title: Protein-engineered hydrogel encapsulation for 3-D culture of murine cochlea.
abstract: OBJECTIVE
  Elastin-like protein (ELP) hydrogel helps maintain the three-dimensional (3-D) cochlear structure in culture.
  
  
  BACKGROUND
  Whole-organ culture of the cochlea is a useful model system facilitating manipulation and analysis of live sensory cells and surrounding nonsensory cells. The precisely organized 3-D cochlear structure demands a culture method that preserves this delicate architecture; however, current methods have not been optimized to serve such a purpose.
  
  
  METHODS
  A protein-engineered ELP hydrogel was used to encapsulate organ of Corti isolated from neonatal mice. Cultured cochleae were immunostained for markers of hair cells and supporting cells. Organ of Corti hair cell and supporting cell density and organ dimensions were compared between the ELP and nonencapsulated systems. These culture systems were then compared with noncultured cochlea.
  
  
  RESULTS
  After 3 days in vitro, vital dye uptake and immunostaining for sensory and nonsensory cells show that encapsulated cochlea contain viable cells with an organized architecture. In comparison with nonencapsulated cultured cochlea, ELP-encapsulated cochleae exhibit higher densities of hair cells and supporting cells and taller and narrower organ of Corti dimensions that more closely resemble those of noncultured cochleae. However, we found compromised cell viability when the culture period extended beyond 3 days.
  
  
  CONCLUSIONS
  We conclude that the ELP hydrogel can help preserve the 3-D architecture of neonatal cochlea in short-term culture, which may be applicable to in vitro study of the physiology and pathophysiology of the inner ear.
authors.affiliation: *Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine; and †Departments of Bioengineering, and ‡Materials Science and Engineering, Stanford University School of Engineering, Stanford, California, U.S.A.
authors.forename: David T
authors.initials: DT
authors.lastname: Chang
authors.forename: Renjie
authors.initials: R
authors.lastname: Chai
authors.forename: Rebecca
authors.initials: R
authors.lastname: DiMarco
authors.forename: Sarah C
authors.initials: SC
authors.lastname: Heilshorn
authors.forename: Alan G
authors.initials: AG
authors.lastname: Cheng
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000502:physiology*; D003051:Cochlea / Q000378:metabolism*; D006198:Hair Cells, Auditory / Q000166:cytology* / Q000378:metabolism; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D051379:Mice; D009924:Organ Culture Techniques / Q000379:methods*
chemical_list: D020136:Hydrogel, Polyethylene Glycol Dimethacrylate
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