mostly to induce skeletal muscle differentiation is sufficient to deplet serum, thus you could use DMEM-F12+1% Horse Serum (you can increase HS up to 5%) when cells are 100% confluent. Otherwise some protocols use dexametason and/or insulin or even MyoD-ER transfection inducible by Tamoxifen exposure.
The differentiation medium you can use is DMEM/Ham’s F-12 + 2% donor horse serum (DHS) + 1% L-Glutamine + 1% P/S + 0.4 μg/ml dexamethasone + 1 ng/ml bFGF
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