The identification of novel biomarkers and therapeutic targets in advanced cancer is critical for improving cancer diagnosis and therapeutics. Survivin (SV) is highly expressed predominantly in most cancer cells and tissues but is absent or undetectable in terminally differentiated normal adult tissues. Therefore, it functions as an almost universal tumor antigen. Peptides are short chains of amino acids linked by peptide bonds. To obtain novel SV decamers that are able to induce SV-specific cytotoxic T lymphocytes (CTLs) with a higher cytotoxic efficiency against cancer cells, major histocompatibility complex (MHC) peptide binding algorithms were conducted to predict nine modified SV₉₅ decamers (from SV_95–2 to SV_95–10) based on the natural SV_95–104 peptide sequence of ELTLGEFLKL (here defined as SV_95–1). The fluorescent density of each SV₉₅ peptide was determined by a MHC stability assay, followed by the generation of SV₉₅-specific CTLs with each SV₉₅ peptide (from SV_95–1 to SV_95–10) and human dendritic cells (DCs) loaded with Poly(lactic-co-glycolic) acid (PLGA) nanoparticles encapsulated with SV₉₅ peptide. Finally, IFN-γ ELISpot and CytoTox 96^® Non-Radioactive Cytotoxicity Assays were employed to verify their cytotoxic efficiency of the SV₉₅-specific CTLs generated with the corresponding artificial antigen presenting cells (aAPCs) containing SV₉₅ (SV_95–1 to SV_95–10) peptide. Furthermore, the cytotoxicity of the SV₉₅ specific CTLs generated with nine mutated SV₉₅ peptides was compared to the one generated with natural SV_95–1 peptide and TIL2080 cells. The results indicated that the HLA-A2-restricted mutated SV₉₅ epitope decamers (SV_95–6 and SV_95–7) showed significant higher binding ability compared to natural peptide SV_95–1 in MHC stability assay. More importantly, SV_95–specific CTLs with higher cytotoxicity were successfully induced with both SV_95–6 and SV_95–7 peptides, which significantly eliminated target cells (not only SV_95–1 peptide pulsed T2 cells, but also both HLA-A2 and SV positive cancer cells) when compared to those generated with natural SV_95–1 peptide and TIL2080 cells. These findings suggest that the SV_95–6 and SV_95–7 peptides are two novel HLA-A2-restricted CTL epitopes and may be useful for the immunotherapy for patients with survivin expressing cancer.

晚期癌症中新型生物标志物和治疗靶标的鉴定对于改善癌症诊断和治疗至关重要。Survivin（SV）主要在大多数癌细胞和组织中高表达，但在终末分化的正常成人组织中却不存在或无法检测到。因此，它起着几乎通用的肿瘤抗原的作用。肽是通过肽键连接的氨基酸的短链。为了获得能够诱导SV特异性细胞毒性T淋巴细胞（CTL）对癌细胞具有更高细胞毒性效率的新型SV十聚体，进行了主要的组织相容性复合物（MHC）肽结合算法来预测九种修饰的SV ₉₅十聚体（来自SV _{95 –2}至SV _95–10），基于自然SV_95-104 ELTLGEFLKL的肽序列（在此定义为SV _95-1）。通过MHC稳定性测定来确定每种SV ₉₅肽的荧光密度，然后用每种SV ₉₅肽（从SV _95–1到SV _95–10）和人树突状细胞（DC）生成SV ₉₅特异性CTL。装满Poly（lactic-合作-乙醇酸（PLGA）纳米颗粒包裹有SV ₉₅肽。最后，IFN-γ酶联免疫斑点法和CytoTox 96 ^®非放射性细胞毒性测定法被雇用来验证他们的SV的细胞毒性效率₉₅与相应的人工抗原提呈细胞（AAPCS）含有SV产生的特异性的CTL ₉₅（SV _95-1至SV _95–10）肽。此外，将九种突变的SV ₉₅肽产生的SV ₉₅特异性CTL的细胞毒性与天然SV _95-1肽和TIL2080产生的一种细胞毒性进行了比较。细胞。结果表明，在MHC稳定性检测中，与天然肽SV _95-1相比，HLA-A2限制性突变的SV ₉₅表位十聚体（SV _95-6和SV _95-7）显示出更高的结合能力。更重要的是，SV _95-6和SV _95-7肽成功诱导了具有更高细胞毒性的SV ₉₅特异性CTL ，从而显着消除了靶细胞（不仅是SV _95-1肽脉冲的T2细胞，而且还有HLA-A2和SV阳性癌细胞）与天然SV _95-1肽和TIL2080细胞产生的癌细胞相比。这些发现表明SV _95-6SV95和SV _95-7肽是两个新的HLA-A2限制性CTL表位，可用于表达Survivin的癌症患者的免疫治疗。