Fig. 5.

Expression analysis of collagen genes using real-time polymerase chain reaction (PCR). RNA from uninjured untreated control disks and injured disks treated with neonatal human dermal fibroblasts (nHDFs) or saline was isolated for real-time PCR analysis. (A–C) At 2 and 8 weeks after treatment, expression levels of collagen types II, I, and III genes were analyzed. (D) The ratio of collagen II (Col II) to collagen I (Col I) gene expression was calculated and normalized to that of the saline treated disks. Error bars represent the standard error of the mean.