Fassina, Gianfrancoa,b; Buffa, Annac; Benelli, Robertoa,c; Varnier, Oliviero E.d; Noonan, Douglas M.a; Albini, Adrianaa
aIstituto Nazionale per la Ricerca sul Cancro, Genoa, Italy; bCentro di Studio per la Neurofisiologia Cerebrale, Consiglio Nazionale delle Ricerche, Genoa, Italy; cCentro per le Biotecnologie Avanzate, Genoa, Italy; and dInstitute of Microbiology, School of Medicine, University of Genoa, Italy.
Sponsorship: This work was partly supported by ISS grant 3rd Programma Nazionale di Ricerca sull'AIDS.
Received: 10 August 2001;
revised: 30 October 2001; accepted: 14 November 2001.