Affiliation: | IRIS, Immunobiological Research Institute Siena, via Fiorentina 1, 53100 Siena, Italy. Tel. (577) 243414;Fax (577) 243564.;Department of Microbiology and Immunology, Uniformed Services, University of the Health Sciences. 4301 Jones Bridge Road, Bethesda. Maryland 20814. USA. Tel. (301) 295 3405: Fax (301) 295 1545. |