Macrophage-derived migrasomes promote fibrotic remodeling in endometriosis with TGF-β/Smad signaling activation

Background Progressive fibrosis of ectopic lesions is a major pathological feature of endometriosis and contributes to treatment resistance and disease recurrence. However, the mechanisms driving this fibrotic process remain incompletely understood.

A murine model of endometriosis was established by transplanting endometrial tissue fragments into the peritoneal cavity of C57BL/6 mice. Migrasome-enriched preparations were obtained from cultured RAW264.7 macrophages, characterized by morphological and molecular analyses, and administered intraperitoneally to endometriosis-bearing mice. Fibrotic changes were evaluated by histological analysis, while TGF-β/Smad signaling and EMT-related markers were assessed by Western blotting and immunofluorescence. Fibrosis-associated factors were further measured by enzyme-linked immunosorbent assay (ELISA).

Exogenously administered RAW264.7-derived migrasome preparations were detected at ectopic lesion sites and were associated with enhanced fibrotic changes. Masson’s trichrome staining revealed increased collagen deposition. Western blot analysis of ectopic lesion tissues revealed increased phosphorylation of Smad2 and Smad3 without significant changes in Smad2 and Smad3 levels, supporting the activation of the transforming growth factor-beta (TGF-β)/Smad pathway. Migrasome treatment was also associated with increased α-smooth muscle actin and vimentin expression together with reduced cytokeratin 18 (CK18) and E-cadherin expression, which is consistent with EMT-like phenotypic changes. In parallel, the levels of TGF-β1 and vascular endothelial growth factor (VEGF) were elevated, whereas the level of matrix metalloproteinase-9 (MMP9) was reduced. The fibrotic changes observed with the RAW264.7-derived preparations were also reproduced using primary BMDM-derived preparations, whereas comparable changes were not observed with the corresponding heat-inactivated preparations.

These findings provide evidence linking macrophage-derived migrasomes to fibrotic remodeling in endometriosis and suggest that migrasome-associated processes may contribute to lesion fibrosis. This work provides new insight into endometriosis-associated fibrosis and establishes a basis for further investigation of the underlying mechanisms and potential therapeutic relevance of migrasomes. Plain English summary Endometriosis occurs when tissue similar to the lining of the uterus grows outside the uterus, often causing pain and fertility problems. Over time, these lesions can develop fibrosis, involving excessive accumulation of collagen and other components of scar-like tissue, which may contribute to disease progression and recurrence. However, the mechanisms underlying fibrosis in endometriosis are not fully understood. In this study, we investigated whether migrasomes—small membrane-bound structures produced by migrating cells—may be involved in this process. Using a mouse model of endometriosis, we found that macrophage-derived migrasome preparations could reach ectopic lesion sites. Migrasome-treated lesions showed increased collagen deposition. We also observed activation of the TGF-β/Smad pathway, a signaling pathway closely associated with fibrosis, together with changes in epithelial and mesenchymal cell markers consistent with EMT-like phenotypic changes. These findings suggest that macrophage-derived migrasomes may be associated with fibrotic remodeling in endometriosis. Our study provides new evidence linking migrasomes to endometriosis-associated fibrosis, although the exact mechanisms remain to be determined. Further studies are needed to identify the molecules carried by migrasomes, determine which cells they affect within lesions, and explore their potential relevance as future therapeutic targets. Similar content being viewed by others Abbreviations - Abbreviation: - Full Name - α-SMA: - Alpha-smooth muscle actin - ANOVA: - Analysis of variance - CK18: - Cytokeratin 18 - CTGF: - Connective tissue growth factor - DAPI: - 4’,6-diamidino-2-phenylindole - DMEM: - Dulbecco’s Modified Eagle Medium - ECM: - Extracellular matrix - EOGT: - EGF domain-specific O-linked N-acetylglucosamine transferase - ELISA: - Enzyme-linked immunosorbent assay - EMS: - Endometriosis - EMT: - Epithelial–mesenchymal transition - EMP: - Epithelial–mesenchymal plasticity - EndoMT: - Endothelial-to-mesenchymal transition - FBS: - Fetal bovine serum - FMT: - Fibroblast-to-myofibroblast transdifferentiation - GAPDH: - Glyceraldehyde-3-phosphate dehydrogenase - GnRH-a: - Gonadotropin-releasing hormone agonist - H&E: - Hematoxylin and eosin - IVC: - Individually ventilated cage - KEGG: - Kyoto Encyclopedia of Genes and Genomes - MMT: - Macrophage-to-myofibroblast transition - MMP9: - Matrix metalloproteinase-9 - SDS‒PAGE: - Sodium dodecyl sulfate‒polyacrylamide gel electrophoresis - SEM: - Standard error of the mean - SPF: - Specific pathogen-free - TGF-β: - Transforming growth factor-beta - TSPAN4: - Tetraspanin 4 - VEGF: - Vascular endothelial growth factor

We are thankful to the anonymous reviewers for reviewing our manuscript and providing helpful comments and suggestions. Clinical trial number Not applicable. This study did not involve a clinical trial. Funding This work was supported by the Medical Scientific Research Foundation of Jiangsu Commission of Health (Grant No. K2024018), the Young Talent Development Plan of Changzhou Commission (Grant No. CZQM2020117), the Science and Technology Plan Project of Changzhou (Grant No. CJ20243001), the “14th Five-Year Plan” High-level Talents Training Project of Changzhou (Grant No. 2022CZBJ101) and the Postgraduate Research & Practice Innovation Program of Jiangsu Province (Grant No. KYCX24_3921). The funding bodies played no role in the design of the study; the collection, analysis, or interpretation of the data; or the writing of the manuscript. Author information Authors and Affiliations Corresponding authors Ethics declarations Ethics approval and consent to participate All animal experiments were performed in strict accordance with the National Institutes of Health Guide for the Care and Use of Laboratory Animals (8th edition, 2011) and were approved by the Animal Ethics Committee of Jiangsu University (Approval No. UJS-AEC-2025-14566). The maximum allowable size of an ectopic lesion permitted by the committee is 15 mm in diameter. In this study, all the ectopic lesions measured at the experimental endpoint were within this limit (mean diameter < 8 mm), and no lesions exceeded the permitted maximal tumor burden. This study did not involve human participants; therefore, consent to participate is not applicable. Consent for publication Not applicable. This manuscript does not contain any individual person’s data in any form (including individual details, images, or videos). Competing interests The authors declare no competing interests. Additional information Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Rights and permissions Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/. About this article Cite this article Lü, P., Fang, J., Zhang, S. et al. Macrophage-derived migrasomes promote fibrotic remodeling in endometriosis with TGF-β/Smad signaling activation. Cell Commun Signal (2026). https://doi.org/10.1186/s12964-026-03338-5 Received: Accepted: Published: DOI: https://doi.org/10.1186/s12964-026-03338-5