Project Summary/Abstract:
Spontaneous preterm labor (PTL, <37 weeks gestation) is the leading cause of neonatal and infant
mortality globally, representing ~60% of all infant deaths. The physiopathology of PTL remains poorly
understood due to the heterogeneities associated with the risk factors including maternal age, multiple
gestation, and co-morbidities among others. Current clinical standard to identify women at high risk of PTL
include cervical length assessment, and screening for fetal fibronectin in the cervicovaginal fluid. However,
these approaches are inadequate and often fail to identify women who may deliver preterm. Recent patient
metadata studies have identified multiple biomarkers correlated to PTL but risk scoring based on single
biomarkers has shown low positive predictive values and have been ineffective in PTL prediction. The
scientific premise of the proposed study is that there is an urgent clinical need for accurate diagnostics with
multiplexed biomarker detection capabilities that are simultaneously affordable to facilitate routine bedside
screening for all patients. Further by benchmarking the biodiagnostic against commercial assays using the
same sample type from the same patients will minimize inter- and intra-assay variation, which remains a
challenge in current bedside diagnostics.
The objective of this study is to address this unmet need with an innovative biodiagnostic, PRADA,
which combines high sensitivity, specificity, multiplexing, use of low sample volumes, and low cost. PRADA,
portable reusable accurate diagnostics with nanoantennas, consists of magnetic microbeads capture probes
functionalized with polyclonal antibodies, and near-infrared resonant gold nanostar “antennas” barcoded with
Raman tags and labeled with peptides to detect the biomarkers via surface-enhanced Raman spectroscopy
(SERS). PRADA has successfully demonstrated multiplexed detection of 3 PTL biomarkers including alpha-
fetoprotein (AFP), corticotrophin releasing hormone (CRH) and granulocyte macrophage colony-stimulating
factor (GM-CSF) in pregnant patient serum. PRADA achieved ultrasensitive limit of detection (LOD, 1.7 pg/ml
GM-CSF) ideal for risk stratification, and when compared to commercial Luminex and ELISA, PRADA showed
far lower LODs. Further, PRADA is also reusable (due to the use of magnetic beads), lowering the overall cost
by allowing >15 uses of a single microfluidic device. This work will leverage innovative PRADA to
quantitatively detect 6 serum biomarkers which are the most predictive of PTL including C-reactive protein
(CRP), AFP, IL-10, IL-6, CRH, and GM-CSF benchmarked against Luminex and ELISA (Aim 1). Further, we
will validate multiplexing with PRADA in serum of patients recruited for this study in the 18 – 35 years age
group with singleton pregnancy and gestation age 19 – 36 weeks (Aim 2). A maternal risk score will be
established categorizing patients into high and low risk groups, and the scoring will be compared to their
existing diagnosis to determine the accuracy of PRADA. Our central hypothesis is PRADA will enable a
robust bedside diagnosis that accurately predicts the onset of PTL, identifies patients who need immediate
treatment, and minimizes unnecessary intervention for those at low risk.
PRADA is clinically translatable as gold nanoparticles are already in clinical trials (NCT00436410,
NCT00356980) and integrated in commercial assays (First response pregnancy tests), and SERS has
demonstrated utility in commercial sensors (Oxonica, Renishaw Diagnostics etc.). This impactful project will
leverage the expertise of the PI (Bardhan) in nanoparticle diagnostics and SERS, with the complementary
expertise of co-investigators Dr. Leon Bellan (microfluidics), Dr. Jeff Reese (mechanisms of PTL), and Dr. J.
Michael Newton (PTL patient treatment).