Animal models for viral infection and cell exhaustion #MMPMID25023622
McGary CS; Silvestri G; Paiardini M
Curr Opin HIV AIDS 2014[Sep]; 9 (5): 492-9 PMID25023622show ga
Purpose of review: Despite eliciting an early antiviral T cell response, HIV-specific T cells are unable to prevent disease progression, partly due to their loss of effector functions, known as T cell exhaustion. Restoring this T cell functionality represents a critical step for regaining immunological control of HIV-1 replication, and may be fundamental for the development of a functional cure for HIV. In this context, the use of animal models is invaluable for evaluating the efficacy and mechanisms of novel therapeutics aimed at reinvigorating T cell functions. Recent findings: While non-human primates continue to be a mainstay for studying HIV pathogenesis and therapies, recent advances in humanized mouse models have improved their ability to recapitulate the features of cell exhaustion during HIV infection. Targeting coinhibitory receptors in HIV- and SIV-infected animals has resulted in viral load reductions, presumably by reinvigorating the effector functions of T cells. Additionally, studies combining PD-1 blockade with suppressive ART provide further support of the use of coinhibitory receptor blockades in restoring T cell function by delaying viral load rebound upon ART interruption. Future in vivo studies should build on recent in vitro data supporting the simultaneous targeting of multiple regulators of cell exhaustion. Summary: In this review, we describe the most recent advances in the use of animal models for the study of cell exhaustion following HIV/SIV infection. These findings suggest that the use of animal models is increasingly critical in translating immunotherapeutics into clinical practice.