Unravelling CD4+ T cell diversity and tissue adaptation of Tregs in abdominal aortic aneurysms through single-cell sequencing

Immunology. 2024 Aug;172(4):600-613. doi: 10.1111/imm.13796. Epub 2024 Apr 18.

Abstract

Immune cell infiltration is a significant pathological process in abdominal aortic aneurysms (AAA). T cells, particularly CD4+ T cells, are essential immune cells responsible for substantial infiltration of the aorta. Regulatory T cells (Tregs) in AAA have been identified as tissue-specific; however, the time, location, and mechanism of acquiring the tissue-specific phenotype are still unknown. Using single-cell RNA sequencing (scRNA-seq) on CD4+ T cells from the AAA aorta and spleen, we discovered heterogeneity among CD4+ T cells and identified activated, proliferating and developed aorta Tregs. These Tregs originate in the peripheral tissues and acquire the tissue-specific phenotype in the aorta. The identification of precursors for Tregs in AAA provides new insight into the pathogenesis of AAA.

Keywords: CD4+ T cells; T‐lymphocytes, regulatory; aortic aneurysm, abdominal.

MeSH terms

  • Animals
  • Aortic Aneurysm, Abdominal* / immunology
  • Aortic Aneurysm, Abdominal* / pathology
  • CD4-Positive T-Lymphocytes / immunology
  • Humans
  • Lymphocyte Activation
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Sequence Analysis, RNA
  • Single-Cell Analysis*
  • Spleen / immunology
  • T-Lymphocytes, Regulatory* / immunology