Tumor necrosis factor alpha plays a central role in immune-mediated clearance of adenoviral vectors.

Publication Type	Academic Article
Authors	Elkon K, Liu C, Gall J, Trevejo J, Marino M, Abrahamsen K, Song X, Zhou J, Old L, Crystal R, Falck-Pedersen E
Journal	Proc Natl Acad Sci U S A
Volume	94
Issue	18
Pagination	9814-9
Date Published	09/02/1997
ISSN	0027-8424
Keywords	Adenoviridae, Gene Transfer Techniques, Tumor Necrosis Factor-alpha
Abstract	Adenovirus (Ad) gene transfer vectors are rapidly cleared from infected hepatocytes in mice. To determine which effector mechanisms are responsible for elimination of the Ad vectors, we infected mice that were genetically compromised in immune effector pathways [perforin, Fas, or tumor necrosis factor alpha (TNF-alpha)] with the Ad vector, Ad5-chloramphenicol acetyl transferase (CAT). Mice were sacrificed at 7-60 days postinfection, and the levels of CAT expression in the liver determined by a quantitative enzymatic assay. When the livers of infected mice were harvested 28 days postinfection, the levels of CAT expression revealed that the effectors most important for the elimination of the Ad vector were TNF-alpha > Fas > perforin. TNF-alpha did not have a curative effect on infected hepatocytes, as the administration of TNF-alpha to infected severe combined immunodeficient mice or to infected cultures in vitro had no specific effect on virus persistence. However, TNF-alpha-deficient mice demonstrated a striking reduction in the leukocytic infiltration early on in the infection, suggesting that TNF-alpha deficiency resulted in impaired recruitment of inflammatory cells to the site of inflammation. In addition, the TNF-deficient mice had a significantly reduced humoral immune response to virus infection. These results demonstrate a dominant role of TNF-alpha in elimination of Ad gene transfer vectors. This result is particularly important because viral proteins that disable TNF-alpha function have been removed from most Ad vectors, rendering them highly susceptible to TNF-alpha-mediated elimination.
DOI	10.1073/pnas.94.18.9814
PubMed ID	9275208
PubMed Central ID	PMC23274