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Updated: Jul 2, 2026
10:13
Purification of HLA-G+ Extravillous Trophoblasts from Human Term Placental Tissues for Phenotyping and Functional Analysis
Published on: March 13, 2026
Bcl-2 and Bax expressions in pre-term, term and post-term placentas
Silvia Daher1, Alberto J Guimarães, Rosiane Mattar
1Department of Obstetrics, Paulista Medical School, São Paulo Federal University, São Paulo, Brazil. silviadaher@hotmail.com
Summary
Imbalances in placental apoptotic proteins, Bax and Bcl-2, are linked to pre-term and post-term birth. The Bax/Bcl-2 ratio was higher in abnormal term placentas, suggesting a role in birth timing disorders.
Area of Science:
- Obstetrics and Gynecology
- Cell Biology
- Developmental Biology
Background:
- Apoptosis, or programmed cell death, plays a critical role in placental development and function.
- Dysregulation of apoptotic pathways has been implicated in various pregnancy complications, including preterm and post-term birth.
Purpose of the Study:
- To investigate the expression and distribution of pro-apoptotic (Bax) and anti-apoptotic (Bcl-2) proteins in placentas from term, preterm, and post-term deliveries.
- To determine if an imbalance in these proteins is associated with abnormal birth timing.
Main Methods:
- Immunohistochemistry was used to assess the expression of Bax and Bcl-2 proteins in placental tissue samples.
- Samples were obtained from women with term (n=25), preterm (n=7), and post-term (n=10) deliveries.
Main Results:
- While the staining pattern for Bax and Bcl-2 was consistent across all groups, the intensity varied.
- The Bax/Bcl-2 ratio was significantly higher in preterm and post-term placentas compared to term placentas.
- This elevated ratio was attributed to increased Bax reactivity and, in preterm placentas, decreased Bcl-2 expression.
Conclusions:
- The findings suggest that altered expression of apoptosis-associated proteins in the placenta may contribute to the physiopathology of preterm and post-term birth.
- Different mechanisms of apoptotic protein imbalance might be involved in the development of preterm versus post-term birth.
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