High gradient magnetic cell separation with MACS

TLDR

Developed and tested a flexible, fast, and simple magnetic cell sorting system for separating large numbers of cells according to specific surface markers. Cells are sequentially stained with biotinylated antibodies, fluorochrome‑conjugated avidin, and ~100 nm superparamagnetic biotinylated microparticles, then passed through high‑gradient magnetic columns where unlabeled cells flow through and labeled cells are retained. The system processes >10⁹ cells in ~15 min, achieving >100‑fold enrichment and >1,000‑fold depletion while preserving cell viability, proliferation, and fluorescence characteristics, enabling downstream flow cytometry or sorting.

Abstract

Abstract A flexible, fast and simple magnetic cell sorting system for separation of large numbers of cells according to specific cell surface markers was developed and tested. Cells stained sequentially with biotinylated antibodies, fluorochrome‐conjugated avidin, and superparamagnetic biotinylated‐microparticles (about 100 nm diameter) are separated on high gradient magnetic (HGM) columns. Unlabelled cells pass through the column, while labelled cells are retained. The retained cells can be easily eluted. More than 10 9 cells can be processed in about 15 min. Enrichment rates of more than 100‐fold and depletion rates of several 1,000‐fold can be achieved. The simultaneous tagging of cells with fluorochromes and very small, invisible magnetic beads makes this system an ideal complement to flow cytometry. Light scatter and fluorescent parameters of the cells are not changed by the bound particles. Magnetically separated cells can be analysed by fluorescence microscopy or flow cytometry or sorted by fluorescence‐activated cell sorting without further treatment. Magnetic tagging and separation does not affect cell viability and proliferation.