Notch and patched pathway members are differentially expressed in hMAPCs and hAC133⁺ cells. Q-RT-PCR analysis of members of the patched pathway (Shh, patched-1, and patched-2) (A) and the Notch pathway (Notch-1, -2, -3, and -4 and ligands Dll-1, -3, -4, and Jagged-1 and -2) (B) known to be involved in AV specification. Note differences in expression (see “Results”) between hMAPCs compared with hAC133⁺ cells. The mRNA levels in all panels are expressed in percentage versus a positive control (total RNA) and were normalized by using GAPDH as housekeeping gene. The mean (± SEM) of 3 different experiments in triplicate is shown. *P < .05; **P < .01 versus hAC133⁺ cells.