Fig. 1.

Expression and function of Siglecs in NK cells from healthy donors and patients with bladder cancer. (A) Flow cytometry measurement of CD107a on NK cells from PBMCs from HDs after co-culture with untreated or desialylated T24 or TCC-Sup bladder tumor cells at an E/T ratio of 1:4. Representative FACS histograms of (B) Siglec-6 and (C) Siglec-7 expression levels and their quantification in NK cells from peripheral blood of HDs (black line; n = 9), NMIBC patients (green line; n = 12), and MIBC patients (red line; n = 12). Representative FACS histograms of (D) Siglec-6 and (E) or Siglec-7 expression levels and their quantification in tumor-infiltrating NK cells from NMIBC patients (green line; n = 4) and MIBC patients (red line; n = 4). Representative FACS histograms of (F) Siglec-6 and or (G) Siglec-7 expression levels and their quantification in in vitro expanded urinary NK cells from NMIBC patients undergoing BCG therapy at post-BCG2 (light blue; n = 7) and post-BCG5/6 (light red; n = 10–12). Data are presented as the mean ± standard error of the mean. Values are expressed as the ratio of mean fluorescence intensity for specific staining versus the isotype Ig control (RFI). The dotted line represents the detection limit. BCG = bacillus Calmette-Guérin; E/T = effector/target; FACS = fluorescent-activated cell sorting; HD = healthy donor; MIBC = muscle-invasive bladder cancer; NK = natural killer; NMIBC = non–muscle-invasive bladder cancer; PBMC = peripheral blood mononuclear cell; TINK = tumor-infiltrating NK cell; Siglec = sialic acid–binding immunoglobulin-like lectin. * p < 0.05; ** p < 0.01.