Capillary blood self‐collection for high‐throughput proteomics

In this study, we sought to compare protein concentrations obtained from a high‐throughput proteomics platform (Olink) on samples collected using capillary blood self‐collection (with the Tasso+ device) versus standard venipuncture (control). Blood collection was performed on 20 volunteers, including one sample obtained via venipuncture and two via capillary blood using the Tasso+ device. Tasso+ samples were stored at 2°C–8°C for 24‐hs (Tasso‐24) or 48‐h (Tasso‐48) prior to processing to simulate shipping times from a study participant’s home. Proteomics were analyzed using Olink (384 Inflammatory Panel). Tasso+ blood collection was successful in 37/40 attempts. Of 230 proteins included in our analysis, Pearson correlations (r) and mean coefficient of variation (CV) between Tasso‐24 or Tasso‐48 versus venipuncture were variable. In the Tasso‐24 analysis, 34 proteins (14.8%) had both a correlation r > 0.5 and CV < 0.20. In the Tasso‐48 analysis, 68 proteins (29.6%) had a correlation r > 0.5 and CV < 0.20. Combining the Tasso‐24 and Tasso‐48 analyses, 26 (11.3%) proteins met these thresholds. We concluded that protein concentrations from Tasso+ samples processed 24–48 h after collection demonstrated wide technical variability and variable correlation with a venipuncture gold‐standard. Use of home capillary blood self‐collection for large‐scale proteomics should be limited to select proteins with good agreement with venipuncture.