Human Neuroblastoma, Strain Sk-N-Sh, as a Model System of Nerve Cell Differentiation: Neuronal Development, Plasminogen Activator Release, and Unscheduled Deoxyribonucleic Acid Synthesis

212 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1981.This study characterized morphological and biochemical properties of the cultured human neuroblastoma, strain SK-N-SH, maintained in vitro. In complete growth medium supplemented with 15% fetal bovine serum, SK-N-SH cells exhibited a large nucleus, with several distinct nucleoli, and neurite- and dendrite-like processes with branched end terminals. Within a few hours after subcultivation, the morphological complexity of the cells increased as evidenced by a greater number of cells with neurite processes longer than 50 (mu)m, and an increased elongation of the processes already present. Two to six percent of the cells had at least one process greater than 50 (mu)m in length on day 1 after plating, and this increased to fifteen to thirty-five percent on days 3 or 4. The mean total summed process length per cell increased (TURN)4.7-fold between days 1 and 2.The SK-N-SH cultures released progressively increasing levels of plasminogen activator activity on a per dish basis, beginning in the late-exponential phase (11 days) and extending into the post-exponential phase (23 days). However, the amount of plasminogen activator released per cell was constant during this time period.In order to determine if deoxyribonucleic acid (DNA) repair capability decreased with maturation of the cultures, unscheduled DNA synthesis (UDS) induced by ultraviolet light (UVL) was measured during the period of development of morphological complexity. With increasing morphological complexity up to day 10, the level of repair capability did not decline.The addition of 1 mM dibutyryl-adenosine 3':5'-cyclic monophosphoric acid (dibutyryl-cyclic-AMP) to the growth medium increased both the proportion of SK-N-SH cells with at least one process greater than 50 (mu)m in length (e.g., approximately 2-fold after 3 days of exposure) and the release of plasminogen activator activity (e.g., a maximum of 3.8-fold on a per cell basis after 3 days of exposure). Two and a half days of treatment with 1 mM dibutyryl-cyclic-AMP did not modify the level of UVL-induced UDS in SK-N-SH cells. In addition, a preliminary study indicated that 4 1/2 days of exposure to 1 (mu)g/ml (beta)-nerve growth factor ((beta)-NGF) resulted in an increased sprouting of processes from cells, but also had no effect on repair synthesis capability. Therefore the UDS data from developing cultures at various times after plating, and from cultures treated either with dibutyryl-cyclic-AMP or (beta)-NGF, did not support the view that DNA repair capability declined as a consequence of increased morphological complexity in cultured SK-N-SH cells.The release of plasminogen activator activity by SK-N-SH cells was examined after exposure to a variety of agents (e.g., dibutyryl-cyclic-AMP, hydroxyurea, and UVL). Since it had been reported that plasminogen activator activity was correlated with tissue remodeling in other cases, this study included a discussion of the relationship between plasminogen activator release and neuronal development.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD