Scanning Electron Microscopic Examination of the Extracellular Matrix in the Decellularized Mouse and Human Cochlea
- 428 Downloads
Decellularized tissues have been used to investigate the extracellular matrix (ECM) in a number of different tissues and species. Santi and Johnson JARO 14:3-15 (2013) first described the decellularized inner ear in the mouse, rat, and human using scanning thin-sheet laser imaging microscopy (sTSLIM). The purpose of the present investigation is to examine decellularized cochleas in the mouse and human at higher resolution using scanning electron microscopy (SEM). Fresh cochleas were harvested and decellularized using detergent extraction methods. Following decellularization, the ECM of the bone, basilar membrane, spiral limbus, and ligament remained, and all of the cells were removed from the cochlea. A number of similarities and differences in the ECM of the mouse and human were observed. A novel, spirally directed structure was present on the basilar membrane and is located at the border between Hensen and Boettcher cells. These septa-like structures formed a single row in the mouse and multiple rows in the human. The basal lamina of the stria vascularis capillaries was present and appeared thicker in the human compared with the mouse. In the mouse, numerous openings beneath the spiral prominence that previously housed the root processes of the external sulcus cells were observed but in the human there was only a single row of openings. These and other anatomical differences in the ECM between the mouse and human may reflect functional differences and/or be due to aging; however, decellularized cochleas provide a new way to examine the cochlear ECM and reveal new observations.
Keywordscochlea SEM decellularized mouse human
The authors would like to thank Meredith Adams, M.D., for perfusing one of the human cochleas with SDS. Funding was provided to PAS by the NIDCD (RO1DC007588, U24DC011968), the Capita Foundation, and the Lions Hearing Foundation. The authors would like to thank Gail Celio at the University Imaging Centers for excellent assistance with SEM. Additional funding was supported by research of the European Community Research, Human stem cell applications for the treatment of hearing loss. Grant agreement no. 603029. Project acronym: OTOSTEM (HRA).
- Iurato S (1967) Submicroscopic structure of the inner ear. Pergamon Press, LondonGoogle Scholar
- Kleppel MM, Kashtan C, Santi PA, Wieslander J, Michael AF (1989b) Distribution of familial nephritis antigen in normal tissue and renal basement membranes of patients with homozygous and heterozygous Alport familial nephritis. Relationship of familial nephritis and Goodpasture antigens to novel collagen chains and type IV collagen. Lab Invest 61:278–289PubMedGoogle Scholar
- Lim DJ (1969) Three dimensional observation of the inner ear with the scanning electron microscope. Acta Otolaryng Suppl 255Google Scholar
- Liu W, Atturo F, Aldaya R, Santi P, Cureoglu S, Obwegeser S, Glueckert R, Pfaller K, Schrott-Fischer A, Rask-Andersen H (2015) Macromolecular organization and fine structure of the human basilar membrane—RELEVANCE for cochlear implantation. Cell Tissue Res 360:245–262CrossRefPubMedPubMedCentralGoogle Scholar
- Santi PA (1988) Cochlear microanatomy and ultrastructure. In: Physiology of the Ear, Eds., AF Jahn and FR Santos-Sacchi. Raven, New York, pp 173–199Google Scholar