Effect of epidermal growth factor and basic fibroblast growth factor on neural stem cells isolated from subventricular zone of human embryonic brain

Xiaojuan YIN; Zhichun FENG

ABSTRACT

BACKGROUND:

Pleiotropia and indeterminateness of the differentiation of neural stem cells (NSCs) cause great difficulties for clinical application.Therefore,it is the key to solving the problem to investigate the proliferation and differentiation condition of NSCs.

OBJECTIVE:

To observe the effects of epidermal growth factor(EGF)and basic fibroblast growth factor (bFGF) on the proliferation and differentiation of neural stem cells of human embryonic brain.

DESIGN:

A randomised and controlled experiment taking cultured human embryonic stem cells as subjects.

SETTING:

Department of Pediatrics of Zhujiang Hospital, the First Military Medical University of Chinese PLA.MATERIALSThis experiment was conducted at the Central Laboratory of the Department of Pediatrics of Chinese PLA from January to May 2004.Two 16-week embryos from induced labor by water bags voluntarily were chosen at random from the Department of Obstetrics in a tertiary hospital in Guangzhou(Informed consent was obtained from the parents of the fetuses).Then,cells in the subventricular zone were cultured in serum-free medium and serum medium, respectively.

METHODS:

Primary cells of subventricular zone of human embryonic brain were cultured with serum-free nedium containing EGF,bFGF and EGF + bFGF.The concentration of two growth factors was both 20 μg/L;experiment of differentiation was performed on the cell neurospheres cultured from the primary generation with serum culture medium;differentia tive cells were detected with immonohistochemical technique.MAIN OUTCOME

MEASURES:

The number of neurospheres and the change of neurons and gliocytes from neurospheres in each group.

RESULTS:

① There was no significant difference in the number of primary neurospheres between bFGF group and EGF+bFGF group [(150.3±14.9) /well vs (173.6±26.4)/we11, P ＞ 0.05] , but the number in the two groups was both more than that in EGF group [(99.5±14.9)/we11, P ＜ 0.01].② The neurons differentiated from neurospheres in bFGF group and EGF+bFGF group outnumbered those in EGF group, but gliocytes in EGF group outnumbered those in EGF + bFGF group.

CONCLUSION:

① bFGF can promote the proliferation of neural stem cells of subventricular zone of human embryonic brain,and the formed neurospheres can differentiate more neurons.② Combination of EGF and bFGF is not superior to single bFGF in effect,suggesting that there is no synergistic effect.