A tag-less method of sorting stem cells from clinical specimens and separating mesenchymal from epithelial progenitor cells.
BACKGROUND
The interest in stem cell (SC) isolation from easily accessible clinical specimens is booming. The lack of homogeneity in pluri/multipotent SC preparation blurs standardization, which however is recommended for successful applications. Multipotent mesenchymal SCs (MSCs) in fact express a broad panel of surface antigens, which limit the possibility of sorting homogeneous preparations by using an immunotag-based method.


METHODS
We present a tag-less, flow-assisted method to purify, distinguish, and sort pluri/multipotent SCs obtained from clinical specimens, based on differences in the biophysical properties that cells acquire when in suspension under fluidic conditions. A suspension of cells in a transport fluid is injected into a ribbon-like capillary device by continuous flow. In a relatively short time (about 30 min), sorted cells are collected.


RESULTS
We obtained baseline separation between MSCs and epithelial cells, which are important contaminants of isolated MSCs. The extent of separation is evaluated by flow cytometry through detection of a specific epithelial antigen. MSCs from various human sources also prove to have different, characteristic, highly-reproducible fractionation profiles. Finally, we evaluated the dissimilar differentiation potential among cell fractions obtained from sorting a single MSC source. After differentiation induction, a fraction displayed a differentiation yield close to 100%, whereas unfractionated cells contained only 40% of responding cells.


CONCLUSIONS
The results demonstrate that the method presented is able to obtain selected and well-characterized living MSCs with an increased differentiation yield. Its reduced cost, full biocompatibility, and scale-up potential could make this method an effective procedure for stem cell selection.
Department of Chemistry G. Ciamician, University of Bologna, via Selmi 2, I-40126 Bologna, Italy.
Barbara
B
Roda
Pierluigi
P
Reschiglian
Andrea
A
Zattoni
Francesco
F
Alviano
Giacomo
G
Lanzoni
Roberta
R
Costa
Arianna
A
Di Carlo
Cosetta
C
Marchionni
Michele
M
Franchina
Laura
L
Bonsi
Gian Paolo
GP
Bagnara
D050156:Adipogenesis / Q000502:physiology; D018929:Cell Culture Techniques / Q000379:methods; D002454:Cell Differentiation / Q000502:physiology; D002469:Cell Separation / Q000379:methods; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000166:cytology* / Q000502:physiology; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D013048:Specimen Handling; D013194:Staining and Labeling; D013234:Stem Cells / Q000166:cytology*