Migration of olfactory ensheathing cells and their effects on neurological function recovery in rats with cerebral infarction

Zhihua YANG; Wenli SHENG; Minjian WANG

ABSTRACT

BACKGROUND:

Olfactory ensheathing cell (OEC) transplantation can promote the recovery of neurological function in rats with cerebral infarction, while the migratory pattern of transplanted OECs and the relationship between OECs migrated to various encephalic regions and plasticity upregulation and recovery of neurological function of the encephalic region are still unknown.

OBJECTIVE:

To observe the migratory pattern and therapeutic value of OEC transplantation in rats with cortical cerebral infarction.DESIGN, TIME AND

SETTING:

Randomized, controlled, cell transplantation observation experiment was conducted between June 2002 and January 2004 at the Laboratory of Department of Neurology, the First Affiliated Hospital of Sun Yet-San University and Animal Experimental Center of SUN YET-SEN University, Guangzhou, Guangdong Province, China.MATERIALS Sprague-Dowley rats, 2.5-month-old, were used for olfactory ensheathing cell culture. 150 Sprague-Dowley rats,60-90 days, were used to replicate stroke-prone reuovascular hypertensive rat model using two-kidney two-clip method.

METHODS:

We purified OECs with differential time adherent method and labeled OECs with Hoechst 33342 before transplantation. Seventy stroke-prone renovascular hypertensive rats were used to prepare middle cerebral artery occlusion model.model rats were randomly allocated to 3 groups to receive OEC transplantation peri-mfarct cortex transplantation group,contralateral cortex transplantation group and bilateral transplantation group.MAIN OUTCOME

MEASURES:

The recovery of motor and sensory function was observed at 2 weeks and 6 weeks after transplantation with behavior and sensory function examination; the survival and distribution conditions of transplanted ceils were observed under the fluorescence microscope.

RESULTS:

The recovery condition of motor and sensory function of rats in bilateral transplantation group was obviously better than that of rats in peri-infarct cortex transplantation group and contralateral cortex transplantation group (P ＜ 0.01), nerve fiber number and positive signal value of growth associated protein-43 in the marginal zone of cerebral infarction were also more than that in peri-infarct cortex transplantation group and contralateral cortex transplantation group. Transplanted cells in peri-infarct cortex transplantation group migrated to infarct and contralateral cortex along corpus callosum, transplanted cells in contralateral cortex transplantation group migrated to midline and infarct cortex along corpus callosum, transplanted ceils in bilateral transplantation group migrated along corpus callosum and could be seen in bilateral cortices while more in infarct cortex.

CONCLUSION:

Transplanted OECs can survive for a long time period, and these cells not only confine to injection point but also can migrate to infarct and contralateral cortex along corpus caliosum to promote the recovery of neurological function of rats with cerebral infarction, the effect is more significant in bilateral transplantation.