MarrowCellDLD: a microfluidic method for label-free retrieval of fragile bone marrow-derived cells

Area of Science:

• Biomedical Engineering
• Cell Biology
• Hematology

Background:

• Limited knowledge exists on fragile bone marrow cell populations beyond hematopoietic progenitors, including bone marrow adipocytes (BMAds) and megakaryocytes.
• Isolation of these large, fragile cells is challenging due to their susceptibility to rupture and size.

Purpose of the Study:

• To introduce MarrowCellDLD, a novel label-free cytometry microsystem for isolating large, fragile bone marrow-derived cells.
• To demonstrate the system's ability to preserve cell viability and functionality during isolation.

Main Methods:

• Utilized deterministic lateral displacement (DLD) in a microfluidic system (MarrowCellDLD) for label-free cell isolation.
• Validated the system using mouse and human bone marrow adipocytes and human megakaryocytes derived from CD34+ hematopoietic stem and progenitor cells.
• Employed real-time imaging for quality control and sorted cells directly in culture media without pre-labeling.

Main Results:

• MarrowCellDLD successfully isolated large, fragile BM-derived cells based on intrinsic size properties, preserving viability and functionality.
• Achieved precise micrometer-range separation cutoffs adapted for specific cell types (BMAds, megakaryocytes).
• Outperformed two fluorescence-activated cell sorting (FACS) instruments in purity and yield, especially for large cell fractions, retrieving at least 10^6 intact cells per round.

Conclusions:

• MarrowCellDLD is an effective non-destructive sorting tool for large, fragile bone marrow-derived cells.
• Facilitates the separation of pure populations of bone marrow adipocytes and megakaryocytes.
• Enables further investigation into the physiological and pathological roles of these critical cell types.