Cochran M, Black M M
Brain Res. 1985 Jan;349(1-2):105-16. doi: 10.1016/0165-3806(85)90136-1.
We have investigated mouse and rat ganglionic Schwann cells as possible sources of neurite outgrowth-promoting factors by co-culturing Schwann cells with nerve growth factor (NGF)-responsive PC12 pheochromocytoma cells primed by pretreatment with NGF. NGF-primed PC12 cells are capable of neurite regeneration when provided with an appropriate neurite promoting factor such as NGF. When primed PC12 cells were co-cultured with Schwann cells in the absence of exogenous NGF, PC12 cells that directly contacted Schwann cells became enlarged and flattened, attaining a neuron-like morphology within one day. When contact with Schwann cells was established, PC12 cells regenerated neurites by the first day of co-culture and these were maintained throughout the experiments (7 weeks). Most PC12 cells cultured in the same collagen-coated dishes with Schwann cells, but not directly in contact with them, failed to regenerate neurites. Instead, they began to proliferate, forming cell clusters. Neurite regeneration by PC12 cells in contact with Schwann cells was not blocked by antibody to NGF. These results demonstrate the presence of a neurite-promoting activity localized to the vicinity of the Schwann cell surface which is capable of eliciting regeneration and long-term maintenance of PC12 neurites in the absence of exogenous NGF. This activity does not appear to be due to NGF.
我们通过将雪旺细胞与经神经生长因子（NGF）预处理致敏的对NGF有反应的PC12嗜铬细胞瘤细胞共培养，研究了小鼠和大鼠神经节雪旺细胞作为神经突生长促进因子可能来源的情况。当提供适当的神经突促进因子（如NGF）时，经NGF致敏的PC12细胞能够进行神经突再生。在没有外源性NGF的情况下，当将致敏的PC12细胞与雪旺细胞共培养时，直接接触雪旺细胞的PC12细胞会变大变平，在一天内呈现出神经元样形态。当与雪旺细胞建立接触时，PC12细胞在共培养的第一天就开始再生神经突，并且在整个实验过程（7周）中一直保持。大多数与雪旺细胞在相同的胶原包被培养皿中培养但未直接接触的PC12细胞未能再生神经突。相反，它们开始增殖，形成细胞簇。与雪旺细胞接触的PC12细胞的神经突再生不受抗NGF抗体的阻断。这些结果表明，在雪旺细胞表面附近存在一种神经突促进活性，其能够在没有外源性NGF的情况下引发PC12神经突的再生和长期维持。这种活性似乎不是由NGF引起的。
