Figure 5. Acidic culture conditions inhibit cell cycle progression in human NP-MSCs which can be reversed using ASICs inhibitors. Flow cytometric DNA content profiles comparing cultured NP-MSCs derived from Pfirrmann grade II (A) and IV (B) cases cultured under control or acidic pH conditions in combination with or without treatment using Amiloride, PcTx1, APETx2, respectively. G0/G1, S and G2/M cell cycle phases were estimated as % totals using the ModFit software. The samples in (A) were from case 6 and that in (B) from case 11.