[Functional Analyses of HIV-1 Specific Cytotoxic T Lymphocyte Clones]

Human immunodeficiency virus type 1(HIV-1)-specific CD8 cytotoxic T-lymphocytes(CTL)are essential components of the protective immunity against HIV-1infection.However,due to heterogeneous responses of CTL to HIV-1,our general understanding of CTL efficacy in the context of HIV-1infection remains limited. To better understand the factors that determine the potency of HIV-1specific CTL responses, this study directly investigated the relationship between different functional attributes associated with CTL response at the single cell level by using HIV-1specific CTL clones isolated in vitro. Twelve selected HIV-1CTL clones with various HLA restriction and specific antigen epitopes were comprehensively evaluated by several functional assays(e.g., killing capacity, degranulation, production of multiple cytokines and polyfunctionality, as well as the expression of lytic granule components and exhaustion molecules).Our principal findings were that the killing capacity of the CTL response was most closely associated with their degranulation capacity. Additionally, the killing and the degranulation capacity of CTL was associated with the levels and polyfunctionality of the cytokines secreted later. These findings implicate that multiple functional CTL responses are coordinately regulated and determined.