Packaging of small molecules into VP1-virus-like particles of the human polyomavirus JC virus

Recombinantly expressed VP1-virus-like particles (VP1-VLP) of human polyoma virus JC virus (JCV) were described recently as a new DNA transporter syste m. It was shown that DNA molecules could be packaged into VP1-VLP during a controlled chemical reassociation/dissociation process. In the present stud y VP1-VLP were studied as carriers for pharmaceutical substances. Propidium iodide (PI) was packaged into VP1-VLP as a reporter molecule. The PI-conta ining VP1-VLP could be detected directly by flow cytometry. The fluorescenc e intensity of the VP1-VLP depended strongly on the initial PI concentratio n. This packaging method is easy to handle and applicable to viruses and VP 1-VLP which can be dissociated and reassociated chemically. (C) 2000 Elsevi er Science B.V. All rights reserved.