FIG 4 .

Recombinant UL7 promotes HAEC tube formation. Increasing concentrations (50, 150, and 300 ng/ml) of pUL7Fc were directly added to serum-free basal media in the presence or absence of neutralizing antibodies against UL7 or the isotype control (iso ctl). Controls included HAEC stimulated with 300 ng/ml of Fc and 300 ng/ml of CEACAM1Fc. (A) Quantitative measures of angiogenesis consisted of the numbers of lumens and branch points. Three independent experiments were performed. Data are expressed as means ± SEM of the results of three independent biological replicates for each condition assayed in triplicate. Statistical significance is represented with three asterisks (***; P < 0.001) or with two asterisks (**; P < 0.01). (B) Representative examples of Fc, pUL7Fc, and pUL7Fc plus αUL7 (pUL7Fc+αUL7) are shown as a high-power image (magnification, ×20).