Evaluation of CD56^dimCD16⁺ NK frequency in NHL patient PB before and after vaccination. (A) Ratios of CD56^dimCD16⁺ NK frequencies in postvaccination versus prevaccination PB samples of responders and nonresponders.(B) Ratios of CD16 MFI in NK cells of postvaccination versus prevaccination PB samples of responders and nonresponders. Statistically significant differences were calculated using the Fisher exact test (**P ≤ .01). (C) Representative examples of CD56^dimCD16⁺ NK frequencies in prevaccination versus postvaccination PB of a complete responder (left panels, patient no. 14), and of a nonresponder (right panels, patient no. 7). All plots were gated on CD3⁻CD56⁺ cells. Data were acquired using BD CellQuest software version 3.3 on the 4-color analysis flow cytometer BD FACSCalibur. Analyses were performed using FlowJo 8.7.1 software version for Macintosh.