Figure 3.

Isolation of the low molecular weight growth factor from bovine vitreous. a, b, Reversed-phase HPLC. The low molecular weight factor from bovine vitreous was concentrated, extracted into 95% ethanol, and subjected to HPLC on a C-18 reversed-phase column. Axon-promoting activity eluted early. c, d, On a G-10 Sephadex gel-filtration column, the axon-promoting activity eluted as a coherent peak. e, f, Normal-phase chromatography. Fractions containing the axon-promoting activity from the gel-filtration column were pooled and separated on an LC-NH₂ normal-phase HPLC column. Bioassays, performed on goldfish RGCs, show that the axon-promoting activity elutes later than most other components (arrows).