Label-free enrichment of human adipose-derived stem cells using a continuous microfluidic sorting cascade

Human adipose tissue is a rich source of mesenchymal stem cells (MSCs). Human adipose-derived stem cells (ADSCs) are first prepared by tissue digestion of lipoaspirate. The remaining constituent contains a mixture of ADSCs, other cell types and lysed fragments. We have developed a scalable microfluidic sorter cascade which enabled high-throughput and label-free enrichment of ADSCs prepared from tissue-digested human adipose samples to improve the quality of purified stem cell product. The continuous microfluidic sorter cascade was composed of spiral-shaped inertial and deterministic lateral displacement (DLD) sorters which separated cells based on size difference. The cell count characterization results showed >90% separation efficiency. We also demonstrated that the enriched ADSC sub-population by the microfluidic sorter cascade yielded 6x enhancement of expansion capacity in tissue culture. The incorporation of this microfluidic sorter cascade into ADSC preparation workflow facilitates the generation of transplantation-scale stem cell product. We anticipate our stem cell microfluidic sorter cascade will find a variety of research and clinical applications in tissue engineering and regeneration medicine.

Automated summary

Human adipose tissue is a valuable source of mesenchymal stem cells (MSCs) and a microfluidic sorter cascade has been developed to enrich and purify adipose-derived stem cells (ADSCs) from tissue-digested samples. The sorter cascade utilizes spiral-shaped inertial and deterministic lateral displacement (DLD) sorters to separate cells based on size difference, resulting in a >90% separation efficiency. The enriched ADSC sub-population shows a 6x enhancement of expansion capacity in tissue culture. This microfluidic sorter cascade holds promise for various applications in tissue engineering and regeneration medicine.