AIDS-related human cytomegalovirus (HCMV) retinitis causes vision loss and blindness in HIV-immuno- suppressed patients who do not have access to combination antiretroviral therapy (cART) or who fail to adhere to or respond to cART. AIDS-related HCMV retinitis therefore remains a significant ophthalmologic problem worldwide. A critical barrier to progress in advancing our ability to diagnose, prevent, and/or treat AIDS- related HCMV retinitis is an absence of an understanding of the mechanisms by which HCMV, a human ?? herpesvirus, causes retinal tissue destruction during onset and progression of AIDS-related HCMV retinitis. Our goal is to address the problem of AIDS-related HCMV retinitis and the critical barrier to progress by obtaining the information needed to establish the relative role of suppressor of cytokine signaling 1 (SOCS1), SOCS3, necroptosis, and pyroptosis in the pathogenesis of AIDS-related HCMV retinitis. Our central hypothesis is that SOCS1, SOCS3, necroptosis, and pyroptosis individually conspire via different mechanisms to contribute collectively to retinal tissue destruction during the pathogenesis of AIDS-related HCMV retinitis. Our objectives are to use a well-established and clinically relevant animal model of mouse cytomegalovirus (MCMV) retinitis in mice with retrovirus-induced immunosuppression (MAIDS) coupled with in vitro cell culture approaches to (1) obtain the information needed to understand the mechanisms by which SOCS1, SOCS3, necroptosis, and pyroptosis contribute to retinal tissue destruction during evolution of MAIDS-related MCMV retinitis, and (2) use this information to demonstrate that these mechanisms of retinal tissue destruction also operate during AIDS-related HCMV retinitis. These objectives will be met through successful completion of three Specific Aims: (1) test the hypothesis that SOCS1 and SOCS3 proteins play a significant role in the pathogenesis of MAIDS-related MCMV retinitis, (2) test the hypothesis that necroptosis and pyroptosis play a significant role in the pathogenesis of MAIDS-related MCMV retinitis, and (3) test the hypothesis that HCMV stimulates SOCS1, SOCS3, necroptosis, and pyroptosis during AIDS-related HCMV retinitis. Our expected outcomes will include establishing that (1) MCMV promotes retinal tissue destruction through intraocular stimulation of SOCS1 and SOCS3 proteins that interfere with the JAK/STAT pathway and/or toll-like receptor (TLR) signaling to dampen antiviral Type I ??? interferon (IFN) production, (2) MCMV promotes retinal tissue destruction through intraocular stimulation of multiple cell death pathways that include necroptosis and pyroptosis as well as apoptosis, and (3) HCMV promotes retinal tissue destruction during AIDS-related HCMV retinitis via SOCS1, SOCS3, necroptosis, and pyroptosis mechanisms. The impact on the field of AIDS-related HCMV retinitis research will include new information that could directly or indirectly lead to novel therapeutic approaches for management of AIDS-related HCMV retinitis as well as other retinal diseases of herpesvirus origin.
AIDS-related human cytomegalovirus (HCMV) retinitis is a sight-threatening retinal disease that remains a significant ophthalmologic problem worldwide. The proposed project is relevant to public health because its performance will demonstrate for the first time that HCMV causes vision loss and blindness during AIDS and other forms of immunosuppression by (1) intraocular stimulation of Suppressor of Cytokine Signaling (SOCS) proteins that serve to coordinate and regulate antiviral interferon production and the divergent actions of the inflammatory cytokine interleukin-6, and by (2) intraocular stimulation of two very different cell death pathways, necroptosis and pyroptosis, that work in concert with apoptosis to kill retinal cells. The project is relevant to the NEI mission because its performance could lead directly or indirectly to new therapeutic approaches to lessen the vision loss and blindness associated with HCMV retinitis during AIDS and other forms of immunosuppression.
| Alston, Christine I; Dix, Richard D (2017) Murine cytomegalovirus infection of mouse macrophages stimulates early expression of suppressor of cytokine signaling (SOCS)1 and SOCS3. PLoS One 12:e0171812 |
| Alston, Christine I; Dix, Richard D (2017) Reduced frequency of murine cytomegalovirus retinitis in C57BL/6 mice correlates with low levels of suppressor of cytokine signaling (SOCS)1 and SOCS3 expression within the eye during corticosteroid-induced immunosuppression. Cytokine 97:38-41 |
