Journal Article

Distinct immune memory induced by SARS-CoV-2 in convalescent liver transplant recipients

Duan, Binwei, Wang, Yifei, Ouyang, Yabo, Wu, Feng, Sun, Yibo, Li, Guangming, Zhang, Gongming, Sun, Yueyi, Wang, Wenjing, Chen, Zhuangzhuang, Zhang, Yuxuan, Liu, Mengcheng

2025

Overview

The understanding of how the host immune response differs in T-cell phenotype and memory formation during SARS-CoV-2 infection in liver transplant recipients (LTRs) remains limited. LTRs who recovered from COVID-19 infection without prior vaccination represent a unique population for studying immune responses to SARS-CoV-2. Six LTRs with positive neutralizing antibodies (nAb+) and six LTRs with negative nAb (nAb-) were included at 6 months following COVID-19 infection. It was found that nAb+ LTRs had higher anti-RBD IgG titers and greater neutralizing percent inhibition compared to nAb- LTRs. Fifteen T-cell subsets were identified in COVID-19 convalescent LTRs, and it was shown that only terminal effector CD8+ - 3 decreased in the nAb+ group, while elevated IL-10 expression levels were found in the nAb- group. After stimulation with the SARS-CoV-2 XBB spike peptide pool in vitro , it was observed that the nAb+ group exhibited an increase in effector memory CD4+ cells with lower PD-1 expression, a reduction in effector memory CD4+ - 2 cells, and terminal effector CD8+ - 3 cells, while the nAb- group showed high expression of CTLA-4 and IL-10 in terminal effector CD8+ - 3 cells. Four SARS-CoV-2-specific T-cell subsets were identified, with high expression of TNF-α and IFN-γ in terminal effector CD8+ - 1 and terminal effector CD8+ - 2 cells in both groups. Perforin was mainly detected in terminal effector CD8+ - 2 cells in nAb+ LTRs. In addition to these proportional differences, stem cell memory CD4+ cells with higher IL-17A expression and stem cell memory CD8+ cells with higher CTLA-4 expression were also found in nAb- LTRs. These findings suggest that LTRs who developed nAb+ following SARS-CoV-2 infection exhibit stronger T-cell responses, with more robust immune activation and memory recall, compared to nAb- LTRs. This study underscores the importance of understanding T-cell responses during SARS-CoV-2 recovery for guiding vaccination strategies and managing immunity in LTRs.

• Publisher: Frontiers Media SA
• Subject: Antibodies / CD4 antigen / CD8 antigen / COVID-19 / COVID-19 vaccines / CTLA-4 protein / Cytokines / Effector cells / Immune response / Immunity (Disease) / Immunocompetence / Immunoglobulin G / Immunological memory / Infections / Interleukin 10 / Liver transplantation / Liver transplants / Lymphocytes / Lymphocytes T / PD-1 protein / Perforin / Phenotypes / Severe acute respiratory syndrome coronavirus 2 / Stem cells / Tumor necrosis factor-α / Vaccination / γ-Interferon