Human embryonic kidney 293 cells contain the E1 region E1-E3 regions, in an unpackagable form. Investigation of of adenovirus type 5, and thus sustain, through transcompthe reason for massive cell death after cotransfection led lementation, the production of recombinant E1-deleted us to determine that 293 cells express the FasL receptor, adenovirus vectors. During attempts to produce recombiFas-Apo1 (CD95), and respond with apoptosis to the nant adenovirus expressing the apoptosis-inducing molcross-linking of Fas-Apo1 with either IgM monoclonal antiecule Fas ligand (FasL) under the control of a very strong bodies or FasL. Therefore, we decided to generate adenotruncated major immediate-early human cytomegalovirus viral vectors expressing FasL under the control of tissue-(MIEhCMV) promoter, we discovered that 293 cells were specific and/or -inducible promoter elements. Our findings not surviving the initial cotransfection with a shuttle plasmid can explain difficulties several groups have had in generatencoding the mouse FasL; and pJM17, a plasmid containing recombinant adenoviral vectors expressing FasL using ing the genome of adenovirus type 5 with deletions in the 293 cells, as well as the lower titres reported.

We have designed a system in which to test gene transferWe encountered a distinctive staining of cells arranged in into gut neurons consisting of an organ culture of neonatal two concentric circles corresponding in location to the rat small intestine. The tissue was exposed to herpes simmyenteric and submucosal plexuses. Cells in these areas plex-and adenovirus-derived vectors: (1) a temperaturewere of similar size and morphology to neonatal enteric sensitive herpes simplex virus-1 (HSV1) vector (tsK-␤gal) neurons, as visualized by NADPH-diaphorase histochemicontaining the lacZ gene encoding ␤-galactosidase (␤-gal), stry and immunocytochemical staining with antibodies to under the transcriptional control of the HSV1 immediatethe neuronally expressed proteins PGP 9.5, or neurofilaearly 3 (IE3) promoter; (2) RAd35, an E1 − /E3 − replicationments. Double labelling with antibodies recognizing neurodeficient adenovirus expressing lacZ under the control of filaments and ␤-galactosidase revealed that most cells a truncated HCMV major IE promoter; and (3) RAd122, an infected by tsK were neurons, while the RAd35 and 122 E1 − /E3− replication-deficient adenovirus expressing the vectors only infected non-neuronal cells. We thus demonlacZ under the control of the RSV LTR. Forty-eight hours strate that both HSV1-and adenovirus-derived vectors can after the vector was added to the organ culture, we be used to transfer genes to the gut in vitro, but they transdetected ␤-gal using immunohistochemistry or X-gal histoduce different populations of target cells. chemistry in tissue sections examined by light microscopy.