Cited by 58Genetic and Clinical Aspects of Sex Determination and Chromosomal AbnormalitiesImmune Response and InflammationGenomics and Chromatin Dynamics

TLR8 escapes X chromosome inactivation in human monocytes and CD4+ T cells

Open access
Youness, Ali, Cenac, Claire, Faz-López, Berenice, Grunenwald, Solange, Barrat, Franck J., Chaumeil, Julie, Mejía, José Enrique, Guéry, Jean-Charles·2023·Biology of Sex Differences

Published version of a preprint

Abstract

Background: Human endosomal Toll-like receptors TLR7 and TLR8 recognize self and non-self RNA ligands, and are important mediators of innate immunity and autoimmune pathogenesis. TLR7 and TLR8 are, respectively, encoded by adjacent X-linked genes. We previously established that TLR7 evades X chromosome inactivation (XCI) in female immune cells. Whether TLR8 also evades XCI, however, has not yet been explored. Method: In the current study, we used RNA fluorescence in situ hybridization (RNA FISH) to directly visualize, on a single-cell basis, primary transcripts of TLR7 and TLR8 relative to X chromosome territories in CD14 + monocytes and CD4 + T lymphocytes from women, Klinefelter syndrome (KS) men, and euploid men. To assign X chromosome territories in cells lacking robust expression of a XIST compartment, we designed probes specific for X-linked genes that do not escape XCI and therefore robustly label the active X chromosome. We also assessed whether XCI escape of TLR8 was associated with sexual dimorphism in TLR8 protein expression by western blot and flow cytometry. Results: Using RNA FISH, we show that TLR8 , like TLR7 , evades XCI in immune cells, and that cells harboring simultaneously TLR7 and TLR8 transcript foci are more frequent in women and KS men than in euploid men, resulting in a sevenfold difference in frequency. This transcriptional bias was again observable when comparing the single X of XY males with the active X of cells from females or KS males. Interestingly, TLR8 protein expression was significantly higher in female mononuclear blood cells, including all monocyte subsets, than in male cells. Conclusions: TLR8 , mirroring TLR7 , escapes XCI in human monocytes and CD4 + T cells. Co-dependent transcription from the active X chromosome and escape from XCI could both contribute to higher TLR8 protein abundance in female cells, which may have implications for the response to viruses and bacteria, and the risk of developing inflammatory and autoimmune diseases.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1186/s13293-023-00544-5

Cites

80 of 80 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • The contrasting roles of AmtRNA in males and females may be linked to the presence of TLR-7 and -8 genes on the X chromosome and their potential to escape X chromosome inactivation, thus leaving females with more gene copies of these TLRs.

    “How exactly AmtRNA may play contrasting roles in males and females is unclear, but this may be linked to the presence of TLR-7 and -8 genes on the X chromosome and their potential to escape X chromosome inactivation, thus leaving females with more gene copies of these TLRs [31,32].”

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

1 of the 81 references couldn’t be matched to a known paper.

Research works printed but not linked: 1

  1. [81]Bender M Christiansen J Quick M The terrible toll of 76 autoimmune diseases Sci Am 2021 325 3 31 33 39020675

Cited by

Sorted by citations

Authors
Youness, A., Cenac, C., Faz-López, B., Grunenwald, S., Barrat, F. J., Chaumeil, J., Mejía, J. E., & Guéry, J.-C.
Affiliations
  • Centre National de la Recherche Scientifique (FR)
  • Centre Hospitalier Universitaire de Toulouse (FR)
  • Hospital for Special Surgery (US)
Corresponding author
  • Mejía, José Enrique
  • Guéry, Jean-Charles
Venue
Biology of Sex Differences
Published
2023-09-18
Volume
14
Issue
1
Pages
60-60
ISSN
2042-6410 (ISSN-L)
OpenAlex
W4386839549
Cited by
58
References
81
Citations by year
2026: 21 · 2025: 22 · 2024: 15
FWCI
9.63
Type
journal article
Language
en
Open access
Locations
  • Biology of Sex Differences (publishedVersion, cc-by)
  • Research Square (acceptedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • HAL (submittedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
Funders
  • Agence Nationale de la Recherche (ANR-20-CE15-0014, ANR-20-COV8-0004-01)
  • Sidaction
  • Fonds de dotation CSL Behring pour la recherche
  • Foundation for Research in Rheumatology
  • Région Occitanie/Pyrénées-Méditerranée
  • Scleroderma Foundation
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Genetics › Genetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities
  • Life Sciences › Immunology and Microbiology › Immunology › Immune Response and Inflammation
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Genomics and Chromatin Dynamics
Keywords
TLR8, X chromosome inactivation, TLR7, monocytes, CD4+ T cells, Klinefelter syndrome, X-linked genes, sex differences, RNA fluorescence in situ hybridization, XIST, innate immunity, autoimmune disease susceptibility
MeSH terms
Female, Humans, Male, Monocytes, T-Lymphocytes, CD4-Positive T-Lymphocytes, In Situ Hybridization, Fluorescence, X Chromosome Inactivation, Toll-Like Receptor 7, Toll-Like Receptor 8

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review