Differentiation of Human Mesenchymal Stem Cells to Otic Progenitor-like Cells

Abstract

Objectives:

Differentiate mesenchymal stem cells to otic progenitor-like cells.

Methods:

We isolated and cultured the stromal vascular fraction (SVF) of 3 samples of human adipose tissue. We differentiated human adipose stem cells (hASCs) to otic lineage, using a differentiation medium containing DMEM HG, F12, N2, B27 and different growth factors like FGF3, FGF10, EGF, and IGF-1. The differentiated cells were fixed and RNA extracted at day 10 and 38 to analyze the expression of otic progenitor, neuronal or inner ear hair cell markers.

Results:

After 10 days of differentiation we detected otic placode markers expression: Pax2 (90.9 ± 0.16%), Pax8 (44.2 ± 0.03%), and BMP7 (86.4 ± 0.24%). Brn3.c (24.2 ± 0.05%), MyoVIIa (10.8 ± 0.05%), and BIII tubulin (28.8 ± 0.37%) were also detected, consistent with the presence of progenitors of sensorineural and inner ear hair cells. At day 38, an increase of inner ear hair cell markers (33.2 ± 0.04% MyoVIIa, 33.9 ± 0.3% Brn3.c and 14.3% Math1), a decreased of otic progenitor markers (46.2% Pax2 and 15.9% Pax8) and absence of neural markers were seen. The same pattern was seen at mRNA level.

Conclusions:

Even though these results are preliminary and a protocol improvement is necessary, this work demonstrates the ability of hASCs to differentiate into otic lineage, opening a door to a future therapeutic option for sensorineural hearing loss.