A Hydrogel-Integrated Culture Device to Interrogate T Cell Activation with Physicochemical Cues.

Matthew H W Chin,Eileen Gentleman,Richard M Day,Michael D A Norman,Marc-Olivier Coppens

doi:10.1021/acsami.0c16478

Matthew H W Chin, Eileen Gentleman + Show 3 more

Open Access

https://doi.org/10.1021/acsami.0c16478

Copy DOI

Abstract

The recent rise of adoptive T cell therapy (ATCT) as a promising cancer immunotherapy has triggered increased interest in therapeutic T cell bioprocessing. T cell activation is a critical processing step and is known to be modulated by physical parameters, such as substrate stiffness. Nevertheless, relatively little is known about how biophysical factors regulate immune cells, such as T cells. Understanding how T cell activation is modulated by physical and biochemical cues may offer novel methods to control cell behavior for therapeutic cell processing. Inspired by T cell mechanosensitivity, we developed a multiwell, reusable, customizable, two-dimensional (2D) polyacrylamide (PA) hydrogel-integrated culture device to study the physicochemical stimulation of Jurkat T cells. Substrate stiffness and ligand density were tuned by concentrations of the hydrogel cross-linker and antibody in the coating solution, respectively. We cultured Jurkat T cells on 2D hydrogels of different stiffnesses that presented surface-immobilized stimulatory antibodies against CD3 and CD28 and demonstrated that Jurkat T cells stimulated by stiff hydrogels (50.6 ± 15.1 kPa) exhibited significantly higher interleukin-2 (IL-2) secretion, but lower proliferation, than those stimulated by softer hydrogels (7.1 ± 0.4 kPa). In addition, we found that increasing anti-CD3 concentration from 10 to 30 μg/mL led to a significant increase in IL-2 secretion from cells stimulated on 7.1 ± 0.4 and 9.3 ± 2.4 kPa gels. Simultaneous tuning of substrate stiffness and stimulatory ligand density showed that the two parameters synergize (two-way ANOVA interaction effect: p < 0.001) to enhance IL-2 secretion. Our results demonstrate the importance of physical parameters in immune cell stimulation and highlight the potential of designing future immunostimulatory biomaterials that are mechanically tailored to balance stimulatory strength and downstream proliferative capacity of therapeutic T cells.

Highlights

IntroductionThe ability to sense mechanical cues in the environment − mechanosensitivity − has been observed in many types of cells
The ability to sense mechanical cues in the environment − mechanosensitivity − has been observed in many types of cells.This property underlies the fundamental functioning of numerous cellular processes, including cell spreading,[1] proliferation,[2] and differentiation.[3]
To systematically study the effect of substrate stiffness on T cell activation, we focused on PA hydrogels due to their wellknown biocompatibility and mechanical tunability in the kPa range.[27]

Summary

Introduction

The ability to sense mechanical cues in the environment − mechanosensitivity − has been observed in many types of cells. This property underlies the fundamental functioning of numerous cellular processes, including cell spreading,[1] proliferation,[2] and differentiation.[3] mechanosensitivity is known to play a critical role in tumorigenesis[4] and other pathological conditions. Recent studies have begun to unravel how mechanosensitivity enables tuning of essential immunological processes, such as T cell activation[6,7] and cytotoxic T lymphocyte (CTL)-mediated target cell killing.[10]

Methods

Discussion

Conclusion