TNF-α Receptor Signaling and IL-10 Gene Therapy Regulate the Innate and Humoral Immune Responses to Recombinant Adenovirus in the Lung

Abstract

Recombinant adenovirus-mediated gene therapy has demonstrated great promise for the delivery of genes to the pulmonary epithelium. However, dose-dependent inflammation and local immune responses abbreviate transgene expression. The purpose of these studies was to determine the role of TNF-α and individual TNF receptor signaling to adenovirus clearance and immune responses, and whether coexpression of human IL-10 could reduce inflammation and extend the duration of transgene expression in the lung. β-Galactosidase expression in mice receiving intratracheal instillation of Adv/β-gal (adenovirus construct expressing β-galactosidase) was transient (less than 14 days), but a significant early increase of β-galactosidase expression was seen in mice lacking either or both TNF-α receptors. Absence of TNF-α or the p55 receptor significantly attenuated the Ab response to both adenovirus and β-galactosidase. Human IL-10 expression in the lung suppressed local TNF-α production following AdV/hIL-10 (adenovirus construct expressing human IL-10) delivery, but did not lead to increased or prolonged transgene expression when coexpressed with β-galactosidase. Expression of human IL-10 following AdV/hIL-10 instillation extended at least 14 days, was nonimmunogenic, and suppressed the development of neutralizing Abs against adenoviral proteins as well as against human IL-10. We conclude that TNF-α signaling through both the p55 and p75 receptor plays important roles in the clearance of adenoviral vectors and the magnitude of the humoral immune response. Additionally, although coexpression of human IL-10 with β-galactosidase had only modest effects on transgene expression, we demonstrate that AdV/hIL-10 is well tolerated, has extended expression compared with β-galactosidase, and is nonimmunogenic in the lung.

Dose-dependent improvements in outcome with adenoviral expression of interleukin-10 in a murine model of multisystem organ failure

“…These results confirmed our earlier findings in healthy mice that adenoviral expression of viral IL-10 was associated with prolonged and more specific local expression compared to human IL-10. 11,12 In the present report, we confirmed that at a dose of 10 7 , survival after induction of zymosan lung injury with pre-treatment with buffer or various adenoviral vectors at 10 7 particles). As seen previously, 13 the effects of adenoviral recombinants expressing viral IL-10 were markedly better than those seen with human IL-10, although both treatments improved outcome significantly.…”

“…We and others have shown that the intratracheal instillation of adenovirus induces a local inflammatory response characterized by production of TNF-a. 11 Interruption of TNF signaling has been shown to attenuate the innate and acquired immune responses to the adenovirus recombinants directly. 23,24 One explanation may be that the increased adenovirus load heightened the inflammatory response to the zymosan administration, and exacerbated the lung injury.…”

“…Bioactive TNF-a was measured in serum and lung homogenates with the TNF-a a-sensitive WEHI 164 clone 13 murine fibrosarcoma cell line. 11 A standard curve was generated with human TNF-a. The sensitivity of the assay was 5-25 pg/ml for serum and 75-375 pg/g wet weight for lung.…”

“…In fact, adenovirus recombinants are currently in clinical trials as a means to ectopically express growth factors and cytokines for targeted treatment of cancer, rheumatoid arthritis, and chronic wounds. [8][9][10] We have reported that intratracheal instillation of an E1,E3-deleted adenovirus expressing interleukin-10 (IL-10) can generate local production of IL-10 11,12 and can modify outcome in a number of chronic and acute inflammatory processes, including sepsis and acute pancreatitis. 13 Similar results were not seen when the same recombinants were given systemically.…”

IL-10 gene therapy prevents TNBS-induced colitis

“…29 Finally, in this study we did not assess the host anti-adenovirus response, which may shorten the duration of transgenic IL-10 expression. However, in other animal models, we 23 and others 30,31 have shown that the delivery of immunoregulatory genes is able to suppress the development of antiadenoviral antibodies resulting in extended transgene expression.…”