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Multiplexed Fluorescent Immunohistochemical Staining of Four Endometrial Immune Cell Types in Recurrent Miscarriage
Published on: August 4, 2021
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Increased C4d and Bb immunoreactivity and decreased MBL immunoreactivity characterise first-time pathologic
M Tunc Canda1, Latife Doganay Caglayan2, Namik Demir1
1a Department of Obstetrics and Gynaecology , Kent Hospital , İzmir , Turkey.
Summary
This study found that the classical and alternative complement pathways are overactive, while the lectin pathway is underactive in first-time miscarriages. These complement system imbalances suggest a role in early pregnancy loss.
Area of Science:
- Immunology
- Reproductive Biology
- Pathology
Background:
- The complement system, a crucial part of innate immunity, plays a role in various pregnancy complications.
- Previous research on miscarriage and complement pathways has often focused on recurrent miscarriage or antiphospholipid syndrome (APS).
- The specific roles of the three main complement pathways (classical, alternative, and lectin) in first-time pathologic first-trimester miscarriage remain largely unexplored in human studies.
Purpose of the Study:
- To investigate the involvement of the complement system, including the classical, alternative, and lectin pathways, in first-time pathologic first-trimester miscarriage.
- To compare the activity of complement pathway components in tissue samples from women experiencing pathologic miscarriage versus those with normal pregnancies.
Main Methods:
- A case-control study was conducted involving 126 women.
- Tissue samples from the decidua and villous trophoblasts were analyzed.
- Immunoreactivity for complement components C4d (classical pathway), Bb (alternative pathway), and MBL (lectin pathway) was assessed using a semi-quantitative histological scoring system (H-score).
Main Results:
- Significantly higher H-scores for C4d and Bb were observed in the decidua and villous tissues of women with pathologic miscarriage compared to controls.
- A significantly reduced H-score for MBL was found in the tissues from pathologic miscarriage cases.
- These findings indicate increased activity of the classical and alternative complement pathways and decreased activity of the lectin pathway in first-time pathologic first-trimester miscarriage.
Conclusions:
- The classical and alternative complement pathways appear to be upregulated in first-time pathologic first-trimester miscarriage.
- The lectin complement pathway seems to be downregulated in this condition.
- These findings suggest that dysregulation of all three complement pathways may contribute to the development of first-time pathologic first-trimester miscarriage.
