Objective: Previous reports showed that mouse embryonic fibroblasts (MEFs) could support pluripotent stem cell selfrenewaland maintain their pluripotency. The goal of this study was to reveal whether the decellularized extracellularmatrix 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 identificationof inner ear-derived cells was conducted by using reverse transcription-polymerase chain reaction (RT-PCR). Cellcounting kit-8 (CCK-8) was used to evaluate the proliferation capability of inner ear-derived cells cultured on the MEFECMand tissue culture plate (TCP).Results: The MEF-ECM was clearly observed after decellularization via SEM, and the immunofluorescence stainingresults revealed that MEF-ECM was composed of three proteins, including collagen I, fibronectin and laminin. Mostimportantly, the results of CCK-8 showed that compared with TCP, MEF-ECM could effectively facilitate the proliferationof inner ear-derived cells.Conclusion: The discovery of the potential of MEF-ECM in promoting inner ear-derived cell proliferation indicatesthat the decellularized matrix microenvironment may play a vital role in keeping proliferation ability of these cells. Ourfindings indicate that the use of MEF-ECM may serve as a novel approach for expanding inner ear-derived cells andpotentially facilitating the clinical application of inner ear-derived cells for hearing loss in the future
