Abstract
Abstract: :
Purpose: Tissue engineering is the reconstruction of three–dimensional (3–D) masses in vitro. The self–assembly of cells in culture to form multicellular spheroids was initially shown by tumor and embryonic cells. Spheroid formation by normal adult cells required the use semi–adhesive substrata. To achieve higher order structures scientists started to rely heavily on scaffolds. However, no scaffolds or substrata have been found that can simultaneously support various cellular phenotypes. Methods: Vascular retinal endothelial cells were plated on a substratum composed of various dilutions of bovine vitreous with or without various growth factors. 3–D structures were studied histochemically. Results: By seeding bovine retinal endothelial cells directly onto the bovine vitreous or dilutions of it, we were able to show that these cells move, invade, contact one another, form sheets, tubes, sprouts, and other 3–D structures. We were also able to show that cell behavior on the vitreous can be altered by the addition of growth factors. Conclusions: The vitreous exhibited powerful morphing capabilities by directing the formation of 3–D multicellular masses without the use of scaffolding. Furthermore, we also show that the vitreous can support the simultaneous growth and maintenance of different types of multicellular structures and cellular phenotypes. We hypothesize that it would be an ideal substratum for tissue engineering.
Keywords: vitreous • extracellular matrix • vascular cells