• Junyan Jin, Xiuwen Wang, Yongzheng Li, Xiaodong Yang, Hu Wang, Xiaoxu Han, Jin Sun, Zhenglai Ma, Junyi Duan, Guanghui Zhang, Tao Huang, Tong Zhang, Hao Wu, Xin Zhang, and Bin Su.
• Beijing Key Laboratory for HIV/AIDS Research, Sino-French Joint Laboratory for Research on Humoral Immune Response to HIV Infection, Clinical and Research Center for Infectious Diseases, Beijing Youan Hospital, Capital Medical University, Beijing 100069, China.
• Chin. Med. J. 2023 Dec 20; 136 (24): 293829472938-2947.

BackgroundT-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibition motif domains (TIGIT), an inhibitory receptor expressed on T cells, plays a dysfunctional role in antiviral infection and antitumor activity. However, it is unknown whether TIGIT expression on T cells influences the immunological effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) inactivated vaccines.MethodsForty-five people living with HIV (PLWH) on antiretroviral therapy (ART) for more than two years and 31 healthy controls (HCs), all received a third dose of a SARS-CoV-2 inactivated vaccine, were enrolled in this study. The amounts, activation, proportion of cell subsets, and magnitude of the SARS-CoV-2-specific immune response of TIGIT + CD4 + and TIGIT + CD8 + T cells were investigated before the third dose but 6 months after the second vaccine dose (0W), 4 weeks (4W) and 12 weeks (12W) after the third dose.ResultsCompared to that in HCs, the frequency of TIGIT + CD8 + T cells in the peripheral blood of PLWH increased at 12W after the third dose of the inactivated vaccine, and the immune activation of TIGIT + CD8 + T cells also increased. A decrease in the ratio of both T naïve (T N ) and central memory (T CM ) cells among TIGIT + CD8 + T cells and an increase in the ratio of the effector memory (T EM ) subpopulation were observed at 12W in PLWH. Interestingly, particularly at 12W, a higher proportion of TIGIT + CD8 + T cells expressing CD137 and CD69 simultaneously was observed in HCs than in PLWH based on the activation-induced marker assay. Compared with 0W, SARS-CoV-2-specific TIGIT + CD8 + T-cell responses in PLWH were not enhanced at 12W but were enhanced in HCs. Additionally, at all time points, the SARS-CoV-2-specific responses of TIGIT + CD8 + T cells in PLWH were significantly weaker than those of TIGIT - CD8 + T cells. However, in HCs, the difference in the SARS-CoV-2-specific responses induced between TIGIT + CD8 + T cells and TIGIT - CD8 + T cells was insignificant at 4W and 12W, except at 0W.ConclusionsTIGIT expression on CD8 + T cells may hinder the T-cell immune response to a booster dose of an inactivated SARS-CoV-2 vaccine, suggesting weakened resistance to SARS-CoV-2 infection, especially in PLWH. Furthermore, TIGIT may be used as a potential target to increase the production of SARS-CoV-2-specific CD8 + T cells, thereby enhancing the effectiveness of vaccination.Copyright © 2023 The Chinese Medical Association, produced by Wolters Kluwer, Inc. under the CC-BY-NC-ND license.

23 keywords...

hide…