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Updated: Aug 19, 2026

Quantitative Imaging of Lineage-specific Toll-like Receptor-mediated Signaling in Monocytes and Dendritic Cells from Small Samples of Human Blood
Published on: April 16, 2012
Monocytes are responsible for depressed natural killer (NK) activity in both young and elderly low NK responders
J Myśliwska1, A Myśliwski, P Romanowski
1Department of Histology, Medical School, Gdańsk, Poland.
Abstract:
Two age groups--young (19-35) and elderly (70-91)--were compared with respect to natural killer (NK) cytotoxic activity. In both groups, low and high NK responders could be distinguished. Low NK responders constituted about 70% of all elderly and 40% of young individuals. The differences in the magnitude of NK activity among the young and elderly groups could only be observed when peripheral-blood mononuclear cells but not peripheral-blood lymphocytes were used as effector cells in a 51Cr release assay. Experiments with removal or addition of graded numbers of monocytes showed that these cells were responsible for the low level of NK activity in both the young and elderly low NK responders.
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