CD56^bright NK cells have a higher cytotoxic potential towards activated CD4⁺ T cells.

Abstract

<p>Autologous NK cells and CD4⁺ T cells were isolated, and CD4⁺ T cells were activated for 4 days as described. NK cells were activated as indicated: 200 IU/mL IL-2, 25 ng/mL IL-4, 25 ng/mL IL-7, 25 ng/mL IL-9, 5 ug/mL IL-15, 100 ug/mL IL-21, 50 ug/mL IL-12, 0.25 mg/mL IL-18 or 100 U/mL IFN-αA. NK cells and CD4⁺ T cells were co-cultured for 4 hours with FITC-conjugated anti-CD107a+anti-CD107b antibodies. Flow cytometry was performed to determine degranulation of (A) CD56^dim NK cells and (B) CD56^bright NK cells. Data represent mean ± SEM of n≥4 experiments. Statistical significance is calculated in comparison to resting NK cells (media) co-cultured with activated CD4⁺ T cells. * <i>P</i><0.05, ** <i>P</i><0.005, *** <i>P</i><0.001.</p