Immunological changes associated with adenomyosis: a systematic review.

Area of Science:

• Gynecology
• Immunology
• Reproductive Medicine

Background:

• Adenomyosis is a benign gynecological disorder causing subfertility, pelvic pain, and abnormal uterine bleeding.
• It is characterized by endometrial tissue within the myometrium, a condition whose pathogenesis is not fully understood.
• Immune system activation and hormonal aberrations, including epithelial to mesenchymal transition (EMT), are implicated in adenomyosis development.

Purpose of the Study:

• To systematically review the scientific literature on the role of the immune system in the development of adenomyosis.
• To investigate immune system involvement in both the inner and outer myometrium in human subjects.

Main Methods:

• A systematic review of human studies published between 1970 and February 2019.
• Searches were conducted in MEDLINE, EMBASE, and Cochrane Library databases using specific keywords and MeSH terms related to adenomyosis and the immune system.
• Studies without a control group or those not comparing adenomyosis patients to disease-free individuals were excluded.

Main Results:

• 42 articles were included, revealing changes in innate and adaptive immune cells in women with adenomyosis.
• Increased lymphocyte and macrophage populations were observed in the eutopic endometrium of adenomyosis patients compared to controls.
• Elevated levels of both pro-inflammatory (e.g., IL-6, TNF-α) and anti-inflammatory (e.g., IL-10) cytokines were found in affected tissues. The study also noted links between immune changes, hormonal aberrations, and EMT.

Conclusions:

• Immunological changes, encompassing both inflammatory and anti-inflammatory signals, are clearly associated with adenomyosis.
• These immune alterations, potentially via EMT and in conjunction with endocrine imbalances, likely promote endometrial cell migration into the myometrium.
• Further understanding of the immune system's role in adenomyosis pathogenesis is crucial for developing new research avenues and potential therapeutic strategies.