Skin-Resident Effector Memory CD8+CD28- T Cells Exhibit a Profibrotic Phenotype in Patients with Systemic Sclerosis.

Abstract

Loss of CD28 expression by CD8+ T cells occurs with age and during chronic inflammatory conditions. CD8+CD28- T cells are a heterogeneous cell subpopulation whose function ranges from immunosuppressive to effector. Here we analyzed the role of CD8+CD28- T cells in the pathogenesis of systemic sclerosis (SSc), a connective tissue disorder characterized by autoimmunity, vasculopathy, and extensive cutaneous and visceral fibrosis. We show that the frequency of CD8+CD28- T cells is increased in the blood and affected skin of SSc patients, independent of patient age, and correlates with the extent of skin fibrosis. We found that most skin-tropic CD8+CD28- T cells are resident in the skin lesions of patients in the early stage of the disease, exhibit an effector memory phenotype, and present a strong cytolytic activity ex vivo. Skin-resident and circulating SSc CD8+CD28- T cells produce high levels of the profibrotic cytokine IL-13, which induces collagen production by normal and SSc dermal fibroblasts. Thus, our findings indicate that CD8+CD28- T cells represent a pathogenic T-cell subset in SSc and likely play a critical role in the early stage of SSc skin disease.

DOI: 10.1016/j.jid.2016.11.037

Cite this paper

@article{Li2017SkinResidentEM, title={Skin-Resident Effector Memory CD8+CD28- T Cells Exhibit a Profibrotic Phenotype in Patients with Systemic Sclerosis.}, author={Gang Li and Adriana T. Larregina and Robyn T. Domsic and Donna B Stolz and Thomas A Jr Medsger and Robert A. Lafyatis and Patrizia Fuschiotti}, journal={The Journal of investigative dermatology}, year={2017}, volume={137 5}, pages={1042-1050} }