Fig. 5

Rituximab (RTX) leads to further phenotypical changes in CD56^dim natural killer (NK) cells. Freshly isolated peripheral blood mononuclear cells (PBMCs) were incubated with (+) or without (w/o) RTX overnight. The next day PBMCs were stained with a mixture of antibodies (anti-CD3 PE-Dazzle, anti-CD56 Bv421 and anti-CD16 FITC and CD69/CD137 PE) and analyzed by flow cytometry. NK cells were identified as CD3-CD56+ cells in the lymphocyte gate and fluorescence intensity of PE on CD56^dim NK cells was measured. a CD69 PE. Histogram shows one representative donor; gray incubation + RTX, black w/o RTX. Left diagram mean CD69 PE fluorescence intensity in samples from 13 donors. Statistical significance was determined with the Wilcoxon signed rank test (p = 0.0002). Right diagram Δ % in CD56^dim NK was determined by (CD69-positive CD56^dim NK cells after incubation + RTX) - (CD69-positive CD56^dim NK cells after incubation w/o RTX); bar median. b CD137(41BB)-PE; same donor, layout and abbreviations as in a; n = 11 donors; p = 0.001