Immunoblotting of VEGF in human neutrophils' subcellular compartments. Specific and azurophilic granules membranes were prepared on Percoll gradients. The cavitate was recovered after neutrogen cavitation. Western blots were probed with a polyclonal anti-VEGF antibody. Human recombinant VEGF (R&D Systems) was loaded and blotted in parallel. The molecular masses of protein standards are indicated in kilodaltons.