Objective:To observe the morphological features ofgreen fluorescent protein-olfactory ensheathing cells(GFP-OECs)cultured in vitro and transplanted into injured spinal cord of rats

and study the influence of pathological environment of spinal cord injury and GFP on their morphology. Methods:Outermost olfactory ensheathing cells were isolated from the olfactory bulbs of adult green fluorescent protein transgenic rats

OECs were cultured by enzyme digestion.The cells were observed and photographed regularly with light microscope

laser scanning confocal microscope and transmission electron microscope before transplantation in order to observe their morphological characteristics in vitro culture. When the cells were cultured in medium for 10 days

the cells were transplanted into contusion area of T 10 spinal cord in SD rat with microsurgical technique. The GFP-OECs in spinal cord injury were observed with light and electron microscopes after 7 and 15 days. Results:After primary cultured for 7 days

strong green fluorescence staining of GFP-OECs were observed

GFP-OECs appeared three typical morphology:dipolar

tripolar and oblate

but mainly dipolar.After primary cultured for 10 days

major cells were dipolar. After transplanted into injured spinal cord

the cells were dipolar

the nuclei were irregular

and there were rich rough endoplasmic reticulums

free ribosomes and mitochondrion in the cytoplasm. Conclusion:The morphology of OECs is not effected by GFP. There is no significant morphological difference of GFP-OECs before and after transplantation

the appearance of GFP-OECs do not change in injured spinal cord in its early stage.