This MAb recognizes proteins of 19-22 kDa (reducing) and 38 kDa-44 kDa (non-reducing), identified as various isoforms of Vascular Endothelial Growth Factor or Vascular Permeability Factor (VEGF/VPF) . It is highly specific to VEGF, which is a homodimeric, disulfide-linked glycoprotein with a close homology to platelet-derived growth factor (PDGF) . There are multiple isoforms of VEGF containing 206-, 189-, 165-, and 121-amino acid residues. The smaller two isoforms, VEGF165 and VEGF121, are secreted proteins and act as diffusible agents, whereas the larger two remain cell associated. VEGF/VPF plays an important role in angiogenesis, which promotes tumor progression and metastasis. Primary antibodies are available purified, or with a selection of fluorescent CF® Dyes and other labels. CF® Dyes offer exceptional brightness and photostability. Note: Conjugates of blue fluorescent dyes like CF®405S and CF®405M are not recommended for detecting low abundance targets, because blue dyes have lower fluorescence and can give higher non-specific background than other dye colors.