Neurons behaviour in presence of biomaterials

Oligodendrocytes (OD) were isolated from brain of rats or humans by Percoll gradient and seeded on plates coated with a basement membrane like extracellular matrix (ECM) prepared from bovine cornea1 endothelial cells. 80%-90% of the cells were identified as OD by indirect immuiofluorescence (IF) using rabbit anti-galactocerebroside serum (GalC). Starting from day 3 after plating, the ECM-cells expand cytoplasmatic processes and after one week the ECM-coated dish is ItJaded with cells creating a network which is mostly elaborated by GalC positive cells. The cells express cyclic nucleotide phosphohydrolase (CNP) activity which increase witlh time and network formation. At day 3-4 the cells were given a si using GalC combine 4 g gle pulse of labe'led thymidine(3H-T) for 24-32 hours, and IF with H-T autoradiograplhy revealed that 50-70% of the GalC positive cells incorporate H-T in their nuclei. Ce'lls can be splitted from culture by trypsin and EDTA treatment, and transfered to new ECM-coated plates; they reexpand GalC positive processes at a quicker -rate of growth, esipecially when serum free medium is used. Myelin lamellae were demonstrated on ECM-cultured rat OD preocesses by electron microscope. Chemical and enzymatic modifications of ECM suggest that laminin in conjunction with other ECM constituents is important for the proliferation and/or differentiation of mature OD.