Effect of Nrp1 silencing on HS3ST3B-mediated protection against apoptosis. Parental (pEmpty) and HS3ST3B expressing (clones C and D) cells were transfected with siNrp1 or siCtrl and then cultured for 24 h in complete medium. After wash, cells were collected and cultured in medium containing 1% FCS in the absence (control) or presence of a mixture of anti-Fas antibody (100 ng/mL) and TNF-α (100 ng/mL) for 24 h. Thereafter, the number of viable cells was estimated by using MTS assay. Results are expressed as fold changes by comparison with the parental cells that have been transfected with siCtrl and cultured in the absence of pro-apoptotic stimulus. Data correspond to means ± S.D. from three independent experiments (*** p < 0.001, significantly different when compared with the parental cells; #
p < 0.05, ###
p < 0.001, significantly different when compared with the siCtrl-treated cells; n.s., not significant).