Isolation of HLA-G(+) cells using MEM-G/9 antibody-conjugated magnetic nanoparticles for prenatal screening: a reliable, fast and efficient method

The development of an effective and noninvasive early method for obtaining fetal cells is crucial to prenatal screening. Despite proving the presence of fetal cells in the reproductive tract, their use is limited due to their inability to properly isolate them from maternal cells. Magnetic-activated cell sorting (MACS) is a simple technique to separate cells. The present study aimed to develop a MACS-based platform for the isolation of the HLA-G expressing trophoblast cells. For this purpose, first, the triazine functionalized MNPs were synthesized and characterized. Then, MNPs were directly and indirectly conjugated by the MEM-G/9 antibodies targeting HLA-G(+) cells. The antibody amount on the surface of the nanoparticles was determined with the Bradford assay. The cell capture efficiency was also investigated. Various characterization methods confirmed the successful nanoparticle synthesis and antibody conjugation. The optimal initial antibody amount for the immobilization was about 20 μg and the optimal time was 3 h. The antibody-nanoparticles by the indirect method had better targeting and capture efficiency than the direct method. The MNPs indirectly conjugated with antibodies are an efficient tool for cell isolation and present considerable potential to be applied in biomedical fields.