Fig 1.
Reference curve of the survivin spPLA based on 40 independent experiments.
Survivin concentrations ranged from 0.32 pg/mL to 5000 pg/mL. (a) Raw Ct-values versus survivin concentrations. (b) Delta Ct-values versus survivin concentrations. (c) Comparison of spPLA (solid) and ELISA (dotted, mean of 44 independent experiments) for survivin detection.
Fig 2.
Workflow for spPLA detection of survivin in urinary samples.
After urine concentration the remaining sample is diluted in buffer for pH neutralization. After sequential binding of survivin antibody-functionalized magnetic beads and proximity probes, DNA-strands come into close proximity. A connector allows the ligation, thereby forming a new chimeric DNA strand. Real-time PCR and further analysis allow protein quantification.
Table 1.
Comparison of different cutoffs for the surviving spPLA.
Fig 3.
Group analysis of spPLA survivin measurements.
Detectable amounts of survivin are depicted as dot plots on a logarithmic scale for cases and clinical controls with median and range. Samples containing no measurable amounts of survivin are indicated with 0*. LoD: Limit of detection.
Fig 4.
Venn diagram for survivin spPLA and UBC Rapid for both groups, cases and clinical controls.
The cutoff for the spPLA was 1.45 pg/mL, resulting in 33 positive cases and 14 positive clinical controls. The cutoff for UBC Rapid assay was set to 10 mg/L, resulting in 61 positive cases and 5 positive clinical controls.