Strain differences in endometriosis models

Endometriosis is a common condition characterized by the presence of ectopic endometrial tissue outside the uterus. Key features of endometriosis include dysregulated cell proliferation, inflammation and fibrosis. Although several rodent models have been developed to study endometriosis, few accurately replicate the progressive fibrosis observed in the human condition. A new study compared three different inbred mouse strains—C57BL/6J, BALB/c and Swiss albino—to identify the most suitable for developing a fibrotic syngeneic model of endometriosis. Adapting an established protocol, the investigators intraperitoneally transplanted uterine fragments from donor mice into recipient mice, before performing behavioral assessments at days 16–18 post-induction and subsequently collecting tissues for various analyses. The results showed that mouse models from all strains displayed increased mechanical hyperalgesia and reduced exploratory behavior compared to controls, indicative of pain and anxiety. Macroscopic examination at necropsy revealed that 92.85%, 83.33% and 64.28% of C57BL/6J, BALB/c and Swiss mice developed endometriosis, respectively. Further analysis also showed strain-dependent dysregulation of inflammation and differences in the expression of fibrotic markers. Altogether, the findings suggest that the C57BL/6J strain is the most suitable for recapitulating the inflammatory and fibrotic processes of human endometriosis. Original reference: Anchan, M. et al. Sci. Rep. 15, 29024 (2025) This is a preview of subscription content, access via your institution Access options Author information Authors and Affiliations Corresponding author Rights and permissions About this article Cite this article Le Bras, A. Strain differences in endometriosis models. Lab Anim 54, 255 (2025). https://doi.org/10.1038/s41684-025-01627-z Published: Version of record: Issue date: DOI: https://doi.org/10.1038/s41684-025-01627-z