Modified paraffin-embedding method for the human cochlea that reveals a fine morphology and excellent immunostaining results

Abstract

Conclusion: A modified paraffin-embedding method could be applied to histopathological and immunohistochemical studies of the human cochlea. The complementary use of molecular and immunohistochemical techniques by means of this method is thus considered to be a valuable tool for the future study of the human inner ear. Objective: To propose a new paraffin-embedding method for the morphological and immunohistochemical study of the human cochlea. Methods: Five human temporal bones were harvested at autopsy. The temporal bone specimens were fixed in 20% buffered formalin, decalcified with EDTA, cropped to a cube of approximately 15 mm, embedded in paraffin, and then cut into 6 μm thick sections. The sections were stained with hematoxylin and eosin, and immunostained with anti-prestin and anti-neurofilament antibodies. Results: Although paraffin-embedded sections cannot show the excellent morphology of the delicate membranous labyrinth obtained with celloidin, this technique successfully preserved the morphology of the cochlea, especially the organ of Corti, thereby enabling us to obtain excellent immunostaining results.

Keywords::

• Human temporal bone
• cochlea

Acknowledgments

This study was supported by Grants-in-Aid for Scientific Research (nos 18791193 and 19791250) from the Ministry of Education, Culture, Sports, Science and Technology, Japan. The authors wish to thank Dr Wada, Tohoku University, Sendai; Ms Kubo, Tokyo Metropolitan Institute of Gerontology, Tokyo; and Dr Kubo, National Institute of Physiological Science, Okazaki, for much advice about immunostaining. We also thank Mr Goto, Mr Mukaiyama, Ms Hasegawa, and all other technicians in the Departments of Pathology of Tokyo Metropolitan Geriatric Hospital for their excellent pathological work. We also express our sincere gratitude to the deceased whose temporal bones contributed to this study.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.