3D assembly.  However, the cell types generated in both vessels might differ in their phenotypes.  The bioreactor enhances photoreceptor phenotype whereas the rotating culture seems to induce differentiation along the ganglionic and amacrine cell phenotype.

   We conclude that by selectively manipulating culture conditions, we might be able to generate specific neural cell types to be tested for therapeutic purposes. 

(Support by NASA: NCC 9-112.)