Biological and immunological properties of nerve growth factor from snake venoms.

Homogeneous preparation of nerve growth factor (NGF) was isolated in purity by two steps HPLC fractionation from venoms of snakes belonging to the major families: Crotalidae, Elapidae, and Viperidae. Biological activity of NGF was tested on PC12 cells for neurite outgrowth and molecular weights were determined by PAGE. Antisera raised against NGFs in Balb/C mice. Immunological cross reactivity for antisera was assayed by ELISA and immunoprecipitin tests. HPLC profiles for the venoms from the species belonging to the same family were identical. The biological and immunological properties of NGFs from different species of snake belonging to the same family were also found to be identical. However, NGFs of venoms from different families of snakes showed differences in properties. Neurite outgrowth on PC12 cells due to NGF from the family Elapidae, especially the cobra species, was greater than NGF from the venoms of Crotalidae and Viperidae, with the exception of N. n. nivea which showed poor activity and C. polystictus of Crotalidae family having very good activity.