Cytotoxicity Assay - (May/14/2007 )

Hi,
I am trying to assess cytotoxicity of NK cells using G-K562 cells. My question is:
- Does the medium volume during culture stimulation affect the cytotoxicity?? i.e., if I culture effector and target X number of cells in 500 ul, does it give the same result if I cultur the same number of cells in 1000 ul???
Thanks.

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I think the change in osmolality could affect your cells. Are concentrations of solutes maintained between the two volumes? Also, there may be an issue of buffer capacity depending on how many cells you have. All things being equal (well, ratio really) provided there is sufficient buffer capacity in the volume you use I think your cells will be fine.

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I am not familiar with the cell lines: are they adherent or non-adherent?

in the case of non-adherent cells, important are the concentrations of the cells; if you increase the volume you should increase the cell number;

in the case of adherent cells, higher volumes of medium may affect pressure of O2 of the medium

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Hi all,
thank you for your replies.
Actually, the cells I am using are not adherent. The NK cells and the K562 cells are cultured in RPMI medium. I cultured 8x10*4 NK cells with 5x10*3 Target cells (E:T 16:1) in 1000 ul, and I cultured the same cell numbers in 500 ul, should the cytotoxic activity be the same under this conditions??
Thanks.

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at first glance I suppose that the same cell numbers in 1000 µl is a dilution compared to 500 µl, and may not give the same results; in the end, you have to prove it by experiments...

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