Fig. 5.

Rituximab activated NK cells in vivo in patients with systemic inflammatory disease. PBMCs were isolated from blood withdrawn before and directly after rituximab (RTX) infusions from 15 patients (13 GPA, 1 eosinophilic GPA, and 1 rheumatoid arthritis). PBMCs were incubated with a panel of fluorochrome-labeled antibodies in order to determine percentages of B cells among lymphocytes (a-c) and the activation surrogate marker CD69 on NK cells (d-g) by flow cytometry. a, d Exemplary dot plots, all originating from the same patient receiving RTX for the first time. Statistical analysis of data from patients that received RTX for the first time (n = 9, 1st RTX; b, e) was performed separately from analysis from patients whose B cells were depleted due to prior rituximab infusions (n = 6, prior RTX; c, f), using Wilcoxon test. ns, not significant. g Direct comparison of patients receiving RTX for the first time or not, using one-tailed Mann-Whitney test. N = 6 per group; ΔCD69, (percentages of CD69+ NK cells after RTX) − (percentages of CD69+ NK cells before RTX); crossbars, means