Stability of Proteins in Dried Blood Spot Biobanks

• An important motivation for the construction of biobanks is to discover biomarkers that identify diseases at early, potentially curable stages. This will require biobanks from large numbers of individuals, preferably sampled repeatedly, where the samples are collected and stored under conditions that preserve potential biomarkers. Dried blood samples are attractive for biobanking because of the ease and low cost of collection and storage. Here we have investigated their suitability for protein measurements. 92 proteins with relevance for oncology were analyzed using multiplex proximity extension assays (PEA) in dried blood spots collected on paper and stored for up to 30 years at either +4°C or -24°C.</p> <p>Our main findings were that 1) the act of drying only slightly influenced detection of blood proteins (average correlation of 0.970), and in a reproducible manner (correlation of 0.999), 2) detection of some proteins was not significantly affected by storage over the full range of three decades (34% and 76% of the analyzed proteins at +4°C and -24°C, respectively), while levels of others decreased slowly during storage with half-lives in the range of 10 to 50 years, and 3) detectability of proteins was less affected in dried samples stored at -24°C compared to at +4°C, as the median protein abundance had decreased to 80% and 93% of starting levels after 10 years of storage at +4°C or -24°C, respectively. The results of our study are encouraging as they suggest an inexpensive means to collect large numbers of blood samples, even by the donors themselves, and to transport, and store biobanked samples as spots of whole blood dried on paper. Combined with emerging means to measure hundreds or thousands of protein, such biobanks could prove of great medical value by greatly enhancing discovery as well as routine analysis of blood biomarkers.

Ämnesord

Medical and Health Sciences  (hsv)

Clinical Medicine  (hsv)

Clinical Laboratory Medicine  (hsv)

Medicin och hälsovetenskap  (hsv)

Klinisk medicin  (hsv)

Klinisk laboratoriemedicin  (hsv)

Nyckelord

Absolute quantification

Affinity proteomics

Biobanking

Bioinformatics splicing

Biomarkers

Blood*

DBS

Diagnostic

Dried Blood Spot

Multiplex protein detection

PCR

Plasma or serum analysis

Predictive markers*

Protein Stability

Proximity Extension Assay