M. Zborowski et al., MAGNETIC FLOW SORTING USING A MODEL SYSTEM OF HUMAN-LYMPHOCYTES AND ACOLLOIDAL MAGNETIC LABEL, ASAIO journal, 42(5), 1996, pp. 666-671
Cells of identical physical properties that differ in the expression o
f surface proteins can be sorted conveniently using immunospecific sta
ins conjugated to fluorescent, or magnetic, labels. Immunomagnetic cel
l sorting using commercial batch sorters offers advantages of high sor
ting capacity, high viability of sorted fractions, and high depletion
rates; its disadvantages are low enrichment rate and batch processing.
The authors developed and tested a continuous, flow-through magnetic
cell sorter for small volume, experimental cell enrichment. Freshly is
olated human peripheral lymphocytes were labeled using an immunofluoro
magnetic sandwich consisting of mouse anti human CD8 monoclonal antibo
dy-fluorescein conjugate and rat anti mouse polyclonal antibody-colloi
dal iron-dextran conjugate. A total of 2-3 min lymphocytes were sorted
per hour using a saturation magnetic field of 1.334 T and a five chan
nel sorter. The fluorescent cells were distributed among the channels
in relation to their fluorescence intensity and magnetic susceptibilit
y. The purity (68-85%) and enrichment rates (16-34X) were comparable t
o those of commercial batch magnetic separators; sorting capacity and
recovery of the enriched fractions (up to 32%) were limited by the sma
ll scale of the sorter. Future direction is focused on increasing the
resolution, recovery, and sorting capacity of the enriched fractions,
and testing the sorter on other cell systems.