Work

Serum CD63–PLAP placenta Extracellular Vesicles for Early Detection of Early-Onset Preeclampsia -Validation by ExoCounter in a Tanzanian Cohort

Year: 2026

Type: preprint

Abstract: Early-onset preeclampsia (EOPE) is a severe pregnancy complication associated with high maternal and perinatal morbidity. Effective first-trimester screening followed by aspirin prophylaxis reduces EOPE incidence, but current risk stratification models (e.g., FMF) require advanced ultrasound and laboratory resources, limiting feasibility in low- and middle-income countries. Extracellular vesicles (EVs) from the placenta represent a promising, minimally invasive biomarker. We conducted a retrospective case–control analysis of prospectively collected serum and plasma samples from 75 Tanzanian women, including normotensive pregnancies (NP, n_serum = 19, n_plasma = 5), EOPE (n_serum = 19, n_plasma = 5), and late-onset preeclampsia (LOPE, n_serum = 20, n_plasma = 5). Using ExoCounter, we quantified psEVs with CD63–PLAP, CD10–PLAP, and CD10–CD63 antibody pairs. Quality control was applied to ensure reproducibility. Group comparisons, correlation with gestational age, regression analyses, and ROC curves were performed. Serum CD63–PLAP counts were significantly elevated in EOPE compared with NP and LOPE, while plasma counts showed higher variability. Serum CD63–PLAP correlated negatively with gestational age in NP but not in EOPE. Stratification indicated that the discriminatory power of CD63–PLAP emerged after 100 gestational days. ROC analysis showed that CD63–PLAP distinguished EOPE from NP or non-EOPE with AUC ~ 0.74–0.75, achieving ~ 95% sensitivity at 385.55 sEV/µL, although specificity remained modest (~ 44%). The addition of CD10–CD63, maternal age, BMI, or gestational age did not substantially improve discrimination. These findings support serum CD63–PLAP measured by ExoCounter as a promising candidate biomarker for EOPE, showing moderate discrimination with high sensitivity but limited specificity in this Tanzanian cohort. Its low sample-volume requirement and operational simplicity support further evaluation, particularly in settings where conventional multiparametric screening is difficult to implement. Larger prospective studies with independent validation are required to confirm its discriminatory performance, establish clinically relevant thresholds, and assess its potential role in EOPE screening.

Source: Research Square

DOI: 10.21203/rs.3.rs-10667121/v1