Neoantigen burden and CD8 T cell infiltrate are associated with clinical outcome in pancreatic ductal adenocarcinoma (PDAC). A shortcoming of many genetic models of PDAC is the lack of neoantigen burden and limited T cell infiltrate. The goal of the present study was to develop clinically relevant models of PDAC by inducing cancer neoantigens in KP2, a cell line derived from the KPC model of PDAC. KP2 was treated with oxaliplatin and olaparib (OXPARPi), and a resistant cell line was subsequently cloned to generate multiple genetically distinct cell lines (KP2-OXPARPi clones). Clones A and E are sensitive to immune checkpoint inhibition (ICI), exhibit relatively high T cell infiltration, and have significant upregulation of genes involved in antigen presentation, T cell differentiation, and chemokine signaling pathways. Clone B is resistant to ICI and is similar to the parental KP2 cell line in terms of relatively low T cell infiltration and no upregulation of genes involved in the pathways noted above. Tumor/normal exome sequencing and in silico neoantigen prediction confirms successful generation of cancer neoantigens in the KP2-OXPARPi clones and the relative lack of cancer neoantigens in the parental KP2 cell line. Neoantigen vaccine experiments demonstrate that a subset of candidate neoantigens are immunogenic and neoantigen synthetic long peptide vaccines can restrain Clone E tumor growth. Compared to existing models, the KP2-OXPARPi clones better capture the diverse immunobiology of human PDAC and may serve as models for future investigations in cancer immunotherapies and strategies targeting cancer neoantigens in PDAC.

新抗原负荷和 CD8 T 细胞浸润与胰腺​​导管腺癌 (PDAC) 的临床结果相关。许多 PDAC 遗传模型的缺点是缺乏新抗原负荷和有限的 T 细胞浸润。本研究的目标是通过在 KP2（一种源自 PDAC KPC 模型的细胞系）中诱导癌症新抗原来开发临床相关的 PDAC 模型。用奥沙利铂和奥拉帕尼 (OXPARPi) 处理 KP2，随后克隆耐药细胞系以产生多个遗传上不同的细胞系（KP2-OXPARPi 克隆）。克隆 A 和 E 对免疫检查点抑制 (ICI) 敏感，表现出相对较高的 T 细胞浸润，并且参与抗原呈递、T 细胞分化和趋化因子信号传导途径的基因显着上调。克隆 B 对 ICI 具有抗性，并且与亲本 KP2 细胞系相似，T 细胞浸润相对较低，并且上述途径中涉及的基因没有上调。肿瘤/正常外显子组测序和计算机新抗原预测证实了 KP2-OXPARPi 克隆中癌症新抗原的成功生成以及亲代 KP2 细胞系中癌症新抗原的相对缺乏。新抗原疫苗实验表明，候选新抗原的一部分具有免疫原性，新抗原合成长肽疫苗可以抑制克隆E肿瘤的生长。与现有模型相比，KP2-OXPARPi 克隆更好地捕获了人类 PDAC 的多样化免疫生物学，并可作为未来研究癌症免疫疗法和针对 PDAC 中癌症新抗原的策略的模型。