Abstract: A transkingdom platform for the delivery of therapeutics to target cells. The system maintains the export and uptake functions of Inv while modifying its targeting away from 1 integrin to other proteins expressed on the surface of target eukaryotic cells (i.e., a cell surface protein) or chemical moieties (i.e., a cell surface chemical moiety) expressed on the surface of a target eukaryotic cell by replacing D4 and D5 of Inv with a binding domain from a heterologous protein via genetic engineering. These heterologous proteins could be derived from bacterial, fungal, animal, or viral genomes. This engineering would result in the construction of a chimeric Inv protein in which D1-D3 (i.e., the non-binding domains) are fused in frame to an alternative binding domain derived from a heterologous protein.