First Author | Robertson SJ | Year | 2008 |
Journal | J Immunol | Volume | 180 |
Issue | 8 | Pages | 5267-74 |
PubMed ID | 18390707 | Mgi Jnum | J:134243 |
Mgi Id | MGI:3785184 | Doi | 10.4049/jimmunol.180.8.5267 |
Citation | Robertson SJ, et al. (2008) CD137 costimulation of CD8+ T cells confers resistance to suppression by virus-induced regulatory T cells. J Immunol 180(8):5267-74 |
abstractText | Chronic viral infections cause high levels of morbidity and mortality worldwide, making the development of effective therapies a high priority for improving human health. We have used mice infected with Friend virus as a model to study immunotherapeutic approaches to the cure of chronic retroviral infections. In chronic Friend virus infections CD4(+) T regulatory (Treg) cells suppress CD8(+) T cell effector functions critical for virus clearance. In this study, we demonstrate that immunotherapy with a combination of agonistic anti-CD137 Ab and virus-specific, TCR-transgenic CD8(+) T cells produced greater than 99% reductions of virus levels within 2 wk. In vitro studies indicated that the CD137-specific Ab rendered the CD8(+) T cells resistant to Treg cell-mediated suppression with no direct effect on the suppressive function of the Treg cells. By 2 weeks after transfer, the adoptively transferred CD8(+) T cells were lost, likely due to activation-induced cell death. The highly focused immunological pressure placed on the virus by the single specificity CD8(+) T cells led to the appearance of escape variants, indicating that broader epitope specificity will be required for long-term virus control. However, the results demonstrate a potent strategy to potentiate the function of CD8(+) T cells in the context of immunosuppressive Treg cells. |