A systematic review of toll-like receptors in endometriosis

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This systematic review analyzed studies on toll-like receptors in endometriosis and found increased expression of TLR2, TLR4, and TLR9 in women with the condition.

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This systematic review analyzed published studies on toll-like receptors (TLRs) in endometriosis, searching PubMed, SciELO, and Lilacs using keywords “endometriosis” and “toll-like” and assessing study quality with PRISMA and the Newcastle–Ottawa Scale. Across the included studies, women with endometriosis showed increased expression of TLRs 2, 4, and 9, with TLR4 being the most frequently reported receptor. The authors note that although elevated TLR levels are reported, the relationship between TLR expression and endometriosis remains unclear and requires further investigation into innate immune responses. This paper is centrally about endometriosis — it systematically reviews evidence linking TLRs (especially TLR2, TLR4, and TLR9) to the disease.

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Abstract

Introduction The pathogen-associated molecular patterns and the danger-associated molecular patterns are possibly responsible for the activation of the inflammatory process in endometriosis through the activation of toll-like receptors (TLRs).

Objective

The aim of this systematic review was to critically analyze the findings of published articles on TLRs in endometriosis.

Methods

The keywords used were “endometriosis” and “toll-like” and the search was performed in Pubmed, Scielo and Lilacs databases. This study followed the PRISMA guidelines and the risk of bias of articles was conducted by Newcastle–Ottawa scale (NOS).

Results

Overall, the studies analyzed in this review point toward an increased expression of TLRs two, four and nine in women with endometriosis. Among all TLRs, TLR4 was the most cited receptor.

Conclusion

Despite the evidence demonstrating elevated TLR levels in endometriosis, the relationship with the disease is still unclear and needs to be clarified in further studies about innate immune response. Similar content being viewed by others

References

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J Reprod Immunol. https://doi.org/10.1016/j.jri.2018.02.003 Funding This research did not receive any specific grant from any funding agency in the public, commercial, or not-for-profit sector. Author information Authors and Affiliations Contributions BCA and SP contributed to conception and design of the systematic review. BCA conducted the literature search, title/abstract review, abstracted. BCA and SP conducted the quality-assessed the included studies. FM prepared the Fig. 3, reviewed, and edited the manuscript. BCA and SP contributed to writing and revising the final manuscript. All authors read and approved the final manuscript. Corresponding author Ethics declarations Conflict of interest The authors declare that they have no conflict of interest. Ethical approval This is an observational study. The Research Ethics Committee at Hospital Israelita Albert Einstein–CEP/Einstein, has confirmed that no ethical approval is required. Additional information Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Supplementary Information Below is the link to the electronic supplementary material. Rights and permissions About this article Cite this article de Azevedo, B.C., Mansur, F. & Podgaec, S. A systematic review of toll-like receptors in endometriosis. Arch Gynecol Obstet 304, 309–316 (2021). https://doi.org/10.1007/s00404-021-06075-x Received: Accepted: Published: Version of record: Issue date: DOI: https://doi.org/10.1007/s00404-021-06075-x

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Condition tags

mesh:D004715endometriosis

MeSH descriptors

Endometriosis Toll-Like Receptors Endometriosis Female Humans Immunity, Innate Toll-Like Receptors

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