TARGETING TOXINS TO NEURAL ANTIGENS AND RECEPTORS

Immunotoxins have been used to study the targeting of biologically act ive substances at neurons in vivo and to make experimental neural lesi ons. OX7-saporin, directed against Thy 1, destroys airy neuron. 192 Ig G-saporin, directed against the ('low affinity) neurotrophin receptor (p75(NTR)), selectively destroys neurons expressing this receptor (sym pathetic, sensory, cholinergic basal forebrain, cerebellar Purkinje). Anti-D beta H-saporin, directed against dopamine beta-hydroxylase, the enzyme that converts dopamine to norepinephrine, selectively destroys noradrenergic neurons (sympathetic, CNS). These agents show that seve ral types of neural antigens may prove useful in treating pain, and an ti-D beta H-saporin may be active against pheochromocytoma or neurobla stoma.