title: Establishment of a long-term spiral ganglion neuron culture with reduced glial cell number: Effects of AraC on cell composition and neurons.
abstract: Sensorineural deafness is mainly caused by damage to hair cells and degeneration of the spiral ganglion neurons (SGN). Cochlear implants can functionally replace lost hair cells and stimulate the SGN electrically. The benefit from cochlear implantation depends on the number and excitability of these neurons. To identify potential therapies for SGN protection, in vitro tests are carried out on spiral ganglion cells (SGC).
  
  
  
  A glial cell-reduced and neuron-enhanced culture of neonatal rat SGC under mitotic inhibition (cytarabine (AraC)) for up to seven days is presented. Serum containing and neurotrophin-enriched cultures with and without AraC-addition were analyzed after 4 and 7 days.
  
  
  
  The total number of cells was significantly reduced, while the proportion of neurons was greatly increased by AraC-treatment. Cell type-specific labeling demonstrated that nearly all fibroblasts and most of the glial cells were removed. Neither the neuronal survival, nor the neurite outgrowth or soma diameter were negatively affected. Additionally neurites remain partly free of surrounding non-neuronal cells.
  
  
  
  Recent culture conditions allow only for short-term cultivation of neonatal SGC and lack information on the influence of non-neuronal cells on SGN and of direct contact of neurites with test-materials.
  
  
  
  AraC-addition reduces the number of non-neuronal cells and increases the ratio of SGN in culture, without negative impact on neuronal viability. This treatment allows longer-term cultivation of SGC and provides deeper insight into SGN-glial cell interaction and the attachment of neurites on test-material surfaces.
authors.affiliation: Department of Otolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany; Department of Zoology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany. Electronic address: schwieger.jana@mh-hannover.de.
authors.forename: Jana
authors.initials: J
authors.lastname: Schwieger
authors.affiliation: Department of Zoology, University of Veterinary Medicine Hannover, Bünteweg 17, 30559 Hannover, Germany. Electronic address: Kalle.Esser@tiho-hannover.de.
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Esser
authors.affiliation: Department of Otolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany; Cluster of Excellence Hearing4all, Germany. Electronic address: lenarz.thomas@mh-hannover.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Lenarz
authors.affiliation: Department of Otolaryngology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany; Institute of Audioneurotechnology, Hannover Medical School, Stadtfelddamm 34, 30625 Hannover, Germany; Cluster of Excellence Hearing4all, Germany. Electronic address: scheper.verena@mh-hannover.de.
authors.forename: Verena
authors.initials: V
authors.lastname: Scheper
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002452:Cell Count; D018929:Cell Culture Techniques; D048429:Cell Size / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003561:Cytarabine / Q000494:pharmacology; D005260:Female; D007150:Immunohistochemistry; D008297:Male; D050258:Mitosis Modulators / Q000494:pharmacology; D009457:Neuroglia / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D000071446:Neuronal Outgrowth / Q000187:drug effects; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D017207:Rats, Sprague-Dawley; D013136:Spiral Ganglion / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D013997:Time Factors
chemical_list: D050258:Mitosis Modulators; D003561:Cytarabine
keywords: AraC; Glial cells; Mitotic inhibition; Non-neuronal cells; Purification; Spiral ganglion neurons