Fig 2: CXCL16 and CXCR6 expression do not differ between primary tumour and metastases. (A) Representative examples of CXCL16 and CXCR6 staining. (I) CXCL16 weak, (II) CXCL16 strong, (III) CXCR6 weak, (IV) CXCR6 strong. (B) CXCL16 score between primary OC and omental tissue. (C) CXCR6 score between primary OC and omental tissue.

Fig 3: ADAM proteases regulate CXCL16 shedding. (A) Representative picture of CXCL16, ADAM-10, and ADAM-17 staining on the OC cell line A2780 as determined by fluorescent imaging (performed on PFA fixed cells) and western blot analysis. Conjugate controls were included to determine background fluorescence. (B) Levels of CXCL16 were determined on the OC cell line A2780 with or without TAPI-2/GI254023x (100 μM) treatment, using confocal microscopy, flow cytometry, and western blot analysis. Of note, MFI of conjugate control used in flow cytometric analysis was 21 000. (C) Analysed CXCL16 levels (corrected total cell fluorescence (CTCF)) on A2780 cells (n=4) with or without TAPI-2/ GI254023x (100 μM) treatment. Conjugate control (Alexafluor-488 Donkey anti-Goat) was used to determine background fluorescence. (D) Analysed ADAM-10 and ADAM-17 expression levels (CTCF) and background fluorescence with conjugate control on a small panel or primary derived OC cells (n=6). Depicted confocal images are a representative of ADAM-10 and ADAM-17 staining in primary OC. (E) Analysed CXCL16 levels (CTCF) on primary OC (n=11) with or without TAPI-2 treatment (100 μM). Depicted confocal images are a representative of CXCL16 fluorescent staining on medium and TAPI-2-treated primary OC cells. (F) Analysed CXCL16 levels (CTCF) on primary OC (n=7) with or without GI254023x treatment (100 μM). Depicted confocal images are a representative of CXCL16 staining on medium and GI254023x-treated primary OC cells. (G) sCXCL16 levels in supernatants of untreated vs TAPI-2/ GI254023x-treated (100 μM) A2780 cells. (H) sCXCL16 levels in supernatants of untreated vs TAPI-2 (100 μM)-treated primary OC cells (n=10). TAPI-2 inhibits 43.9% of all sCXCL16 release on average. (I) sCXCL16 levels in supernatants of untreated vs GI254023x (100 μM)-treated primary OC cells (n=6). GI254023x inhibits 89.7% of all sCXCL16 release on average.

Fig 4: Correlations between circulating CXCL16 levels and SAPS II score on the first POD. Data are depicted as linear regression (black line) with 95% confidence intervals (long dashed line).

Fig 5: Surgery induced circulating CXCL16 as chemotactic stimulus. (A) Surface expression of CXCR6 on lymphocytes and monocytes of freshly isolated PBMCs of healthy volunteers (black line: anti‐CXCR6; grey line: isotype). Shown are representative histograms of three independent PBMC isolations. (B) PBMC were subjected to chemotaxis against 3 nM recombinant CXCL16 using a transwell system. (C) Comparison of the chemotactic potential of serum from patients before surgery and after termination of surgery (each n = 5). Freshly isolated PBMC were used in a transwell system using 10% serum as chemotactic stimulus. The contribution of circulating CXCL16 to the chemotactic potential was shown by a CXCL16‐neutralizing antibody (anti‐CXCL16) in comparison to the isotype control. (B/C) Shown are mean values ± S.E.M. Significance was calculated using one‐way anova and Dunnet post‐test (**P < 0.01, all versus w/o stimulus in B and w/o antibody in C) and Student's t‐test.