Table 2.
Cell transplantation studies in the inner ear.
| Recipient species | Hearing status | Donor species & Cell type | Period of treatment |
Observations | Reference |
|---|---|---|---|---|---|
| Adult mouse | Deaf, 3 days (neomycin) | Mouse; fetal neural stem cells | 25 days | - grafted cells observed in perilymphatic and endolymphatic spaces of inner ear, in both cochleae and vestibules - cell survival after 25 days - cells expressed glial (GFAP)1 and neuronal (MAP2)1 markers |
(Tateya et al., 2003) |
| Newborn rat | No intervention | Rat; adult neural stem cells | 2 or 4 weeks | - cells localised to region of organ of Corti - cell survival for up to four weeks - differentiation into neurons, astrocytes and oligodendrocytes |
(Ito et al., 2001) |
| Adult rat | - Normal hearing - Deaf, 1 week (neomycin) |
Mouse; fetal dorsal root ganglia | 3, 6 or 10 weeks | - cells survived for up to 10 weeks - localised close to organ of Corti and SGNs |
(Hu et al., 2004) |
| Adult chinchilla | Deaf, 4 weeks (gentamycin/ethacrynic acid) | Chinchilla; bone marrow stromal cells | 3 weeks | - cell migration through all cochlear turns - cells in scala vestibuli, scala tympani, cochlear lateral wall and modiolus - cell survival after three weeks - expressed neuronal (neurofilament) or glial (GFAP) markers |
(Naito et al., 2004) |
| Adult mouse | No intervention | Mouse; embryonicneural stem cells | 28 days | - migration through all cochlear turns - most surviving cells in perilymphatic space - cell survival after four weeks - most cells expressed glial (GFAP) markers |
(Iguchi et al., 2003) |
| P21 rats | - Normal hearing - Acoustic overstimulation |
Rat; fetal otocyst cells | 1 month | - cell survival for one month - cells observed in lateral wall, modiolus, scala tympani, scala vestibuli |
(Kojima et al., 2004) |
| Adult mouse | Deaf, 1 day (neomycin) | Mouse; embryonic stem cells | 4 weeks | - cells found in vestibular and cochlear regions - most cells expressed markers for undifferentiated stem cells (SSEA3)1 and for neurons (βIII-tubulin; NCAM)1 |
(Sakamoto et al., 2004) |
| Embryonic chicken | No intervention | Mouse; embryonic stem cells | 48 hours | - cells identified in the otic vesicles, but not as part of the otic vesicle walls | (Sakamoto et al., 2004) |
| Guinea pig | - Normal hearing - Deaf, 7 days (neomycin) |
Guinea pig; fetal dorsal root ganglia | 21-22 days | - implant commonly attached close to spiral lamina and organ of Corti - some migration into the modiolus - animals receiving concurrent neurotrophic factor treatment showed increased survival |
(Olivius et al., 2003) |
| Guinea pig | - Normal hearing - Deaf |
Mouse; embryonic stem cells | 13 days | - good cell survival in scala tympani - labelling of neurofilament and nestin in some of the surviving cells |
(Altschuler et al., 2003) |
| Guinea pig | - Normal hearing - Deaf, 2 days (neomycin) |
Mouse; adult neural stem cells | 1-4 weeks | - cells located near Rosenthal's canal, organ of Corti and along peripheral processes; also seen in scala tympani and scala vestibuli - poor cell survival - cells expressed neuronal (βIII-tubulin) and glial (GFAP) markers |
(Hu et al., 2005) |
| Guinea pig | - Deaf , 2 or 4 weeks (kanamycin/frusemide) | Rat; sciatic nerve Schwann cells | 2 weeks | - cells located within scala tympani of basal turn - enhanced SGN survival |
(Andrew, 2003) |
| Guinea pig | - Deaf , 2 or 4 weeks (kanamycin/frusemide) | Mouse; embryonic stem cells | 1,2 or 4 weeks | - cell survival for up to four weeks - cells observed in all turns, in scala tympani and scala vestibuli - some neurofilament labelling |
(Coleman et al., 2005) |
1
GFAP = glial fibrillary acidic protein; MAP 2 = microtubule associated protein; SSEA3 = stage specific embryonic antigen-3; NCAM = neural cell adhesion molecule