Cord Blood Proteomic Biomarkers for Predicting Adverse Neurodevelopmental Outcomes in Monoamniotic Twins

Monoamniotic twins have a high risk of mortality and perinatal morbidity due to cord entanglement and vascular anastomosis. Despite efforts to reduce the mortality rate through intensive fetal surveillance and timed delivery, poor long-term neurodevelopmental outcomes remain an unsolved problem. This study aimed to identify novel biomarkers predicting abnormal neurodevelopmental outcomes in monoamniotic twins with cord blood samples taken at the time of delivery. Abnormal neurodevelopmental outcomes were defined as (1) a severe brain lesion on neonatal brain ultrasound, (2) developmental delay, (3) cerebral palsy, and/or (4) blindness or deafness. Cord blood was analyzed with mass spectrometry-based proteomics according to the neurodevelopmental outcomes. Statistical analysis was performed to determine the differentially expressed proteins between neonates with normal and abnormal neurodevelopmental outcomes. Several candidate proteins were further validated with enzyme-linked immunosorbent assays. A total of 20 neonates (10 pairs) of monoamniotic twins were included in the proteomic analysis, of which 25% had abnormal neurodevelopmental outcomes. Eighteen proteins were differentially expressed in neonates with abnormal neurodevelopmental outcomes. The upregulated proteins in the neonates with adverse neurodevelopmental outcome were immunoglobulin (Ig)-gamma-4 chain C region, apolipoprotein E, and alpha-fetoprotein. In contrast, Ig-lambda chain V region 4A, Ig-heavy variable 3, Ig-kappa chain C region, Ig-mu chain C region, C1q, ceruloplasmin, and Ig-lambda chain V-I region were decreased. In the validation experiment, the cord blood concentration of ceruloplasmin was significantly lower in neonates with adverse neurodevelopmental outcomes than in those without. Therefore, ceruloplasmin could be a useful predictive biomarker of adverse neurodevelopmental outcomes in monoamniotic twins.