Pre-existing herpes simplex virus 1 (HSV‐1) immunity decreases, but does not abolish, gene transfer to experimental brain tumors by a HSV‐1 vector. - Herrlinger,U.; Kramm,C.M.; Aboody-Guterman,K.S.; Silver,J.S.; Ikeda,K.; Johnston,K.M.; Pechan,P.A.; Barth,R.F.; Finkelstein,D.; Chiocca,E.A.; Louis,D.N.; Breakefield,X.O. (Gene Ther, 1998)