There are, strictly speaking (some typographer correct me please if I am wrong), no italic sans serif fonts, but only slanted sans serif fonts.
I believe Adobe Myriad claims a "true italic"; the letterforms are sans versions of standard italic letterforms, rather than obliques of the upright forms.
-- Curtis Clark http://www.csupomona.edu/~jcclark/ Mockingbird Font Works http://www.mockfont.com/