Fig 2: WB data for RBP4 and KNG1 for patients who clinically recovered later than T3 according to sCr.Normalization of RPB4 levels was observed already at T3 on average (A,B) Individual RBP4 responses for those patients monitored at the three time points (solid lines represent patients with sCr(T3) > 1.3 mg/dL and dashed lines represent patients with sCr(T3) = 1.3 mg/dL). Inset shows representative behavior of RBP4 for patients who do not recover. **p value = 0.01.

Fig 3: (a) Chemiluminescence intensity measurements by aptasensor in the presence of different concentrations of RBP4 (From down to up: 0, 0.001, 0.025, 0.05, 0.1, 0.5, 1 and 2 ng/mL). (b) Calibration curve for determination of RBP4. Each point stands for the mean value of three independent experiments.

Fig 4: (a) Comparison between the chemiluminescence intensity obtained by aptamer/RBP4/luminol-antibody bearing intercross-linked gold nanoparticles (i) and aptamer/RBP4/luminol-antibody bearing gold nanoparticles (ii). In both tests the concentration of RBP4 was1 ng/mL. iii and iv are negative controls (Same as i and ii but, in the absence of RBP4) (b) Specificity of RBP4 biosensor towards different targets. Artificial serum was PBS containing 1 ng/mL of either main target (RBP4) or the other potentially interfering proteins: BSA, HSA, fibrinogen, insulin and anti-RBP4 antibody and vaspin.

Fig 5: Western blot data for RBP4 performed with individual urine samples.A different cohort of individuals to that used in DIGE analyses was recruited. On average, increased urinary levels for RBP4 (A) and decreased urinary levels for KNG1 (B) in response to AKI was confirmed: graphs show average data for all patients monitored (recovered at any time point or not). *p value = 0.05; **p value = 0.01; ***p value = 0.001; ****p value = 0.0001.