[Morphologic differentiation of neuroblastoma cells induced by dimethyl sulfoxide]

Morphological features of neuroblastoma cells cultured in the presence of 1.0% dimethyl sulfoxide (DMSO) were investigated. The induced differentiation was characterized by appearance of long axon-like processes (neurites), cell size enlargement and inhibition of cell growth. Quantitative criteria for cell differentiation depending on survival time in the modified medium were estimated. The increase of total length of neurites was linear with time, the rate of their extension being 20.0 +/- 3 micron/h. The area of differentiated cell soma is 6-7 times higher than that of control cells. Increase of the DMSO concentration to 2.0% did not intensify neurite growth and enlargement of cell size but suppressed mitosis. Morphological criteria of cell differentiation are compared with probable functional changes in these cells.