Department of Biological Sciences and CERMO-FC Research Centre, Université du Québec à Montréal (UQAM), Montreal, QC, Canada.
CellCarta, Montreal, QC, Canada.
EBioMedicine. 2024 Sep;107:105274. doi: 10.1016/j.ebiom.2024.105274. Epub 2024 Aug 22.
Despite successful antiretroviral therapy (ART), frequencies and immunological functions of memory CCR6 Th17-polarised CD4 T-cells are not fully restored in people with HIV (PWH). Moreover, long-lived Th17 cells contribute to HIV persistence under ART. However, the molecular mechanisms underlying these observations remain understudied.
mRNA-sequencing was performed using Illumina technology on freshly FACS-sorted memory CCR6CD4 T-cells from successfully ART-treated (ST), elite controllers (EC), and uninfected donors (HD). Gene expression validation was performed by RT-PCR, flow cytometry, and in vitro functional assays.
Decreased Th17 cell frequencies in STs and ECs versus HDs coincided with reduced Th17-lineage cytokine production in vitro. Accordingly, the RORγt/RORC2 repressor NR1D1 was upregulated, while the RORγt/RORC2 inducer Semaphorin 4D was decreased in memory CCR6 T-cells of STs and ECs versus HDs. The presence of HIV-DNA in memory CCR6 T-cells of ST and EC corresponded with the downregulation of HIV restriction factors (SERINC3, KLF3, and RNF125) and HIV inhibitors (tetraspanins), along with increased expression of the HIV-dependency factor MRE11, indicative of higher susceptibility/permissiveness to HIV-1 infection. Furthermore, markers of DNA damage/modification were elevated in memory CCR6 T-cells of STs and ECs versus HDs, in line with their increased activation (CD38/HLA-DR), senescence/exhaustion phenotype (CTLA-4/PD-1/CD57) and their decreased expression of proliferation marker Ki-67.
These results reveal new molecular mechanisms of Th17 cell deficit in ST and EC PWH despite a successful control of HIV-1 replication. This knowledge points to potential therapeutic interventions to limit HIV-1 infection and restore frequencies, effector functions, and senescence/exhaustion in Th17 cells.
This study was funded by the Canadian Institutes of Health Research (CIHR, operating grant MOP 142294, and the Canadian HIV Cure Enterprise [CanCURE 2.0] Team Grant HB2 164064), and in part, by the Réseau SIDA et maladies infectieuses du Fonds de recherche du Québec-Santé (FRQ-S).
尽管抗逆转录病毒疗法（ART）取得了成功，但在 HIV 感染者（PWH）中，记忆性 CCR6 Th17 极化 CD4 T 细胞的频率和免疫功能并未完全恢复。此外，长寿的 Th17 细胞有助于 ART 下 HIV 的持续存在。然而，这些观察结果背后的分子机制仍未得到充分研究。
使用 Illumina 技术对来自成功接受 ART 治疗（ST）、精英控制者（EC）和未感染供体（HD）的新鲜 FACS 分选的记忆性 CCR6CD4 T 细胞进行 mRNA 测序。通过 RT-PCR、流式细胞术和体外功能测定进行基因表达验证。
与 HD 相比，ST 和 EC 中 Th17 细胞频率降低，同时体外 Th17 谱系细胞因子产生减少。相应地，记忆性 CCR6 T 细胞中 RORγt/RORC2 抑制剂 NR1D1 上调，而 RORγt/RORC2 诱导剂 Semaphorin 4D 下调。ST 和 EC 记忆性 CCR6 T 细胞中存在 HIV-DNA，对应于 HIV 限制因子（SERINC3、KLF3 和 RNF125）和 HIV 抑制剂（四跨膜蛋白）下调，以及 HIV 依赖性因子 MRE11 表达增加，表明对 HIV-1 感染的易感性/允许性增加。此外，与 HD 相比，ST 和 EC 记忆性 CCR6 T 细胞中的 DNA 损伤/修饰标志物升高，与它们的激活（CD38/HLA-DR）、衰老/衰竭表型（CTLA-4/PD-1/CD57）以及增殖标志物 Ki-67 的表达减少一致。
这些结果揭示了尽管 HIV-1 复制得到成功控制，但 ST 和 EC PWH 中 Th17 细胞缺陷的新分子机制。这些知识指向潜在的治疗干预措施，以限制 HIV-1 感染并恢复 Th17 细胞的频率、效应功能和衰老/衰竭。
本研究由加拿大卫生研究院（CIHR，运营拨款 MOP 142294，以及加拿大 HIV 治愈企业[CanCURE 2.0]团队拨款 HB2 164064）和魁北克省健康研究基金会的艾滋病和传染病网络（Réseau SIDA et maladies infectieuses du Fonds de recherche du Québec-Santé，FRQ-S）部分资助。
