TY - JOUR
T1 - Evaluation of a Flow Cytometry-Based Assay for Natural Killer Cell Activity in Clinical Settings
AU - Valiathan, R.
AU - Lewis, J. E.
AU - Melillo, A. B.
AU - Leonard, S.
AU - Ali, K. H.
AU - Asthana, D.
N1 - Copyright:
Copyright 2012 Elsevier B.V., All rights reserved.
PY - 2012/4
Y1 - 2012/4
N2 - Natural killer (NK) cells are not only important in first line defence against viral and bacterial infections, but also in immune surveillance of malignant cells and thus NK cell cytotoxicity is primary indicator of immune function. Although chromium release assay is recognized as 'gold standard' for measuring NK cell activity, it has disadvantages like use of radioactive compounds, poor loading and high spontaneous release. It is difficult to perform this assay in clinical laboratory because of difficulties with disposal of radioactive waste and standardization problems. We describe a flow cytometry-based assay for the measurement of NK cell activity by incorporating fluorescent dye, DiO, into membranes of target cells. NK cell activity was measured at baseline, 1 and 4weeks follow-up in 20 normal healthy individuals on a dietary supplement immunomodulator to enhance NK cell function. Mean baseline NK cell activity percentage (21.5; SD=9.3) increased significantly to a maximum level at 1week (31.3%; SD=7.9; P=0.007) and then returned to baseline level at 4weeks (21.5; SD=8.3). An important feature of flow cytometry-based assays is its ability to discriminate effector cells from target cells, and potential for explaining molecular interactions underlying target cell lysis. Under clinical settings, this assay will be of interest for frequently monitoring immunological status of patients on treatment for various diseases that affect their immune status. The assay is easy to perform without using radioactive material and thus could become a tool for monitoring pathogenesis and immune reconstitution.
AB - Natural killer (NK) cells are not only important in first line defence against viral and bacterial infections, but also in immune surveillance of malignant cells and thus NK cell cytotoxicity is primary indicator of immune function. Although chromium release assay is recognized as 'gold standard' for measuring NK cell activity, it has disadvantages like use of radioactive compounds, poor loading and high spontaneous release. It is difficult to perform this assay in clinical laboratory because of difficulties with disposal of radioactive waste and standardization problems. We describe a flow cytometry-based assay for the measurement of NK cell activity by incorporating fluorescent dye, DiO, into membranes of target cells. NK cell activity was measured at baseline, 1 and 4weeks follow-up in 20 normal healthy individuals on a dietary supplement immunomodulator to enhance NK cell function. Mean baseline NK cell activity percentage (21.5; SD=9.3) increased significantly to a maximum level at 1week (31.3%; SD=7.9; P=0.007) and then returned to baseline level at 4weeks (21.5; SD=8.3). An important feature of flow cytometry-based assays is its ability to discriminate effector cells from target cells, and potential for explaining molecular interactions underlying target cell lysis. Under clinical settings, this assay will be of interest for frequently monitoring immunological status of patients on treatment for various diseases that affect their immune status. The assay is easy to perform without using radioactive material and thus could become a tool for monitoring pathogenesis and immune reconstitution.
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U2 - 10.1111/j.1365-3083.2011.02667.x
DO - 10.1111/j.1365-3083.2011.02667.x
M3 - Article
C2 - 22150284
AN - SCOPUS:84863419965
VL - 75
SP - 455
EP - 462
JO - Scandinavian Journal of Immunology
JF - Scandinavian Journal of Immunology
SN - 0300-9475
IS - 4
ER -