I am using a polyclonal antibody to GFAP to determine if GFAP is
expressed in P19 cells during differentiation. However, I detect a
major polypeptide of approximately 58 kDa using western blot. P19 are
of mouse origin. I used a positive control from rat primary astrocytes
which gives a major size of 50 kDa. I am wondering if the 58 kDa
protein that I detect is GFP or a cross reaction with another protein...