Figure 4.

Loss of VEGF- and PlGF-dependent macrophage migration in flt-1^TK−/− homozygous mice. (A) Reverse transcription–PCR used for the detection of flt-1 mRNA in mouse macrophages. Primers: #9F (exon 9 forward primer) and #11R (exon 11 reverse primer) for the extracellular domain (Top), #17F (exon 17 forward primer) and #18R (exon 18 reverse primer) for kinase domain (Middle), and mouse β actin primers (Bottom). (B) VEGF₁₆₅ or PlGF-2 at different concentrations, as well as Zymosan-activated serum (ZAS), were added to the lower chamber of the Boyden chamber apparatus. The results are mean percentages (±SD) of migrated cells in 10 high-power fields. For each experiment, 4–5 wild-type or flt-1^TK−/− homozygous mice were used, and each experiment was carried out in triplicate. The mean numbers of migrated macrophages without chemoattractant were shown as 100 and compared with those with chemoattractants. (The real mean numbers of migrated macrophages without chemoattractant were 120 in the wild-type and 112 in the flt-1^TK−/− homozygous mice.)