3D artificial lymph nodes to study the cross-correlation of biochemical and biomechanical signals during T cells activation

• Applicant: Dr. Oskar Staufer
• Subject Area: Biophysics ; Immunology
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 545610076

Phenotypic transition of T cells from a naïve resting state into a differentiated phenotype is a process fundamental to immunity that involves highly coordinated interactions between several cellular and molecular agents. Secondary lymphoid organs, such as lymph nodes (LNs), are key sites for T cell activation as they provide a specialized three-dimensional microenvironment that promotes antigen presentation by professional antigen-presenting cells (APCs). To regulate T cell activation, several stimulatory and regulatory proteins are presented on the lipid membranes of APCs in addition to the antigen itself. Recent studies have found that not only the type of proteins presented on APCs within LNs but also the mechanical properties of the APCs, are major regulators of T cell proliferation and differentiation into effector, memory and regulatory populations. Insights into the cross-correlation between biochemical and biomechanical cues underlaying T cell activation, are not only of fundamental importance for holistic understanding of cellular immunity but also for the development of advanced cell-based immunotherapies and next-generation vaccine technologies. In order provide a systematic analysis of the cross-correlation between biochemical and biomechanical APC stimuli, in this project, synthetic LNs (SYNODEs) assembled from oil droplet-based synthetic APCs will be developed and employed. For this, individual artificial APCs will be designed to form a millimeter-scale tissue-like material. Within SYNODEs, the mechanical properties and membrane protein presentation of the APC can be controlled and tuned independently, for presentation to naïve primary human T cells. T cell activation, proliferation and differentiation dynamics into various T cell effector, regulatory and memory subtypes will be studied using various microscopy and biochemical techniques. Moreover, T cell migration dynamics within the artificial tissue structure as well as formation of immune synapses and cytoskeletal remodeling will be studied by time-resolved live cell light sheet microscopy, to infer signal integration during T cell activation. Finally, the cytotoxic potency of CD8 T cells, expanded within SYNODEs under varying biochemical and biophysical environments, will be quantified in a CD3/Her2 bispecific T cell-engager model to correlate distinct environmental cues with effector T cell function for immunotherapy. Thus, the proposed project will develop an artificial lymph node technology to understand fundamental mechanism underlaying specific and directed T cell activation, which will aid in improving immunotherapeutic technologies and understanding on immune regulation mechanisms.

• DFG Programme: Research Grants