1988 mol cell biol 7 349 1988 samulski et al 1989 j virol 63 3822 3828 u s pat no 5 173 414 wo 95 13365 and corresponding u s pat no 5 658 776 wo 95 13392 wo 96 17947 pct us98 18600 wo 97 09441 pct us96 14423 wo 97 08298 pct us96 13872 wo 97 21825 pct us96 20777 wo 97 06243 pct fr96 01064 wo 99 11764 perrin et al 1995 vaccine 13 1244 1250 paul et al 1993 human gene therapy 4 609 615 clark et al 1996 gene therapy 3 1124 1132 u s pat no 5 786 211 u s pat no 5 871 982 and u s pat no 6 258 595 the foregoing documents are hereby incorporated by reference in their entirety herein with particular emphasis on those sections of the documents relating to raav production the invention thus provides packaging cells that produce infectious raav in one embodiment packaging cells may be stably transformed cancer cells such as hela cells 293 cells and perc 6 cells a cognate 293 line in another embodiment packaging cells are cells that are not transformed cancer cells such as low passage 293 cells human fetal kidney cells transformed.