Effect of thalidomide on proliferation of ECs and capillarogenesis assay. (A) Effect of thalidomide on the proliferation of ECs from 18 patients. Cells (2 × 103) were incubated on days 0, 2, 4, and 6 in the complete medium (positive control), the starvation (FCS-free) medium (negative control), and in the positive control medium containing each thalidomide dose. Cells were counted on day 8. Significance determined by Wilcoxon rank test. Data shown are mean ± one SD. (B) Capillarogenesis assay on matrigel of one patient's ECs. Cells (2 × 105) were plated on matrigel and grown for 8 hours in the complete medium alone (i) or containing 10 μM thalidomide (ii). The medium gave cells arranged in branching, reciprocally anastomosing tubes forming a closely knit capillary-like plexus. The culture has area percentage of 26.2, length of 6814, branching of 41, and mesh of 35. Disaggregation of the plexus paralleled the exposure to thalidomide: area percentage of 15.5, length of 3250, branching of 25, and mesh of 8. Bar = 70 μm.
