Mouse Embryonic Fibroblasts-Derived Extracellular Matrix Facilitates Expansion of Inner Ear-Derived Cells.

Objective: Previous reports showed that mouse embryonic fibroblasts (MEFs) could support pluripotent stem cell selfrenewal and maintain their pluripotency. The goal of this study was to reveal whether the decellularized extracellular matrix derived from MEFs (MEF-ECM) is beneficial to promote the proliferation of inner ear-derived cells.

Materials and methods: In this experimental study, we prepared a cell-free MEF-ECM through decellularization. Scanning electron microscope (SEM) and immunofluorescent staining were conducted for phenotype characterization. Organs of Corti were dissected from postnatal day 2 and the inner ear-derived cells were obtained. The identification of inner ear-derived cells was conducted by using reverse transcription-polymerase chain reaction (RT-PCR). Cell counting kit-8 (CCK-8) was used to evaluate the proliferation capability of inner ear-derived cells cultured on the MEFECM and tissue culture plate (TCP).

Results: The MEF-ECM was clearly observed after decellularization via SEM, and the immunofluorescence staining results revealed that MEF-ECM was composed of three proteins, including collagen I, fibronectin and laminin. Most importantly, the results of CCK-8 showed that compared with TCP, MEF-ECM could effectively facilitate the proliferation of inner ear-derived cells.

Conclusion: The discovery of the potential of MEF-ECM in promoting inner ear-derived cell proliferation indicates that the decellularized matrix microenvironment may play a vital role in keeping proliferation ability of these cells. Our findings indicate that the use of MEF-ECM may serve as a novel approach for expanding inner ear-derived cells and potentially facilitating the clinical application of inner ear-derived cells for hearing loss in the future.