EphrinB2 silencing in HUVEC and MSC reduces cord formation. Reduction of EphrinB2 mRNA levels in HUVEC and MSC by silencing with siRNA or shRNA measured by real-time RT-PCR. The results reflect the means (± SD) of 3 independent experiments (A). Representative images from Matrigel-supported cultures of control and EphrinB2-silenced (siRNA) HUVEC (B), control and EphrinB2-silenced MSC (siRNA) (C), cocultures of HUVEC and MSC (both silenced: HUVEC by siRNA, MSC by GFP-shRNA) (D), and cocultures of HUVEC and MSC in which HUVEC or MSC was silenced (E). Network formation in Matrigel-supported cocultures of HUVEC (control or siRNA) and MSC (control or shRNA) was measured as the mean number of angles (± SD) generated by intersecting cords from 3 separate experiments; ** P < .01 (F).