A Novel Method for Placental Evaluation: Isolation of Intact Circulating Trophoblast Cells from Maternal Circulation
This Society for Maternal-Fetal Medicine 2024 poster reports a RareCyte liquid-biopsy workflow that isolates individual, intact circulating trophoblasts from a maternal blood draw across a third-trimester cohort — a foundational step toward transcriptional profiling of placental cells to study adverse pregnancy outcomes.
Presented by Swedish Medical Center.
Read or download to see:
- An enrichment-to-isolation workflow recovers individual, intact circulating trophoblasts from maternal blood. Nucleated cells are collected from whole blood with the AccuCyte system and immunomagnetically bead-enriched, then transferred to slides and stained with a four-marker immunofluorescence panel — Hoechst for the nucleus, pan-cytokeratin and TMX as trophoblast markers, and CD45 to exclude white blood cells; candidate cells are imaged on CyteFinder instruments and retrieved individually with the CytePicker module.
- Candidate trophoblasts were recovered across a 22-participant third-trimester cohort. In blood from 22 singleton pregnancies — most uncomplicated at the time of the draw — candidate circulating trophoblasts were enumerated per roughly 30 mL of blood, ranging from 0 to 17 per participant, and were scored alongside hybrid and indeterminate cells captured on the same slides.
- Cytokeratin-positive cells are classified into three marker-defined types. Candidate trophoblasts were defined as CD45-negative and cytokeratin-positive, hybrid cells as CD45-positive and cytokeratin-positive, and indeterminate cells as CD45-negative, cytokeratin-positive events with uncharacteristic cellular features — a scheme the authors present as the foundation for later transcriptional profiling of the isolated cells.
