Alginate as a new biomaterial for the growth of porcine retinal pigment epithelium.
OBJECTIVE
Determine the effect of a 3-dimensional alginate matrix on the growth and differentiation of cells isolated from porcine retinal pigment epithelium (RPE).


METHODS
Porcine RPE cells were harvested from enucleated eyecups, isolated by differential gravity sedimentation and cultured in either alginate alone (Group 1) or on plastic tissue culture plates followed by alginate (Group 2). Group 1 cells were cultured in alginate to evaluate the efficacy of the matrix as a culture medium. Group 2 cells were initially cultured on plastic to induce dedifferentiation. The cells were then harvested, suspended in alginate beads, and incubated for a second culture period to determine if the induced dedifferentiation was reversible.


RESULTS
The number of Group 1 cells was significantly greater (P < or = 0.01) at the end of the culture period. The amount of pigment and cell morphology of Group 1 cells at the end of the culture period was similar to that seen at initial cell isolation. The initial culture of Group 2 cells on plastic showed characteristic features of dedifferentiation marked by the loss of pigment and alterations in microscopic appearance. Secondary culture of dedifferentiated Group 2 cells in alginate beads resulted in a return to pigmentation and characteristic morphology for a majority of the cultured cells.


CONCLUSIONS
Porcine RPE cells can be propagated in alginate culture with a significant increase in cell numbers while maintaining normal morphology. Under the conditions described in the present study, the dedifferentiation of porcine RPE induced by standard in vitro culture methods is reversible.
Eurell
Thomas E
TE
Department of Veterinary Biosciences, College of Veterinary Medicine, University of Illinois, Urbana, IL, USA. teurell@uiuc.edu
Brown
Daniel R
DR
Gerding
Paul A
PA
Hamor
Ralph E
RE
D000464:Alginates / Q000494:pharmacology*; D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology*; D046508:Culture Techniques / Q000662:veterinary*; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D010857:Pigment Epithelium of Eye / Q000187:drug effects*; D013552:Swine
D000464:Alginates; D001672:Biocompatible Materials; D006603:Hexuronic Acids; D020723:Glucuronic Acid