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A study of the communication between the immune system and the placenta

​We are recruiting patients from Imperial College Healthcare NHS Trust to take part in this research.

Please read below for more information on:

- why we are doing this research

- useful documents

- updates on recruitment and study results

- our public engagement activities

During pregnancy, the placenta supports growth and development of a healthy baby, also providing protection from infection and inflammation. Passive immunity is imparted by active transfer of maternal IgG across the placenta, with higher levels observed in cord blood compared to maternal blood. Furthermore, specific diseases may be targeted via maternal vaccination, protecting infants too young for postnatal immunisation. IgGs must cross the syncytiotrophoblast, stroma, and fetal capillary endothelium, however the full pathway for transplacental movement has not been precisely described. In this regard, our first research question is ‘How does protective antibody transfer from mother to fetus across the placenta, and how is this altered following maternal vaccination?’. Communication between the maternal immune system and the fetus is inherent to the placentas protective role. This may be mediated by extracellular vesicles (EVs), small membrane-bound structures produced by many cell types with complex cargo including protein, RNA, miRNA,

DNA, lipids and glycans. Placental EVs are released into the maternal circulation throughout pregnancy, however the proportion of non-placental EVs increases later in pregnancy. Placental EVs have been implicated in pre-eclampsia pathology as pro-inflammatory agents and may cause a detrimental positive feedback loop. So, our second research question is ‘How do messages from the immune system affect the function of the placenta?’.

White File Folders


COMET Group 1 Participant Information Sheet

Version 1.7 (16.07.2019)

Information sheet for potential research participants having an elective caesarean section.

COMET Group 2 Participant Information Sheet

Version 1.7 (16.07.2019)

Information sheet for potential research participants having a surgical termination of pregnancy.

GDPR Statement


GDPR Transparency Statement

GDPR Statement


GDPR Transparency Statement

Clocks on Shelf


100th Participant Recruited

Tuesday 24th November 2020

Recruitment Paused due to the COVID-19 Pandemic

Wednesday 18th March - Wednesday 19th August 2020

50th Participant Recruited

Tuesday 28th January 2020

1st Participant Recruited

Tuesday 3rd September 2019

Ethics Approval


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