High-purity isolation of rare single cells from blood using a tiered microchip system

Abstract

We present a two-tiered microchip system to capture and retrieve rare cells from blood samples with high purity. The first module of the system is a high throughput microfluidic interface that is used to immunomagnetically isolate targeted rare cells from whole blood, and discard > 99.999% of the unwanted leukocytes. The second module is a microwell array that furthers the purification by magnetically guiding each cell into a separate well concurrently, and allows individual retrieval of each cell. We demonstrate the design of the system as well as its characterization by experiments using model cell lines that represent circulating fetal trophoblasts. Our results show that single cells can be retrieved with efficiencies and purities as high as 100% within 145 mins.

Overview and recent developments in cell‐based noninvasive prenatal testing

“…spiked blood samples with JEG3 cells, a choriocarcinoma cell line which expresses EVT markers. Immunomagnetic selection based on EpCAM and HLA‐G through a two‐tiered microchip system, resulted in high purity JEG3 cell recovery 89 . Vander Plaetsen and colleagues recently tested the VTX‐1 Liquid Biopsy system, which uses laminar microscale vortices for size‐based trophoblast isolation, and recovered 2–6 trophoblasts from 8 ml of blood in 7/10 women carrying male pregnancies 91 …”

“…More recently, several commercial and academic groups have explored microfluidics platforms (originally developed for CTC isolation) for cbNIPT applications, with variable success. These rare cell isolation platforms capture trophoblasts by immunomagnetic enrichment, 88,89 size-based selection 90,91 or specific dielectrophoretic separation, 92 although for some only proof-of-principle data is available. Compared to manual processing, these platforms require lower sample volumes and less cell manipulation, and their approach for cell enrichment is often less harsh, lowering the risk for cell loss or inadequate cell quality.…”

Prenatal Diagnosis: The Main Advances in the Application of Identification of Biomarkers Based on Multi-Omics

“…Maternal serum screening could be used as a routine prenatal test to determine the risk of aneuploidies as well as certain malformations, including NTDs [8,9]. Maternal serum screening was classically done in the second trimester but now first-trimester screening has also been found equally useful [8].…”

“…First detected in cancer patients' sera in 1948 [12], cfDNA, used as a prognostic factor in malignant disease [9,13], has gradually shown some advantages in the application of prenatal diagnosis since Lo et al detected circulating fetal DNA in maternal plasma in 1997 [9,14]. With the rapid advances in molecular biological technologies, it creates a preferable procedure for chromosomal abnormalities and monogenic disorders.…”

Isolation and Enrichment of Circulating Fetal Cells for NIPD: An Overview

“…In a recent study, Gur et al presented a two-tiered microchip system that reduces sample preparation steps while implementing purity, using ETVs model cell lines. The system allows for direct processing of a whole blood sample and appears versatile enough to target a variety of antigens to achieve a high rate of cell recovery [ 81 ].…”