Monceaux, V. | bioRxiv Science

bioRxiv2020

Anti-apoptotic clone 11 derived peptides induce in vitro death of CD4+ T cells susceptible to HIV-1 infection

HIV-1 successfully establishes long-term infection in its target cells despite viral cytotoxic effects. We have recently shown that cell metabolism is an important factor driving CD4+ T-cell susceptibility to HIV-1 and the survival of infected cells. We show here that expression of anti-apoptotic clone 11 (AAC-11), an anti-apoptotic factor upregulated in many cancers, increased with progressive CD4+ T cell memory differentiation in association with the expression of cell cycle, activation and metabolism genes and correlated with susceptibility to HIV-1 infection. Synthetic peptides based on the LZ domain sequence of AAC-11, responsible for its interaction with molecular partners, were previously shown to be cytotoxic to cancer cells. Here we observed that these peptides also blocked HIV-1 infection by inducing cell death of HIV-1 susceptible primary CD4+ T-cells across all T-cell subsets. The peptides targeted metabolically active cells and had the greatest effect on effector and transitional CD4+ T cell memory subsets. Our results suggest that AAC-11 survival pathway is potentially involved in the survival of HIV-1 infectable cells and provide a proof of principle that some cellular characteristics can be targeted to eliminate the cells offering the best conditions to sustain HIV-1 replication. IMPORTANCEAlthough antiretroviral treatment efficiently blocks HIV multiplication, it cannot eliminate the cells already carrying integrated proviruses. In the search for a HIV cure the identification of new potential targets to selectively eliminate infected cells is of the outmost importance. We show here that peptides derived from the anti-apoptotic clone 11 (AAC-11), which expression levels correlated with susceptibility to HIV-1 infection of CD4+ T-cells, induced cytotoxicity in CD4+ T-cells showing the highest levels of activation and metabolic activity, conditions known to favor HIV-1 infection. Accordingly, CD4+ T-cells that survived the cytotoxic action of the AAC-11 peptides were resistant to HIV-1 replication. Our results identify a new potential molecular pathway to target HIV-1 infection.

microbiology↗

bioRxiv2019

Optimal maturation of the SIV-specific CD8+ T-cell response after primary infection is associated with natural control of SIV. ANRS SIC study

Highly efficient virus-specific CD8+ T-cells are associated with immune control of HIV infection, but it remains unclear how these cells are generated and maintained over time. We used a macaque model of spontaneous control of SIVmac251 infection to monitor the development and evolution of potent antiviral CD8+ T-cell responses. SIV-specific CD8+ T-cells emerged during primary infection in all animals. However, the ability of CD8+ T cells to suppress SIV replication was low in early stages but increased after a period of maturation, temporally linked with the establishment of sustained low-level viremia in controller macaques. SIV-specific CD8+ T-cells with a central memory phenotype expressed higher levels of survival markers in controllers versus non-controllers. In contrast, a persistently skewed differentiation phenotype was observed among central memory SIV-specific CD8+ T-cells in non-controllers since primary infection, typified by relatively high expression levels of T-bet. Collectively, these data show that the phenotype of SIV-specific CD8+ T-cells defined early after SIV infection favor the gain of antiviral potency as a function of time in controllers, whereas SIV-specific CD8+ T-cell responses in non-controllers fail to gain antiviral potency due to early defects imprinted in the central memory pool.

immunology↗