Fig. 1

Expression of CXCR2 on NK cells and its ligands on RCC tumors. a Expression of CXCR2 ligands in the plasma and tumor lysate of patients with primary RCC relative to mg total protein (n = 14). Samples were analyzed using Bio-Plex Pro Human Chemokine 40-plex panel. b Expression of CXCR2 ligands by primary low-passage (P1 or P3) RCC cell lines. CXCL1 production by TINCA3 and TINCA7 as well as CXCL8 production by TINCA3 were above the quantification limits of 13,990 pg/mL and 31,093 pg/mL, respectively. c Pearson correlation of CXCL5 levels in tumor lysate in patients with primary RCC and frequency of intratumoral CXCR2-positive NK cells (n = 9). d Frequency and (e) levels of CXCR2 expression by NK cells in peripheral blood (PB) and primary tumors of RCC patients (n = 13). A representative histogram from patient RCC007 is shown. f Flow cytometry analysis of CXCR2 expression by healthy donor peripheral blood non-activated NK cells and eight-day expanded NK cells. Results are representative of four experiments