BALTIMORE, MD--(Marketwire - June 27, 2008) - A new study suggests for the first time that human herpesvirus 6 (HHV-6) infects and persists in a dormant state in endothelial cells, the cells lining blood vessels, and causes these cells to lose their ability to grow, to form new blood vessels, and to take part in healing processes. This finding was announced at the 6th International Conference for HHV-6 & 7 by a team of Italian researchers, professors Arnaldo Caruso of the University of Brescia and Dario Di Luca of the University of Ferrara.