Fig. 5.
The tilted peptides of SIV pg32 and the β-amyloid peptide inhibit angiogenesis. (A) poSIV and poBamyl inhibit ABAE cell proliferation. Proliferation was assessed by measuring [3H]thymidine uptake. Cells were treated with 1% FCS and 1 ng/ml basic FGF (bFGF) and increasing concentrations of fusion proteins (80, 160, or 320 nM poSIV or poBamyl, 640 nM MBP*) or with 10 nM 16K hPRL (16K PRL). The data are expressed as percentages of the incorporation measured with 1% FCS and 1 ng/ml bFGF alone. (A and B) Each bar represents a mean ± SD, n = 3. (B) The poSIV and poBamyl fusion proteins activate caspase-3 in BACE cells. BACE cells were treated for 18 h with the indicated protein (40, 80, or 160 nM poSIV or poBamyl). We used 10 nM 16K hPRL (16K PRL) as a positive control and 640 nM MBP* as a negative control. Each result is expressed as an enhancement factor [treated vs. untreated (Un) cells]. (C and D) poSIV and poBamyl inhibit capillary network organization in vitro. BACE cells were plated between two collagen gels and treated with the indicated protein for 16 h. Living cells were labeled with calcein-AM. (C) Photographs were taken under a fluorescence microscope. (D) Quantitative analysis of network structure performed by measuring tube lengths. Each bar represents a mean ± SD, n = 3. (E and F) poSIV and poBamyl inhibit capillary formation in vivo. (E) Representative examples of CAM are taken from a typical experiment. (F) Quantification was done by measuring the area devoid of capillaries in the region surrounding the disk. Values are means ± SD, n (poSIV) = 6, n (poBamyl) = 8, and n (MBP) = 7. ∗, P < 10−3 vs. MBP*; ∗∗, P < 10−2 vs. MBP*.