Scavenger receptor for hemoglobin in preterm prelabor rupture of membranes pregnancies complicated by histological chorioamnionitis

Abstract

Objective: We sought to evaluate the distribution of scavenger receptor for hemoglobin positive (CD163⁺) cells in the placenta and fetal membranes from pregnancies complicated by preterm prelabor rupture of membranes with respect to the presence and absence of histological chorioamnionitis. Methods: Sixty-two women with singleton pregnancies with a gestational age between 24+0 and 36+6 weeks were included in a prospective cohort study. CD163 was evaluated by immunohistochemistry in the placenta and fetal membranes. The number of CD163⁺ cells and neutrophils was counted in the following locations: fetal membranes’ amnion, chorion, and decidua, as well as the placenta’s amnion, chorionic plate, subchorionic fibrin, stem villi, terminal villi, and decidua. Results: CD163⁺ cells were found in all compartments of the placenta and the fetal membranes regardless of the inflammatory status. A positive correlation between the number of CD163⁺ cells and neutrophils in the subchorionic fibrin and the chorionic plate was found. The number of CD163⁺ cells was higher in the placental subchorionic fibrin and chorionic plate when histological chorioamnionitis was present. Conclusion: The presence of histological chorioamnionitis affected the number of CD163⁺ cells in the placental chorionic plate and in the subchorionic fibrin but not in the fetal membranes.

Keywords::

• Inflammation
• immunohistochemistry
• innate immunity
• recognition receptors
• preterm labor

Acknowledgements

This work was supported by grants from the Ministry of Education, Youth and Sports (ME 10025) and by the Research project (MZO 00179906). Additional support came from the Swedish Medical Society (SLS 2008–21198), Swedish government grants to researchers in the public health service (ALFGBG-2863, ALFGBG-11522) and The Göteborg Medical Society.

Declaration of Interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.