High-efficiency gene transfer employing adenovirus-polylysine-DNA complexes.

Abstract

Gene transfer may be accomplished via the receptor-mediated endocytosis pathway employing molecular conjugate vectors. These synthetic agents consist of two covalently linked functional components: a DNA-binding domain and a domain that is a ligand for a cell surface receptor. Recognition of the ligand by its appropriate cell surface receptor allows cellular internalization of the complex via receptor-mediated endocytosis. Since conjugates are limited because they lack a specific mechanism to accomplish cell vesicle escape, and since adenoviruses possess such a mechanism, we derived conjugates that incorporate adenovirus into their functional design. The adenovirus-polylysine conjugates mediated high-efficiency gene transfer. In this configuration, the viral moiety functions both as an endosomolysis agent and also as the ligand domain of the conjugate. To determine whether the adenovirus component of the conjugate could function exclusively in the former capacity, combination conjugates were constructed containing an alternative ligand in conjugation with an incorporated adenovirus. Internalization of these conjugates via the receptor for the alternative ligand in cells lacking adenovirus receptors demonstrated that the adenovirus moiety could function to enhance conjugate entry in this context. Thus, it is possible to design highly efficient molecular conjugate vectors that possess specific and distinct mechanisms to accomplish cellular internalization and cell vesicle escape.