Figure 7.

Profiles of temporal gene expression determined by semi-quantitative and real-time RT-PCR in MSC pellet cultures genetically modified with BMP-2 and BMP-4. Genes analyzed include collagen type (COL) II, aggrecan core protein (AGC), cartilage oligomeric matrix protein (COMP), fibromodulin (FMD), SRY (sex determining region Y) - box9 (SOX9), COL I, COL X, osteopontin (OP), indian hedgehog (IHH), runt-related transcription factor 2 (RUNX2) and alkaline phosphatase (ALP). Primer sequences and product sizes are listed in Table 1, with elongation factor 1α (EF1α) serving as housekeeping gene and internal control. For each marrow preparation/patient, treatment group and time point indicated RNA was extracted from 10 aggregates, and four patients were analyzed depending on group and time point. For the semi-quantitative RT-PCR analyses (upper panels), values are mean +/- SD raw data of optical band intensities of RT-PCR products between groups and time points (one band per patient), which were normalized using the EF1α reaction products. Values of the real-time RT-PCR analyses (lower panels) represent mean expression ratios +/- SD normalized to the expression levels of the housekeeping gene EF1α and relative to values from undifferentiated monolayer MSCs. Asterisks indicate values that are statistically different (P < 0.05) from marker gene vector-transduced control cultures or between samples. BMP = bone morphogenetic protein; MSC = mesenchymal stem cell; SD = standard deviation.