Genetic Engineering Tumour Infiltrating Lymphocytes (TILs) to achieve enhanced tumour killing

最近的重大突破使得范式转变细胞免疫疗法的发展成为可能，这些疗法改变了血液癌症的治疗。然而，仍然迫切需要开发细胞免疫疗法来治疗实体瘤。许多实体瘤含有肿瘤浸润淋巴细胞（TIL），这些细胞可以分离、体外扩增并重新输注回患者体内。这种方法在临床试验中显示出很大的前景，尽管一些患者没有反应，因此TIL治疗需要进一步改进和优化。TIL识别来源于在主要组织相容性复合物I类分子（MHCI）的背景下呈递在癌细胞表面的癌抗原的小肽片段。肽-MHCI复合物的识别由两种T细胞表面表达的受体介导：T细胞受体（TCR）和CD 8共受体。TCR介导抗原特异性，而CD 8起增强T细胞敏感性的作用，并具有微调T细胞应答的强大能力。抗癌特异性TCR通常是低亲和力的，这导致癌细胞的T细胞识别差。克服这一点的一种策略是将高亲和力CD 8分子引入患者来源的TIL中。由于CD 8的多态性，这种方法将在全球范围内适用于来自任何患者的TIL。在这里，我们将使用高亲和力的CD 8分子，这些分子已经过生物学验证，并显示出对MHCI具有增强的亲和力。选择这些高亲和力CD 8分子是因为它们对MHCI的亲和力位于预定义的亲和力窗口内，所述预定义的亲和力窗口被设计成能够优化pMHCI/CD 8相互作用以用于治疗目的而不触发非特异性T细胞活化。在这个项目中，学生将确定高亲和力CD 8分子增强pMHCI/CD 8相互作用强度的分子机制，用高亲和力CD 8分子设计T细胞，并评估这种方法增强T细胞杀伤肿瘤细胞的能力。该项目将推进我们的目标，即能够利用合成生物学方法来设计TIL，以改善实体瘤的治疗。

Major breakthroughs have recently enabled the development of paradigm-shifting cellular immunotherapies which have transformed the treatment of blood cancers. However, there remains an urgent need to develop cellular immunotherapies to treat solid tumours. Many solid tumours contain Tumour Infiltrating Lymphocytes (TILs) which can be isolated, expanded in vitro and re-infused back into the patient. This approach has shown great promise in clinical trials, although some patients do not respond and as such TIL therapy requires further refinement and optimisation. TILs recognize small peptide fragments derived from cancer antigens presented at the cancer cell surface in the context of Major Histocompatibility Complex Class I Molecules (MHCI). The recognition of peptide-MHCI complexes is mediated by two T-cell surface expressed receptors: the T-cell receptor (TCR) and the CD8 co receptor. The TCR mediates antigen specificity, whereas CD8 acts to enhance T-cell sensitivity and has a potent ability to fine-tune the T-cell response. Anti-cancer specific TCRs are often low affinity which results in poor T-cell recognition of cancer cells. One strategy to overcome this would be to introduce high affinity CD8 molecules into patient derived TILs. This approach would be globally applicable to TILs from any patient due to the polymorphic nature of CD8. Here we will use high affinity CD8 molecules which have been biophysically validated and shown to have an enhanced affinity for MHCI. These high affinity CD8 molecules have been selected because their affinity for MHCI sits within a pre-defined affinity window designed to enable the optimization of the pMHCI/CD8 interaction for therapeutic purposes without triggering nonspecific T-cell activation. In this project the student will determine the molecular mechanism by which high affinity CD8 molecules enhance the strength of the pMHCI/CD8 interaction, engineer T-cells with high affinity CD8 molecules and assess the ability of this approach to enhance T-cell killing of tumour cells. The project will advance our aim of being able to utilise a synthetic biology approach to engineer TILs for the improved treatment of solid tumours.