Figure 2. Stability of extracellular PGRN in neuronal culture media.
35 nM of recombinant PGRN (see Methods) was added to neuronal cultures for various time periods as indicated. Elastase (0.3 U/ml) or mixture of elastase with protease inhibitor cocktail was added together with PGRN at the same time. Protease inhibitors were pre-incubated with elastase for 30 min before adding into culture media. At the end of reaction, 5 μl of media were retrieved, denatured and analyzed by Western Blot with anti-V5 tag antibody. Numbers to the left of the blots indicate the position and size (kDa) of molecular mass markers. IB, immunoblot.