Chemicals and reagents
Foetal bovine serum (FBS, No. 10099141), trypsin (No. 27250018), Dulbecco’s modified Eagle’s medium (DMEM, No. THP5218), L-Glutamine (No. 1816801), B-27 (No. 2004470), Neurobasal-A Medium (No. 1995169), and Roswell Park Memorial Institute 1640 (GI 1640) medium (No. 8119040) were purchased from Gibco Invitrogen Corporation (Carlsbad, CA, USA). Collagenase I (No. C0130-1G) and collagen (type I solution from rat tail, No. A10483-01) were obtained from Sigma-Aldrich (St. Louis, MO, USA). L-THP and OXA (No. D109812) were purchased from Aladdin Reagent Co., Ltd. (Shanghai, China).