摘要
Influenza epidemics and pandemics are constant threats to global public health.Although strategies including vaccines and antiviral drugs have achieved great advances in controlling influenza virus infection,the efficacy of these strategies is limited by the highly frequent mutations in the viral genome and the emergence of drug-resistant strains.Our previous study indicated that boosting the immunity of human Vγ9Vδ2-T cells with the phosphoantigen pamidronate could be a therapeutic strategy to treat seasonal and avian influenza virus infections.However,one notable drawback ofγδ-T cell-based immunotherapy is the rapid exhaustion of proliferation and effector responses due to repeated treatments with phosphoantigens.Here,we found that the expression of CD137 was inducible in Vγ9Vδ2-T cells following antigenic stimulation.CD137^(+)Vγ9Vδ2-T cells displayed more potent antiviral activity against influenza virus than their CD137−counterparts in vitro and in Rag2^(-/-)γc^(-/-)mice.We further demonstrated that CD137 costimulation was essential for Vγ9Vδ2-T cell activation,proliferation,survival and effector functions.In humanized mice reconstituted with human peripheral blood mononuclear cells,CD137 costimulation with a recombinant human CD137L protein boosted the therapeutic effects of pamidronate against influenza virus.Our study provides a novel strategy of targeting CD137 to improve the efficacy of Vγ9Vδ2-T cell-based immunotherapy.
基金
supported in part by the General Research Fund,Research Grants Council of Hong Kong(17115015,17121214,17126317,17122519)
Theme-based Research Scheme from the Research Grants Council of the Hong Kong SAR,China(Project No.T11-705/14N)
Chinese National Natural Science Foundation of China(31570898)
Natural Science Foundation of Guangdong Province,China(2016A030313112).