Intracerebral transplantation of dissociated central nervous system tissue suspensions: use of phaseolus vulgaris leucoagglutinin as a cell marker.

Successfully transplanted neurons and their sprouting processes were demonstrated by Phaseolus vulgaris leucoagglutinin (PHA) marking. PHA is transported anterogradely and readily reveals the post-transplantation growth of the neuronal processes. Suspensions of fetal central nervous tissue, prepared by dissociation of embryonic rat brain, were marked with PHA and then transplanted into the striatum of nonimmunosuppressed young adult rats. At various intervals thereafter (1 day, 2 days, 1 week, 2 weeks, 1 month, and 2 months), the animals were sacrificed for histological examination with PHA and tyrosine hydroxylase (TH) immunohistochemistry. Up to 2 weeks after transplantation, PHA immunohistochemistry was capable of demonstrating grafted neurons and their presumably regenerated neuronal processes. However, at periods 1 month or longer after transplantation, PHA immunohistochemistry was unreliable. Thus, the PHA marking method has limitations in terms of its retention period, when applied to the intracerebral transplantation of dissociated cell suspensions. Nevertheless, the method presented here can be utilized to study neuronal regeneration as well as the relationship between transplanted neurons and the host tissue.