Prof. Mark Schvartzman
Department of Materials Engineering, Ilse Katz Institute for the Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
It is becoming progressively clear that the immune response of lymphocytes is regulated by physical cues, such as the spatial arrangement of signalling molecules, as well as mechanical stiffness and topography of their environment Yet, understanding the role of each cue in cell function is challenged by the fact that in vivo these cues are intermixed, and their effects on cells are often indistinguishable from each other. This challenge can be overcome by ex-vivo platforms for cell stimulation, which are designed to controllably mimic individual physical cues identical to those existing in vivo. Recent nanotechnological advances enable the structuring and positioning of these cues with a precision that reaches the molecular regime. Furthermore, these cues can be leveraged to control ex-vivo lymphocyte activation in immunotherapy.
In the first part of my talk, I'll discuss platforms studying physical cues in lymphocyte signaling. One initial work focused on ligand arrangement in Natural Killer (NK) cells, using stimulating platforms that precisely controlled how segregation between activating and inhibitory ligands affects NK cell signaling and cytotoxic function1. Varying ligand segregation from 0 nm to 40 nm revealed inhibition dependency on ligand spacing, supported by physical modelling of ligand-receptor binding kinetics. In the follow up work, we engineered platforms that controlled the nanoscale clustering of activating and costimulatory ligands in T cells, and demonstrated that such clustering is crucial for T cell activation at the low ligand densities. Lastly, we investigated environmental elasticity and nanoscale topography's role in T and NK cell activation using a tunable platform of vertical ultra-elastic nanowires with antigens2. Nanowires provide mechanical and nano-topographical cues, enhancing immune response, with easily adjustable dimensions3–5.
In the second part of my talk, I'll discuss how we used insights from basic studies on T cell mechano-stimulation to develop a novel mechano-topographical platform for Chimeric Antigen Receptor (CAR) T cell therapy. This platform features an elastic surface with 3D micro-/ nano-pillar arrays functionalized with antibodies against activating and costimulatory receptors for T cells. We systematically assessed the effect of the pillar geometry and elasticity on T cell functions, including activation, exhaustion, proliferation, and CAR transduction efficiency. Multiple discriminant analysis identified optimal parameters, focusing on enhancing memory CAR T cell differentiation. Integrating these surfaces into standard T cell production protocols led to CAR T cells with superior anti-tumor efficacy compared to conventional methods. Validation through assays confirmed enhanced potency in various models, with transcriptomic analysis revealing increased genetic signatures associated with central memory T cells. These findings represent a significant advancement in CAR T cell immunotherapy, highlighting the potential of surface microstructure and elasticity to enhance therapeutic outcomes.
To realize some of these platforms described above, we have developed an innovative lithographic process based on the dry self-assembly of nanospheres, achieving remarkable precision and density of the nanosphere packing packing. In addition to enabling scalable fabrication of T cell-stimulating nanostructures, this fabrication process has also proven versatile for creating advanced nanostructures for optical and self-cleaning applications6.
1. Toledo, E. Le Saux, G… Schvartzman M.. Science. Adv. 7, eabc1640 (2021).
2. Le Saux, G. … Schvartzman, M, Adv. Mater. 31, 1805954 (2019).
3. Bhingardive, V. … Schvartzman. M. Adv. Funct. Mater. 31, 2103063 (2021).
4. Bhingardive, V. … Schvartzman. M Nano Lett 21, 4241–4248 (2021).
5. Bhingardive, V. … Schvartzman. M. Small 17, 2007347 (2021).
6. Tzadka, S…Schvartzman, M. ACS Apl. Mat. Interfaces, 16, 17846 (2024)