Monoclonal antibodies against Vipera lebetina venom nerve growth factor cross-react with other snake venom nerve growth factors.

Nerve growth factor (NGF) was isolated from the venom of Vipera lebetina and was purified to homogeneity as judged by SDS gel electrophoresis. The biologically active NGF was used to immunize BALB/c mouse, and the spleen cells from immunized mouse were fused with mouse PAI myeloma cells. Forty-seven hybrid cell lines, secreting monoclonal antibodies to V. lebetina NGF, were isolated and nine of them purified from ascitic fluids. The isolated antibodies define two partially overlapping epitopes of the V. lebetina NGF which are not involved in the biological activity of the molecule. Both epitopes are also present on the beta-NGF from the mouse salivary gland and on the NGFs from the following snake venoms: V. lebetina, V, ursini, V, berus berus, Echis carinatus, Bungarus caeruleus, Agkistrodon halys, Naja naja oxiana, Naja naja atra and Naja naja, but not on the bovine seminal plasma NGF. The mol. wts of the NGFs in these snake venoms were determined by Western immunoblot with monoclonal antibodies. The mol. wts of the NGFs from V. ursini (37,000), E. carinatus (36,000, 44,000) and A. halys (29,000) were determined for the first time.