“Killing me softly”: role of forces in stiffness-dependent tumour-cell killing by T cells (360G-Wellcome-215899_Z_19_Z)

My research proposal aims to study the influence of forces on immune cell activation and killing during tumour cell/target cell engagement. T cells have been reported to be stiffness dependently activated, but while this phenomenon is well known, the underlying mechanism remains unclear. With the following proposal I will link intracellular stresses in the actin network to actin assembly impairment and T-cell activation on various stiff targets. This will give unique insights into the mechanism of stiffness-dependent T-cell activation and killing and the role of actin in these processes. I propose to introduce stress reporters into T cells to visualise the distribution of stress within the actin network. I will then study the changes in force distribution upon T-cell activation on different stiff substrates using cell lines with mutations in the actin assembly machinery. I will continue the work by imaging primary cytotoxic cells and using state-of-the-art lightsheet imaging tools to visualise the 3D force distribution during T cell/tumour cell engagement. This is the first study able to uncover the role of intracellular forces in T-cell activation and killing, if force thresholds need to be met to lead to full activation, and what role actin assembly has in this process.