Cell surface morphology mimicking nano-bio platform for immune cell stimulation

Studying the complex realm of cellular communication and interactions by fluorescence microscopy requires sample fixation on a transparent substrate. To activate T cells, which are pivotal in controlling the immune system, it is important to present the activating antigen in a spatial arrangement similar to the nature of the antigen-presenting cell, including the presence of ligands on microvilli. Similar arrangement is predicted for some other immune cells. In this work, immune cell-stimulating platform based on nanoparticle-ligand conjugates have been developed using a scalable, affordable, and broadly applicable technology, which can be readily deployed without the need for state-of-the-art nanofabrication instruments. The validation of surface biofunctionalization was performed by combination of fluorescence and atomic force microscopy techniques. We demonstrate that the targeted system serves as a biomimetic scaffold on which immune cells make primary contact with the microvilli-mimicking substrate and exhibit stimulus-specific activation. [Display omitted] •Nanoparticle-ligand platform to mimic antigen-presenting cell microvilli•Specific T cell activation by naturally presented antibodies•Suppressed non-specific activation in fluorescence microscopy imaging•Broad benchtop applicability without advanced nanofabrication equipment Immunology; Biotechnology; Cell biology