Takayuki Nakagawa

Immune-mediated inner ear disorder has been well established as a clinical entity; however, the innate immune system of the inner ear is a poorly understood area of research with high clinical and immunological importance. Although the presence of resident tissue macrophages in the inner ear has been suggested, there has been some controversy. In this study, we analyzed the origin of cochlear resident macrophages and the contribution of hematopoietic bone marrow (BM) to the recruitment of macrop

These findings demonstrate that local IGF-1 application through the biodegradable hydrogel has the potential for protection of cochleae from noise trauma.

These findings indicate that PLGA nanoparticles can be an useful drug carrier to the cochlea via local application.

These findings indicate that biodegradable hydrogels can be used for drug delivery to the inner ear.

These findings indicate that local rhIGF-1 treatment via gelatin hydrogels is effective for treatment of NIHL.

Topical IGF1 application using gelatin hydrogels is well tolerated and may be efficacious for hearing recovery in patients with SSHL that is resistant to systemic glucocorticoids.

This study examined the potential of induced pluripotent stem (iPS) cells for use as a source of transplants for the restoration of auditory spiral ganglion neurons. We monitored neurite outgrowth from iPS cell-derived neural progenitors toward cochlear hair cells ex vivo, and followed their survival and fates after transplantation into mouse cochleae in vivo. Neurons derived from iPS cells projected neurites toward cochlear hair cells. The settlement of iPS cell-derived neurons was observed 1 w

UMIN Clinical Trials Registry Number UMIN000004366, October 30th, 2010.

This study aimed to evaluate the potential of embryonic stem cell-derived neural progenitors for use as transplants for the replacement of the auditory primary neurons, spiral ganglion neurons. Mouse embryonic stem cell-derived neural progenitors were implanted into the base of the cochlear modiolus of normal or deafened guinea pigs, which contains spiral ganglion neurons and cochlear nerve fibers. Histological analysis demonstrated the survival and neural differentiation of transplants in the c

The predictable fashion of induction of apoptosis in SG neurons over a well-defined time course in the model in the study will aid studies of the molecular mechanism of cell death and elucidation of a strategy for prevention of SG degeneration.

Lidocaine-loaded PLGA microparticles were shown to be capable of the sustained delivery of lidocaine into the cochlea, suggesting that they could be used for the attenuation of peripheral tinnitus.

SV atrophy appears to be the most prominent anatomic characteristic of aged human cochleae.