摘要BACKGROUND: Studies have demonstrated that olfactory mucosa can promote the regeneration and formation of axonal medullary sheath of injured neurons. To date, olfactory ensheathing cells (OECs) utilized in basic and clinical research arise primarily from the olfactory bulb mucosa. However, little is known regarding culture, purification, and biological properties of OECs.OBJECTIVE: To isolate and culture OECs utilized modified, differential attachment in combination with neurotrophic factor 3 (NT3) and low concentration serum to explore an optimal in vitro culture method for OECs.DESIGN, TIME AND SETFING: Single-sample observation was performed at the Medical Experimental Center of Stomatology College, Xi'an Jiaotong University between March 2006 and December 2007.MATERIALS: Twelve samples from aborted embryos, 4-6 months, were used to isolate OECs;rabbit-anti-human p75NIR and glial fibrillary acidic protein (GFAP) antibody were provided by Sigma, USA. METHODS: The differential time was six hours. This was repeated twice, based on Nash's differential attachment. Attached OECs were cultured in DMEM-F12 culture medium containing 10% fetal bovine serum (FBS) or 2.5% FBS and NT3.MAIN OUTCOME MEASURES: OEC morphology was observed, and p75NTR and GFAP immunocytochcmistry was used for identification and purity detection. RESULTS: Some cells attached after three days in culture. Several cells possessed short neurites with good refractivity. Some shuttle-shaped fibroblasts could be seen. On day six, more cells attached, exhibiting a three-dimensional appearance. Many cells appeared dipolar or tripolar, with slender neurites, and fibroblasts were clustered. On day nine, the number of dipolar or tripolar cell bodies with slender neurites was increased,and fibroblasts were clustered. On day 15, fibroblasts occupied the majority of the bottom of the culture bottle, with several OECs surviving at the upper layer. OECs were positive for P75NTR and GFAP expression,as identified by an immunocytologically stained brown cell body and neurites. However, fibroblasts were P75NTR and GFAP-negative. On day 9, OEC purity reached 81%, and the number of proliferating fibroblasts significantly increased. By the end of day 12, OEC purity was reduced to 56%.CONCLUSION: Modified differential attachment, in combination with low concentration serum and NT3,removes fibroblasts and reduces OEC loss. This is an appropriate method for the isolation and culture of human fetal ol factory mucosa-derived OECs.