Adenoviruses have been recently recognized as a highly efficient system for gene delivery to various tissues. The ability of replication-defective recombinant adenovirus to transfer the lacZ reporter gene encoding beta-galactosidase to nerve cells in various brain structures has been demonstrated. Here, on the continuation of these studies, we present evidence that the adenovirus can be transported in a retrograde manner to nerve cell bodies from axonal terminals. This method may be of great value for infecting selected subsets of specific neurons for either anatomo-functional studies or even therapeutic purposes.