Abstract：
Immunosuppression is a common feature of esophageal adenocarcinoma (EAC) and has been linked to poor overall survival (OS). We hypothesized that upstream factors might negatively influence CD3 levels and T cell activity, thus promoting immunosuppression and worse survival. We used clinical data and patient samples of those who progressed from Barrett\'s to dysplasia to EAC, investigated gene (RNA-Seq) and protein (tissue microarray) expression, and performed cell biology studies to delineate a pathway impacting CD3 protein stability that might influence EAC outcome. We showed that the loss of both CD3-ε expression and CD3+ T cell number correlated with worse OS in EAC. The gene related to anergy in lymphocytes isoform 1 (GRAIL1), which is the prominent isoform in EACs, degraded (ε, γ, δ) CD3s and inactivated T cells. In contrast, isoform 2 (GRAIL2), which is reduced in EACs, stabilized CD3s. Further, GRAIL1-mediated CD3 degradation was facilitated by interferon-stimulated gene 15 (ISG15), a ubiquitin-like protein. Consequently, the overexpression of a ligase-dead GRAIL1, ISG15 knockdown, or the overexpression of a conjugation-defective ISG15-leucine-arginine-glycine-glycine mutant could increase CD3 levels. Together, we identified an ISG15/GRAIL1/mutant p53 amplification loop negatively influencing CD3 levels and T cell activity, thus promoting immunosuppression in EAC.
摘要：
免疫抑制是食管腺癌（EAC）的常见特征，并且与不良的总体生存率（OS）有关。我们假设上游因素可能会对CD3水平和T细胞活性产生负面影响，从而促进免疫抑制和更差的生存。我们使用了从Barrett（BE）到发育不良再到EAC的患者的临床数据和患者样本，调查基因（RNAseq），蛋白质（组织微阵列）表达，并进行细胞生物学研究，以描绘影响可能影响EAC结果的CD3蛋白稳定性的途径。我们表明，CD3-ε表达和CD3T细胞数量的损失与EAC中较差的OS相关。GRAIL（与淋巴细胞无反应性相关的基因）同工型1（GRAIL1），这是EAC中突出的同工型，降解(ε，γ,δ)CD3s并使T细胞失活。相比之下,同工型2(GRAIL2)，在EAC中减少，稳定CD3s。Further,干扰素刺激基因15（ISG15）促进了GRAIL1介导的CD3降解，泛素样蛋白质.因此,连接酶死亡GRAIL1的过表达，ISG15敲低，或缀合缺陷型ISG15-LRAA突变体的过表达可以增加CD3水平。一起,我们发现ISG15→GRAIL1→突变型p53扩增环对CD3水平和T细胞活性有负面影响，从而促进EAC中的免疫抑制。
