Innate lymphocyte-induced CXCR3B-mediated melanocyte apoptosis is a potential initiator of T-cell autoreactivity in vitiligo

Nat Commun. 2019 May 16;10(1):2178. doi: 10.1038/s41467-019-09963-8.

Abstract

T-cells play a crucial role in progression of autoimmunity, including vitiligo, yet the initial steps triggering their activation and tissue damage remain unknown. Here we demonstrate increased presence of type-1 innate lymphoid cells (NK and ILC1)-producing interferon gamma (IFNγ) in the blood and in non-lesional skin of vitiligo patients. Melanocytes of vitiligo patients have strong basal expression of chemokine-receptor-3 (CXCR3) isoform B which is directly regulated by IFNγ. CXCR3B activation by CXCL10 at the surface of cultured human melanocytes induces their apoptosis. The remaining melanocytes, activated by the IFNγ production, express co-stimulatory markers which trigger T-cell proliferation and subsequent anti-melanocytic immunity. Inhibiting the CXCR3B activation prevents this apoptosis and the further activation of T cells. Our results emphasize the key role of CXCR3B in apoptosis of melanocytes and identify CXCR3B as a potential target to prevent and to treat vitiligo by acting at the early stages of melanocyte destruction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Apoptosis / immunology
  • Autoimmunity*
  • Biopsy
  • Cells, Cultured
  • Chemokine CXCL10 / metabolism
  • Female
  • Humans
  • Immunity, Innate
  • Interferon-gamma / immunology
  • Interferon-gamma / metabolism
  • Killer Cells, Natural / immunology
  • Killer Cells, Natural / metabolism
  • Lymphocyte Activation
  • Male
  • Melanocytes / immunology*
  • Melanocytes / metabolism
  • Middle Aged
  • Primary Cell Culture
  • Protein Isoforms / immunology
  • Protein Isoforms / metabolism
  • Receptors, CXCR3 / immunology
  • Receptors, CXCR3 / metabolism*
  • Skin / cytology
  • Skin / pathology
  • T-Lymphocytes / immunology*
  • T-Lymphocytes / metabolism
  • Vitiligo / blood
  • Vitiligo / immunology*
  • Vitiligo / pathology

Substances

  • CXCL10 protein, human
  • CXCR3 protein, human
  • Chemokine CXCL10
  • Protein Isoforms
  • Receptors, CXCR3
  • Interferon-gamma