Effect of human germinal sheathed cells injected into the brain on neurological and motor function impairment in rats after traumatic brain injury

Yuhe HAN; Ranbo Lü; Wanhong ZHANG; Jianping ZHANG

ABSTRACT

BACKGROUND:

One of the main causes of the failure of central nerve regeneration is that the microenvironment (lack of nerve growth factor, inhibitory factor produced by excretion and formation of glial scar) in the injured central nerves is not favorable for the regeneration of axons. Therefore, it is important to improve the microenvironment of injured area for the regeneration of axons. Recently, olfactory ensheathing cells (OECs) have been attracting much attention as a key method to treat central nervous injury.

OBJECTIVE:

To investigate the effect of OECs on traumatic brain injury (TBI) in rats and whether they can reduce neurological impairment after TBI.

DESIGN:

A randomized controlled experimental trial based on experimental animals.

SETTING:

Department of neurosurgery in a hospital affiliated to a university.MATERIALS The experiment was conducted in the Central Laboratory of Department of Neurosurgery, Kaifeng Railway Hospital from April 2003 to August 2003. Altogether 100 healthy adult SD rats of either gender,weighting 250- 350 g, were randomly divided into four groups normal group, TBI group, normal saline group and OEC group with 25 rats in each. Each group was further divided into five subgroups with 5 rats in each.

INTERVENTIONS:

The models of TBI in rats were established, and OECs were transplanted into brain tissues immediately after injury. The scores of nerve injury were assessed in the rats at day 1, day 4, week 1, week 2 and week 4. The distribution of OECs in brain tissues was observed after the rats were sacrificed.MAIN OUTCOME

MEASURES:

Neurological function recovery of rats and distribution of OECs in brain tissues.

RESULTS:

At week 2 and week 4 after operation, neurological severity scores (NSS) in OEC group significantly differed from those of TBI group and normal saline group. HE staining or immunohistochemistry of GFAP and p75 revealed that OECs could survive in the transplanted site and migrate toward the surrounding tissues. The total number of p75 positive cells in five coronal tissue slices of 6 μm thick was added up at different intervals. The results showed that the number of OECs was decreased with the passing time.

CONCLUSION:

OECs can survive in the transplanted site and migrate to the surrounding tissues when they are transplanted into the iujured brain tissues immediately after TBI. Giving OECs can reduce neurological and motor dysfunction induced by TBI.