Sterile sorting of Leu-11a-positive cells (NK cells) using flow cytometry and the antineoplastic effects on brain...

Though we recently found some reports on sterile sorting of natural killer cells (NK cells) by flow cytometer (FCM), which manifested cytotoxicity, no reports have concerned antineoplasticity of sterile NK cells on glioma cell lines and cultured surgical materials of brain tumor so far as we know. Monocytes were sampled from the peripheral blood of healthy adults, stained with fluorescein isothiocyanate (FITC)-labeled antihuman monoclonal antibodies, and sorted by an FCM, which had been sterilized with 0.5% Hibitane alcohol solution. Over 95% of the cells obtained were NK cells, and their viability was disclosed to be 97% by the FDA staining. Using thus obtained NK cells, the antineoplastic effects were evaluated in 3 kinds of glioma cell lines and 5 surgical specimens by the microcytotoxicity test. The effects varied widely from 9 to 74% (E/T ratio 40) for glioma cell lines, and from 1 to 66% (E/T ratio 10-40) for surgical specimens. It is expected in the future to apply NK cells clinically using this sterile sorting technique.