Short telomere syndromes cause a primary T cell immunodeficiency

J Clin Invest. 2018 Dec 3;128(12):5222-5234. doi: 10.1172/JCI120216. Epub 2018 Oct 22.

Abstract

The mechanisms that drive T cell aging are not understood. We report that children and adult telomerase mutation carriers with short telomere length (TL) develop a T cell immunodeficiency that can manifest in the absence of bone marrow failure and causes life-threatening opportunistic infections. Mutation carriers shared T cell-aging phenotypes seen in adults 5 decades older, including depleted naive T cells, increased apoptosis, and restricted T cell repertoire. T cell receptor excision circles (TRECs) were also undetectable or low, suggesting that newborn screening may identify individuals with germline telomere maintenance defects. Telomerase-null mice with short TL showed defects throughout T cell development, including increased apoptosis of stimulated thymocytes, their intrathymic precursors, in addition to depleted hematopoietic reserves. When we examined the transcriptional programs of T cells from telomerase mutation carriers, we found they diverged from older adults with normal TL. Short telomere T cells upregulated DNA damage and intrinsic apoptosis pathways, while older adult T cells upregulated extrinsic apoptosis pathways and programmed cell death 1 (PD-1) expression. T cells from mice with short TL also showed an active DNA-damage response, in contrast with old WT mice, despite their shared propensity to apoptosis. Our data suggest there are TL-dependent and TL-independent mechanisms that differentially contribute to distinct molecular programs of T cell apoptosis with aging.

Keywords: Aging; Genetics; Telomeres.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aging / genetics
  • Aging / immunology
  • Aging / pathology
  • Animals
  • Apoptosis / genetics
  • Apoptosis / immunology*
  • DNA Damage / immunology
  • Female
  • Growth Disorders* / complications
  • Growth Disorders* / genetics
  • Growth Disorders* / immunology
  • Growth Disorders* / pathology
  • Humans
  • Hypercalcemia* / complications
  • Hypercalcemia* / genetics
  • Hypercalcemia* / immunology
  • Hypercalcemia* / pathology
  • Immunologic Deficiency Syndromes* / etiology
  • Immunologic Deficiency Syndromes* / genetics
  • Male
  • Metabolic Diseases* / complications
  • Metabolic Diseases* / genetics
  • Metabolic Diseases* / immunology
  • Metabolic Diseases* / pathology
  • Mice
  • Mice, Knockout
  • Mutation*
  • Nephrocalcinosis* / complications
  • Nephrocalcinosis* / genetics
  • Nephrocalcinosis* / immunology
  • Nephrocalcinosis* / pathology
  • Primary Immunodeficiency Diseases
  • T-Lymphocytes / immunology
  • T-Lymphocytes / pathology
  • Telomerase* / genetics
  • Telomerase* / immunology
  • Telomere Homeostasis / immunology*

Substances

  • Telomerase

Supplementary concepts

  • SHORT syndrome
  • T cell immunodeficiency primary