Qiu-Yue Zhang1,2, Xin Zhang1,2, Bin Su1,2, Li-Feng Liu1,2, Xiao-Dong Yang1,2, Bin Tang1,2, Huan Xia3, Ping Ma3, Tong Zhang1,2, Hao Wu1,2. 1. Center for Infectious Diseases, Beijing Youan Hospital, Capital Medical University, Beijing 100069, China. 2. Beijing Key Laboratory for HIV/AIDS Research, Beijing 100069, China. 3. Department of Infectious Diseases, Nankai University Second People's Hospital, Tianjin 300192, China.
Abstract
BACKGROUND: Natural killer (NK) cells play a critical role in suppressing human immunodeficiency virus-1 (HIV-1) infection, but knowledge on whether and how NK cells affect immune reconstitution in HIV-1-infected individuals who receive antiretroviral therapy (ART) is limited. METHODS: We performed a case-control study with 35 healthy individuals and 66 HIV-1-infected patients including 32 immunological non-responders (INRs) with poor CD4+ T-cell recovery (<500 cells/μL after 4 years of ART) and 34 immunological responders (IRs) with improved CD4+ T-cell recovery (>500 cells/μL after 4 years of ART). NK cell phenotype, receptor repertoire, and early activation in INRs and IRs were investigated by flow cytometry. RESULTS: A significantly higher proportion of CD56dimCD16dim/- NK cells was observed in INRs than IRs before ART and after 4 years of ART. The number of CD56dimCD16dim/- NK cells was inversely correlated with CD4+ T-cell counts in INRs before ART (r = -0.344, P = 0.050). The more CD69-expressing NK cells there were, the lower the CD4+ T-cell counts and ΔCD4, and these correlations were observed in INRs after ART (r = -0.416, P = 0.019; r = -0.509, P = 0.003, respectively). Additionally, CD69-expressing CD56dimCD16dim/- NK cells were more abundant in INRs than those in IRs (P = 0.018) after ART, both of which had an inverse association trend towards significance with CD4+ T-cell counts. The expression of the activating receptors NKG2C, NKG2D, and NKp46 on CD56dimCD16dim/- NK cell subsets were higher in IRs than that in INRs after 4 years of ART (all P < 0.01). Strong inverse correlations were observed between CD69 expression and NKG2C, NKG2A-NKG2C+, NKG2D, and NKp46 expression on CD56dimCD16dim/- NK cells in INRs after ART (NKG2C: r = -0.491, P = 0.004; NKG2A-NKG2C+: r = -0.434, P = 0.013; NKG2D: r = -0.405, P = 0.021; NKp46: r = -0.457, P = 0.008, respectively). CONCLUSIONS: INRs had a larger number of CD56dimCD16dim/- NK cells characterized by higher activation levels than did IRs after ART. The increase in the CD56dimCD16dim/- NK cell subset may play an adverse role in immune reconstitution. Further functional studies of CD56dimCD16dim/- NK cells in INRs are urgently needed to inform targeted interventions to optimize immune recovery.
BACKGROUND: Natural killer (NK) cells play a critical role in suppressing humanimmunodeficiency virus-1 (HIV-1) infection, but knowledge on whether and how NK cells affect immune reconstitution in HIV-1-infected individuals who receive antiretroviral therapy (ART) is limited. METHODS: We performed a case-control study with 35 healthy individuals and 66 HIV-1-infectedpatients including 32 immunological non-responders (INRs) with poor CD4+ T-cell recovery (<500 cells/μL after 4 years of ART) and 34 immunological responders (IRs) with improved CD4+ T-cell recovery (>500 cells/μL after 4 years of ART). NK cell phenotype, receptor repertoire, and early activation in INRs and IRs were investigated by flow cytometry. RESULTS: A significantly higher proportion of CD56dimCD16dim/- NK cells was observed in INRs than IRs before ART and after 4 years of ART. The number of CD56dimCD16dim/- NK cells was inversely correlated with CD4+ T-cell counts in INRs before ART (r = -0.344, P = 0.050). The more CD69-expressing NK cells there were, the lower the CD4+ T-cell counts and ΔCD4, and these correlations were observed in INRs after ART (r = -0.416, P = 0.019; r = -0.509, P = 0.003, respectively). Additionally, CD69-expressing CD56dimCD16dim/- NK cells were more abundant in INRs than those in IRs (P = 0.018) after ART, both of which had an inverse association trend towards significance with CD4+ T-cell counts. The expression of the activating receptors NKG2C, NKG2D, and NKp46 on CD56dimCD16dim/- NK cell subsets were higher in IRs than that in INRs after 4 years of ART (all P < 0.01). Strong inverse correlations were observed between CD69 expression and NKG2C, NKG2A-NKG2C+, NKG2D, and NKp46 expression on CD56dimCD16dim/- NK cells in INRs after ART (NKG2C: r = -0.491, P = 0.004; NKG2A-NKG2C+: r = -0.434, P = 0.013; NKG2D: r = -0.405, P = 0.021; NKp46: r = -0.457, P = 0.008, respectively). CONCLUSIONS: INRs had a larger number of CD56dimCD16dim/- NK cells characterized by higher activation levels than did IRs after ART. The increase in the CD56dimCD16dim/- NK cell subset may play an adverse role in immune reconstitution. Further functional studies of CD56dimCD16dim/- NK cells in INRs are urgently needed to inform targeted interventions to optimize immune recovery.