Amniochorionic Membrane Cells in the Maternal Blood as a Biomarker for Preterm Birth

Globally, preterm birth (15 mill. per year) is the leading cause of under-5 child mortality (1 mill. per year) and morbidity. Important pathways include preterm labor contractions, Preterm Prelabor Rupture of the Fetal Membranes (PPROM), and iatrogenic delivery. At labor, the fetal amniochorionic membrane undergoes a cellular senescence and shed fetal amniochorionic membrane cells (ACM cells) to the maternal circulation. In collaboration with the private firm ARCEDI Biotech and The University of Texas Medical Branch at Galveston, Aarhus University has identified specific antibodies, which can be used to isolate ACM cells from maternal blood. Thus, the aim of this study is 1) to characterize ACM cells by histological and immunological techniques, and 2) in a cohort assess their performance as biomarkers of amniochorionic membrane dysfunction, including early detection of threatening preterm birth. In perspective, the findings are expected to improve the diagnostics and treatment of preterm birth.

Study Overview

• Status: Completed
• Conditions: Preterm Birth; Preterm Labor; Preterm Premature Rupture of Membrane

Detailed Description

Aim:

The aim of the study is 1) to characterize circulating fetal amniochorionic membrane cells (ACM cells) in pregnant women and 2) to investigate if they can function as biomarkers of amniochorionic membrane dysfunction, including risk of preterm birth.

Background:

Globally, preterm birth (15 mill. per year) is the leading cause of under-5 child mortality (1 mill. per year) and morbidity. Important pathways include preterm labor contractions (PLC), Preterm Prelabor Rupture of the Fetal Membranes (PPROM), and iatrogenic delivery due to preeclampsia and fetal growth restriction.

At labor, the fetal amniochorionic membrane undergoes a cellular senescence and shed fetal amniochorionic membrane cells (ACM cells) to the maternal circulation. Similar features are expected to be seen in cases with PPROM. In collaboration with ARCEDI Biotech Aps and the University of Texas Medical Branch at Galveston, Aarhus University has identified specific fetal membrane cell markers, i.e. specific proteins highly expressed by the ACM cells. Commercially available antibodies specific for these identified proteins can be used to isolate ACM cells from the maternal blood. The preliminary studies indicate that circulating ACM cells are present in the second half of pregnancy but not in the first half of pregnancy.

The investigators want to confirm by immunohistochemistry that specific antibodies can identify ACM cells in the fetal membranes, and that they can be a platform for isolating ACM cells from the maternal circulation.

Materials and Methods:

The investigators will isolate ACM cells from maternal blood by Magnetic Activating Cell Sorting (MACS) using different specific antibodies for ACM cells. The enriched ACM cells will be stained using fluorescent-labeled cytokeratin and vimentin antibodies, and sorted individually by Fluorescence Activated Cell Sorting (FACS). The true identification of the fetal derived ACM cells will be done by Short Tandem Repeat (SRT) analysis.

The antibodies that perform best will be selected based on pilot studies on pregnant women at term and in gestation week 12, 20, 28 and 34, as well as at labor and post partum. The protein expression and specificity of each antibody will be confirmed by immunohistochemistry and bright field microscopy on biopsies from the fetal membranes, placental tissue, and the placental bed in the uterus.

The established protocol will be used to evaluate the number of ACM cells in the maternal blood in normal and pathological pregnancies on cross sectional cohorts of term pregnant women with and without labor contractions and spontaneous rupture of membranes, women with PLC before 34 weeks gestation, women with PPROM before 34 weeks gestation, and a control group at gestational age 25+0 to 37.

Perspectives:

In the future, the results are expected to improve the diagnostics and treatment of threatening preterm birth, thus preventing mortality and morbidity in millions of children worldwide.

• Study Type: Observational
• Enrollment (Actual): 83

Contacts and Locations

Study Locations

• Denmark
  • Aarhus, Denmark, 8200
    • Aarhus University Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Pregnant women who complies to the above mentioned inclusion and exclusion criteria.

