Human lymphocyte sorting by gravitationa field-flow fractionation

The interest in biological studies on various cell types for many biomedical applications, from research to patient treatments, is constantly increasing. The ability to discriminate and/or quantify (sort) distinct subpopulations of cells has then become increasingly important. For instance, not only detection but also the highest depletion of neoplastic cells from normal cells is an important requisite in the autologous transplantation of lymphocytes for blood cancer treatments. In this work, gravitational field-flow fractionation (GrFFF) shows effective for sorting a heterogeneous mixture of human, living lymphocytes constituted of neoplastic B cells from a Burkitt lymphoma cell line and of healthy T and B lymphocytes from blood samples. GrFFF does not require the use of fluorescent immuno-tags for sorting cells, and the sorted cells can be collected for their further characterization. Flow cytometry (FC) is used to assess viability of the collected cells, and to evaluate the obtained cell fractionation. A low amount in neoplastic B lymphocytes (<2%) is found in a specific fraction obtained by GrFFF. The high depletion from neoplastic cells (>98%) is finally confirmed by clonogenicity test.