RNA neoantigen vaccines prime long-lived CD8+ T cells in pancreatic cancer
['Sethna, Zachary', 'Greenbaum, Benjamin D.', 'Balachandran, Vinod P.']; Nature; 2025-02-19
『Abstract』A fundamental challenge for cancer vaccines is to generate long-lived functional T cells that are specific for tumour antigens. Here we find that mRNA–lipoplex vaccines against somatic mutation-derived neoantigens may solve this challenge in pancreatic ductal adenocarcinoma (PDAC), a lethal cancer with few mutations. At an extended 3.2-year median follow-up from a phase 1 trial of surgery, atezolizumab (PD-L1 inhibitory antibody), autogene cevumeran (individualized neoantigen vaccine with backbone-optimized uridine mRNA–lipoplex nanoparticles) and modified (m) FOLFIRINOX (chemotherapy) in patients with PDAC, we find that responders with vaccine-induced T cells ( n = 8) have prolonged recurrence-free survival (RFS; median not reached) compared with non-responders without vaccine-induced T cells ( n = 8; median RFS 13.4 months; P = 0.007). In responders, autogene cevumeran induces CD8 T cell clones with an average estimated lifespan of 7.7 years (range 1.5 to roughly 100 years), with approximately 20% of clones having latent multi-decade lifespans that may outlive hosts. Eighty-six percent of clones per patient persist at substantial frequencies approximately 3 years post-vaccination, including clones with high avidity to PDAC neoepitopes. Using PhenoTrack, a novel computational strategy to trace single T cell phenotypes, we uncover that vaccine-induced clones are undetectable in pre-vaccination tissues, and assume a cytotoxic, tissue-resident memory-like T cell state up to three years post-vaccination with preserved neoantigen-specific effector function. Two responders recurred and evidenced fewer vaccine-induced T cells. Furthermore, recurrent PDACs were pruned of vaccine-targeted cancer clones. Thus, in PDAC, autogene cevumeran induces de novo CD8 T cells with multiyear longevity, substantial magnitude and durable effector functions that may delay PDAC recurrence. Adjuvant mRNA–lipoplex neoantigen vaccines may thus solve a pivotal obstacle for cancer vaccination.
『摘要』
癌症疫苗面临的一个根本性挑战是产生针对肿瘤抗原的长效功能性T细胞。本研究发现,针对体细胞突变衍生的新生抗原的mRNA-脂质复合体疫苗可能解决这一挑战,尤其是在胰腺导管腺癌(PDAC)这种突变较少的致命性癌症中。在一项针对PDAC患者的I期试验中,患者接受了手术、阿替利珠单抗(PD-L1抑制抗体)、Autogene cevumeran(采用优化骨架的尿苷mRNA-脂质复合体纳米颗粒制备的个体化新生抗原疫苗)和改良(m)FOLFIRINOX(化疗)联合治疗,在中位随访时间延长至3.2年的情况下,我们发现,有疫苗诱导T细胞产生的应答者(n=8)与无疫苗诱导T细胞产生的非应答者(n=8;中位无复发生存期[RFS]为13.4个月;P=0.007)相比,前者具有更长的无复发生存期(未达到中位RFS)。在应答者中,Autogene cevumeran诱导的CD8 T细胞克隆的平均预期寿命为7.7年(范围1.5年至大约100年),其中大约20%的克隆具有潜在长达数十年的寿命,甚至可能超过宿主的寿命。大约接种疫苗后3年,每位患者体内仍有约86%的克隆以较高频率持续存在,其中包括对PDAC新生表位具有高亲和力的克隆。我们使用PhenoTrack(一种追踪单个T细胞表型的新型计算策略)发现,疫苗诱导的克隆在接种疫苗前的组织中无法检测到,而在接种疫苗后长达3年的时间里,这些克隆表现出细胞毒性、组织驻留记忆样T细胞的状态,并保留了针对新生抗原的特异性效应功能。2例应答者出现复发,且疫苗诱导的T细胞数量减少。此外,复发的PDAC中清除了疫苗靶向的癌细胞克隆。因此,在PDAC中,Autogene cevumeran可诱导新生CD8 T细胞,这些细胞具有多年的寿命、较大的数量和持久的效应功能,可能延缓PDAC的复发。因此,辅助mRNA-脂质复合体新生抗原疫苗可能解决癌症疫苗接种的一个关键障碍。
『总结』
研究发现,针对PDAC的mRNA-脂质复合体新生抗原疫苗Autogene cevumeran可诱导长效、多功能CD8 T细胞,或能延缓癌症复发,为癌症疫苗接种的关键难题提供了解决方案。
『闲叙』