Description

Inclusion Criteria:

• Normal pregnancy at term (> 37 weeks) the day before a planned caesarean section.
• Normal pregnancy at term (> 37 weeks) with planned vaginal delivery.
• Women with preterm labor contractions < 34 weeks admitted at the hospital.
• Women with PPROM < 34 weeks admitted at the hospital.
• Normal pregnancy at gestational age 25+0 to 37.
• Normal pregnancy at gestational age 12 included at the nuchal translucency scan.
• Normal pregnancy at birth.

Exclusion Criteria:

• Maternal age < 18
• Women who does not understand the oral or written information
• Women who does not speak Danish
• Women who does not want to participate
• Women with complications in pregnancy

Study Plan

How is the study designed?

Number of groups / cohorts

8

Cohorts and Interventions

Group / Cohort
Term pregnant women without labor contractions or rupture of membranes; Term pregnant women > 37 weeks gestation with a normal pregnancy. One blood sample before a scheduled caesarean section.
Term pregnant women with labor contractions; Term pregnant women > 37 weeks gestation with a normal pregnancy. One blood sample when labor contractions, but before spontaneous rupture of membranes.
Term pregnant women with spontaneous rupture of membranes; Term pregnant women > 37 weeks gestation with a normal pregnancy. One blood sample after spontaneous rupture of membranes, but without labor contractions.
Preterm labor contractions (PLC); One blood sample when labor contractions before 34 weeks gestation without rupture of membranes.
Preterm Prelabor Rupture of the Fetal Membranes (PPROM); One blood sample when rupture of the fetal membranes before 34 weeks gestation without labor contractions.
Control group; Women with normal pregnancies. One blood sample in gestation week 25+0 to 37 matched as controls for PLC and PPROM cases.
Longitudinal cohort during pregnancy; Women with normal pregnancies, where blood samples will be collected at week 12, 20, 28, 34 and 36, as well as at labor.
Longitudinal cohort post partum; Women with normal pregnancies, where blood samples will be collected at labor, as well as 2 days, and 4, 8 and 12 weeks after birth.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
ACM cells in maternal blood	Number	At inclusion

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Gestational age at delivery	Weeks+days	At delivery
Birth weight of child	Kg	At delivery
APGAR score	<4, 4-7, or >7	At delivery
Sex of child	M/F	At delivery

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Maternal age	Years	At inclusion
Maternal BMI	kg/m	At inclusion

Collaborators and Investigators

• Sponsor: University of Aarhus
• Collaborators: Medical University of Graz; Aarhus University Hospital; The University of Texas Medical Branch, Galveston; Arcedi Biotech
• Investigators: Study Chair: Ramkumar Menon, PhD, University Of Texas Medical Branch At Galveston; Study Chair: Torben Steiniche, DMSc, Aarhus University Hospital; Principal Investigator: Palle Schelde, MSc, ARCEDI Biotech; Study Chair: Ripudaman Singh, PhD, ARCEDI Biotech; Study Chair: Berthold Huppertz, PhD, Medical University of Graz

Study record dates

Study Major Dates

• Study Start (Actual): August 15, 2022
• Primary Completion (Actual): June 28, 2024
• Study Completion (Actual): June 28, 2024

Study Registration Dates

• First Submitted: December 1, 2020
• First Submitted That Met QC Criteria: January 8, 2021
• First Posted (Actual): January 12, 2021

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: December 17, 2024
• Last Verified: December 1, 2024

More Information

Terms related to this study

• Keywords: Amniochorionic Membrane Cells; Fetal Membrane Cells
• Additional Relevant MeSH Terms: Urogenital Diseases; Wounds and Injuries; Female Urogenital Diseases and Pregnancy Complications; Obstetric Labor Complications; Pregnancy Complications; Premature Birth; Fetal Membranes, Premature Rupture; Rupture; Obstetric Labor, Premature
• Other Study ID Numbers: AU011020

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No