LDH assay confirms that cell death in the presence of 1% Triton X-100 is proportional to the number of cells in the well

LDH assay confirms that cell death in the presence of 1% Triton X-100 is proportional to the number of cells in the well. K562 cells were titrated in 96-well plates at the indicated cell concentrations. The reaction mixture was added to confirm that the spontaneous release of LDH is low. In the presence of the reaction mixture plus Triton X-100 (final concentration 1%), LDH release increased proportionally to cell concentration, based on measurements of formazan absorbance at 492 nm.

Using the LDH assay to measure the cytolytic activity of allogen-stimulated, cytotoxic T lymphocytes

Using the LDH assay to measure the cytolytic activity of allogen-stimulated, cytotoxic T lymphocytes. Spleen cells of C57/Bl 6 mice (H-2b) were stimulated in vitro with P815 cells (H-2d). Viable cytotoxic T lymphocytes (CTLs) were purified by ficoll density gradient, washed and titrated in a 96-well plate. 1 × 104 P815 test cells/well were added to the effector CTL cells. The cell mixture was centrifuged and incubated for 4 hr. 100 μl of culture supernatant was collected for the LDH assay. Panel A. Absorbance values for the effector cell control (orange), effector-test cell mix (blue), and effector-test cell mix minus effector cell control (red). Panel B. Percent cell-mediated cytotoxicity.

Principle of measurement of LDH cytotoxicity

Principle of measurement of LDH cytotoxicity.

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