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Biphasic response of T cell activation to substrate stiffness.

ABSTRACT: T cell activation is sensitive to the mechanical properties of an activating substrate. However, there are also contrasting results on how substrate stiffness affects T cell activation, including differences between T cells of mouse and human origin. Towards reconciling these differences, this report examines the response of primary human T cells to polyacrylamide gels with stiffness between 5 and 110 kPa presenting activating antibodies to CD3 and CD28. T cell proliferation and IL-2 secretion exhibited a biphasic functional response to substrate stiffness, which can be shifted by changing density of activating antibodies and abrogated by inhibition of cellular contractility. T cell morphology was modulated by stiffness at early time points. RNA-seq indicates that T cells show differing monotonic trends in upregulated genes and pathways towards both ends of the stiffness spectrum. These studies provide a framework of T cell mechanosensing and suggest an effect of ligand density that may reconcile different, contrasting patterns of stiffness sensing seen in previous studies.

SUBMITTER: Yuan DJ

PROVIDER: S-EPMC8214245 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Biphasic response of T cell activation to substrate stiffness.

Yuan Dennis J DJ Shi Lingting L Kam Lance C LC

Biomaterials 20210412

T cell activation is sensitive to the mechanical properties of an activating substrate. However, there are also contrasting results on how substrate stiffness affects T cell activation, including differences between T cells of mouse and human origin. Towards reconciling these differences, this report examines the response of primary human T cells to polyacrylamide gels with stiffness between 5 and 110 kPa presenting activating antibodies to CD3 and CD28. T cell proliferation and IL-2 secretion e ...[more]

PMID: 33878536

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Biphasic response of T cell activation to substrate stiffness.

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Biphasic response of T cell activation to substrate stiffness.

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