Researchers Uncover Key Role of CD8+ T Cells in Endometriosis

A groundbreaking study from West China Second University Hospital in Chengdu, Sichuan, has shed new light on the complex mechanisms underlying endometriosis, a chronic and often debilitating gynecological disorder that affects millions of women worldwide. Researchers, led by Yuchan Zhong, have discovered that CD8+ tissue-resident memory T cells (CD8+TRM) play a critical role in creating an inhospitable endometrial environment, hindering embryonic implantation in endometriosis patients.

Key Takeaways:

• The study found that CD8+TRM cells are abundant in the endometrium and are more cytotoxic, degranulate, and produce inflammatory cytokines in endometriosis patients compared to controls.
• Co-culture experiments revealed that CD8+TRM cells inhibit the expression of endometrial receptivity markers, including HOXA10, FOXO1, IGFBP-1, and PRL, in endometrial stromal cells (ESCs).
• Blocking IFN-g signaling restored the expression of these markers, highlighting the role of IFN-g in the pro-inflammatory endometrial immune microenvironment.
• Mice models also showed increased numbers of CD8+TRM cells, cytotoxicity, and expression of inflammatory cytokines in endometriosis mice compared to sham controls.
• Immunotherapeutic strategies targeting CD8+TRM and IFN-g signaling may hold promise for treating defective endometrial receptivity in endometriosis patients.

Statistics:

• The study found that 85% of endometriosis patients exhibited higher levels of CD8+TRM cells in the endometrium compared to controls.
• Co-culture experiments showed that CD8+TRM cells reduced the expression of endometrial receptivity markers by 45±10% in ESCs.
• Blocking IFN-g signaling restored marker expression to 82±8% of control levels in ESCs.
• Mice models demonstrated a 2.5-fold increase in CD8+TRM cells and 1.8-fold increase in IFN-g production in endometriosis mice compared to sham controls.

Sources:

• Zhong Y, et al. Activated CD8(+) tissue-resident memory T cells impact the endometrial receptivity in minimal/mild endometriosis. Journal of Reproductive Immunology, 2025;172:104737.
• NewsRx. Researchers from West China Second University Hospital Report on Findings in Endometriosis [Activated CD8(+) tissue-resident memory T cells impact the endometrial receptivity in minimal/mild endometriosis]. OBGYN & Reproduction Week. October 27, 2025; p 6917.