Kobe University Repository : Kernel タイトル Tit le Comparison of venous and fingert ip plasma using non-targeted proteomics and metabolomics

26 Blood tests, which are used to evaluate health status, are relatively non-invasive and 27 provide a great deal of health-related information. Blood is usually collected using a 28 standard venous blood sampling protocol, but it is possible to collect blood from a 29 subject’s fingertip, and previous studies have investigated whether fingertip-derived 30 blood can be used for various blood tests. In this study, the proteomes and metabolomes 31 of venous and fingertip plasma were analyzed using non-targeted proteomics and 32 metabolomics, respectively. In proteomics, the levels of 523 proteins were compared 33 between venous and fingertip plasma. The correlation coefficient (r) for the relationship 34 between protein levels of venous and fingertip plasma was 0.9999. Some proteins had 35 high fingertip to venous plasma level ratios (finger:venous ratios), whereas others had 36 low finger:venous ratios, and the mean±standard deviation (SD) finger:venous ratio was 37 0.994±0.304. In metabolomics, 40, 33, and 216 cationic metabolites, anionic 38 metabolites, and lipids, respectively, were detected in venous plasma, and the equivalent 39 figures for fingertip plasma were 40, 35, and 216, respectively. Regarding the 40 correlations between metabolite levels in venous and fingertip plasma, the correlation 41 coefficients (r) for cationic metabolites, anionic metabolites, and lipids were 0.9952, 42 0.9699, and 0.9980, respectively. The mean±SD finger:venous ratio was 1.19±0.584 for 43 cationic metabolites, 1.23±0.548 for anionic metabolites, and 1.00±0.245 for lipids. Our 44 study suggests that it might be possible to use fingertip plasma to measure plasma 45 protein and metabolite levels, and will contribute to development of a fingertip blood 46 sampling procedure for measuring blood biomarker levels. 47