title: Survival-enhancing of spiral ganglion cells under influence of olfactory ensheathing cells by direct cellular contact.
abstract: The efficacy of cochlear implantation is primarily associated with the quantity and health of the remaining spiral ganglion cells (SGCs). Olfactory ensheathing cells (OECs) are capable of expressing a variety of growth factors and adhesion molecules, playing an important role in enhancing cellular survival. To investigate the effect of OECs on the survival of SGCs, co-cultures of OECs and SGCs were developed in this study. In addition, OECs conditioned medium (OEC-CM) was employed to culture SGCs in contrast with the co-cultures. OECs were identified immunocytochemically by low-affinity nerve growth factor receptor p75 (P75NTR) and glial fibrillary acidic protein (GFAP), while SGCs were stained with neuron-specific markerbetaIII-tubulin. SGCs survival was assessed in different conditions. To explore the underlying mechanism, growth factors, adhesion molecules and their receptors were investigate using RT-PCR. Our results indicate that the co-cultures of OECs and SGCs can be successfully established and that both OECs and OEC-CM promote SGCs survival in vitro. SGCs survival was most enhanced when co-cultured with OECs. Both Olfactory bulb (OB) and OECs were proved to express BMP-4 and NCAM while BMPR-1A and a7 integrin were also detected in cochlea and SGCs. In conclusion, our results suggest that enhancement in co-cultures is in part due to direct cellular contact. Transplantation of OECs may be a cell-based therapy for the application of neurotrophic factors to the inner ear.
authors.affiliation: Department of Otolaryngology, Eye Ear Nose and Throat Hospital, Shanghai Medical College of Fudan University, 83 Fen Yang Road, Shanghai 200031, PR China.
authors.forename: Quan
authors.initials: Q
authors.lastname: Liu
authors.forename: Jing
authors.initials: J
authors.lastname: Ye
authors.forename: Hongmeng
authors.initials: H
authors.lastname: Yu
authors.forename: Huawei
authors.initials: H
authors.lastname: Li
authors.forename: Chunfu
authors.initials: C
authors.lastname: Dai
authors.forename: Yurong
authors.initials: Y
authors.lastname: Gu
authors.forename: Yaying
authors.initials: Y
authors.lastname: Zhu
authors.forename: Zhicun
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002450:Cell Communication; D002470:Cell Survival; D002478:Cells, Cultured; D018920:Coculture Techniques; D009186:Myelin Sheath / Q000502:physiology*; D009830:Olfactory Bulb / Q000166:cytology*; D009832:Olfactory Nerve / Q000166:cytology; D051381:Rats; D013136:Spiral Ganglion / Q000166:cytology*