Abstract
In cultivating human neuroblastoma cells maximum number of neurites per cell and length of the neurite were estimated as 5.5 and 2.2 (nm), respectively It was found that there was correlation between growth and differentiation of nerve cells. Maximum specific BDNF production rate was also calculated as 2.5$\times $10$^{-5}$(ng/cell/day) at 7$\times $ 10$^{5}$ (viable cells/ml) of maximum cell density, corresponding to 100 (ng/mL) of BDNF. The secretion of BDNF was occurred most in the later peroids of the cultivation, yielding 75 (ng/mL) of BDNF. The production of rate of BDNF was elongated in adding 1 ($\mu $g/mL) of BDNF as well as 40% increase of the length of the BDNF. It proves that BDNF can be used as one of biopharmaceuticals to treat age-related diseases such as Alzheimer's disease and Prakinson's disease. It can also provide the information of scaling-up mammalian cell cuture system to economically produce BDNF.