Laminar flow

Stem Cells and Regeneration of the Auditory Nerve

Overview

Research Group Leader

Dr Bryony Nayagam

Cochlear implants function by electrically stimulating auditory neurons in the absence of hair cells, to enable hearing in severe to profoundly deaf individuals. The efficacy of this device therefore depends on a critical number of surviving auditory neurons. Stem cell transplantation therapy is emerging as a potential strategy for auditory nerve rehabilitation, as differentiated stem cells may provide a source of replacement auditory neurons to the deaf cochlea. The successful engraftment of stem cells into the cochlea will require both the directed growth of new processes and the formation of functional connections with existing structures, and we are investigating these questions using both in vitro and in vivo experimental models. We are particularly interested in whether transplanted stem cells are capable of making functional connections in the brainstem, thereby improving hearing with a cochlear implant.

Research domains: Bioscience; Clinical Sciences & Health Practice; Neurosciences & Behavioural Sciences

Research Activity

This Research Group has no available student projects at the moment, but if you're interested in undertaking research with this group please contact the Research Group Leader.

To find other available student projects use the research finder via the following link.


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Current Research

  1. Current in vivo studies are directed towards the delivery of differentiated stem cells directly into the auditory nerve and combined electrical stimulation from a cochlear implant to test if exogenous neurons are capable of making functional connections in the deafened cochlear environment.
  2. Current in vitro projects are investigating whether these stem cell-derived neurons are electrically active and capable of forming synapses on hair cells in extended tissue culture.

Current Students

Tomoko Hyakumura, PhD candidate
“Peripheral and central innervation of human embryonic stem-cell derived neurons in vitro”

Niliksha Gunewardene, PhD candidate
“The potential of induced pluripotent stem cells to rehabilitate the deaf mammalian cochlea”

Patrick Atkinson, PhD candidate
“Gene therapy after hearing loss for long-term neural protection”

Current Staff

  • Dr Mirella Dottori, Research Fellow

Featured Grants

  • NHMRC Project Grant. Can stem cells make functional connections? 2012.
  • Garnett Passe & Rodney Williams Memorial Fund Project Grant. Restoring hearing in the deaf cochlea using stem cells and electrical stimulation, 2010.
  • Royal Victorian Eye & Ear Hospital Small Research Grant. Combined treatment for hearing loss using stem cells and electrical stimulation, 2011.
  • Royal Victorian Eye & Ear Hospital Small Research Grant. Differentiation of sensory neural progenitors using early postnatal cochlear explant cultures, 2009.

Featured Publications

  1. NAYAGAM, B. A., & MINTER, R. L. 2012. A comparison of treatments for directing the differentiation of stem cells toward a sensory neural fate. American Journal of Otolaryngology, 33, 37 - 46.
  2. NAYAGAM, B. A., MUNIAK, M. A., & RYUGO, D. K. 2011. The spiral ganglion: connecting the peripheral and central auditory nervous systems. Hearing Research, 278, 2 - 20.
  3. ADDAMS-WILLIAMS, J., MUNAWEERA, L., COLEMAN, B., SHEPHERD, R. K. & BACKHOUSE, S. 2011. Cochlear implant electrode insertion: in defence of cochleostomy and factors against the round window membrane approach. Cochlear Implants International. Aug:12 Suppl 2, S36 - 9.
  4. COLEMAN, B., RICKARD, N.A., DE SILVA, M. G., & SHEPHERD, R. K. 2009. A protocol for cryoembedding the adult guinea pig cochlea for fluorescence immunohistology. J Neurosci Meth, 176, 144 -51.
  5. BACKHOUSE, S., COLEMAN, B. & SHEPHERD, R. K. 2008. Surgical access to the mammalian cochlea for cell-based therapies. Experimental Neurology. 214, 193 - 200.

Collaborations

  • Eaton-Peabody Laboratory, Harvard University, USA
  • John Hopkins University, USA
  • Bionics Institute, Melbourne