FIGURE 2.

NEU1 catalytic activity required for inhibition of tube formation. A, HPMECs were infected with increasing MOIs of Ad-NEU1-G68V, an Ad encoding for a catalytically dead NEU1 mutant, and lysed, and the lysates were processed for NEU1 immunoblotting. To control for protein loading and transfer, the blots were stripped and reprobed for β-tubulin. IB, immunoblot; IB*, immunoblot after stripping. Molecular mass in kDa is indicated on left. The blot is representative of two independent experiments. B, HPMECs and HPMECs infected with Ad-GFP (MOI = 100), Ad-NEU1 (MOI = 100), or Ad-NEU1-G68V (MOI = 50, 100, and 200), at 1.5 × 10⁴ ECs/well, were incubated for 6 h on Matrigel, at which time they were photographed, and branches of capillary-like tubes were counted. Each bar represents mean ± S.E. (error bars) branches/HPF. The MOI and n for each condition are indicated below each bar. *, significantly decreased compared with the simultaneous Ad-GFP-infected control at p < 0.05.