FIG. 3.

Fisp12 protects HMVECs from apoptosis. HMVECs were starved for 24 h prior to the addition to slides coated with 10 μg of laminin (Collaborative biosciences) per ml overnight at 4°C. Cells were then incubated in EBM for 20 h with or without the addition of Fisp12 protein, and apoptosis was monitored by using the TUNEL assay; the number of apoptotic cells was then counted. (A) Dose dependence of Fisp12-promoted cell survival. Values for HMVECs incubated in the absence of Fisp12 (control) or in the presence of indicated concentrations of Fisp12 are shown. Where indicated, Fisp12 was preincubated with anti-Fisp12 antibody prior to addition to the medium. Complete medium was added as a positive control. The percentages of apoptotic cells ± the SD from at least 500 cells counted are shown, and each experiment was done in triplicate. (B) Cell proliferation assay. HMVECs treated as described in panel A were labeled with BrdUrd for 24 h, and the percentages of cells incorporating label in the absence or presence of Fisp12 are shown. (C and D) Photomicrographs of HMVECs incubated in the absence or presence of 5 μg of Fisp12 per ml, respectively.