Figure 6. Differential expressions of marker genes in vascular wall-derived MPSCs versus SMC.

(A) QRT-PCR analyses show that genes specific for SMC such as alpha smooth muscle actin (αSMA, ACTA2), TAGLN1 (transgelin), THSP1 (Thrombospondin 1), MYOC (myocardin) and HPLN1 hyaluronan and proteoglycan link protein 1 are expressed significantly higher in hAoSMC (human aortic smooth muscle cells) in comparison to MSCs while PDGFRα (platelet-derived growth factor α) and NG2 are expressed stronger in vascular wall-derived MPSCs (A–B). Stimulation of VW-MPSCs with VEGF165, PDGF-BB, FGF2 (10 ng/ml), TGFβ1 (5 ng/ml) alone or in indicated combinations for 14 days shows an up-regulation of SMC markers TAGLN and THSP1 as compared to VW-MPSCs cultured in normal growth media (NGM) (C). Resulting expression levels were normalized by division through the mean expression value of the reference gene (β-actin). Data are presented as mean ± SD from four independent experiments measured at least two times each. *, p<0.05; **, p≤0.005. The stimulation of VW-MPSCs by TGFß1 alone or in combination VEGF and PDGF also increases the protein level of SMC markers αSMA and TAGLN as shown by immunoblotting (D). Total cell lysates were generated by scraping cells in ice-cold RIPA buffer. Equal protein amounts were subjected for SDS-PAGE. TAGLN was detected by Western blot using chemiluminescence. β-actin was included as a loading control. Data representative for at least 3 independent experiments with similar results are shown.