Dried Blood and Serum Spots As A Useful Tool for Sample Storage to Evaluate Cancer Biomarkers
June 11th, 2018
10.1K views
This protocol describes a simple and useful method to store peripheral blood and serum/plasma for downstream analyses such as single nucleotide polymorphism (SNP) evaluation and ELISA assay.
Overview
This protocol describes a method to store peripheral blood and serum/plasma for downstream analyses such as SNP evaluation and ELISA assay. It allows for the storage of samples for at least two weeks without freezing, ensuring high-quality material for various analyses.
Key Study Components
Area of Science
- Translational research
- Biomarker analysis
- Diagnostic methods
Background
- This method addresses the need for sample storage in developing countries.
- It provides a solution for studying biomarkers when frozen samples are unavailable.
- Visual demonstration is critical for learning the blood spotting steps.
- Applicable to various fields including prenatal disease and infectious pathology.
Purpose of Study
- To evaluate biomarkers in patients from diverse backgrounds.
- To facilitate the diagnosis of diseases like cancer and infectious diseases.
- To improve accessibility to high-quality samples for research.
Methods Used
- Storage of peripheral blood and serum/plasma samples.
- Evaluation of samples using qPCR and ELISA.
- Comparison of biomarkers between different case series.
- Visual demonstration of blood spotting techniques.
Main Results
- Samples can be stored for at least two weeks without freezing.
- High-quality material is obtained for downstream analysis.
- The method is effective for studying various diseases.
Conclusions
- This technique enhances the ability to study biomarkers in diverse populations.
- It has significant implications for disease diagnosis and research.
- Visual aids are essential for mastering the technique.
Frequently Asked Questions
What is the main advantage of this method?
The main advantage is the ability to store blood and serum samples for at least two weeks without freezing.
How does this method impact translational research?
It allows researchers to study biomarkers in patients from developing countries where frozen samples may not be available.
What types of analyses can be performed with the stored samples?
Downstream analyses such as qPCR and ELISA can be performed on the stored samples.
Why is visual demonstration important?
Visual demonstration is critical because the blood spotting steps can be difficult to learn.
In what fields can this method be applied?
This method can be applied in diagnostic fields such as prenatal diseases and infectious pathology.
What diseases can benefit from this technique?
Diseases such as cancer and infectious diseases can benefit from this technique.
Executive Industry Relevance
Dried blood and serum spot (DBS/DSS) storage addresses a critical bottleneck in biomarker discovery: the need for stable, transportable samples in resource-limited settings. By enabling room-temperature preservation for up to two weeks without compromising downstream qPCR or ELISA performance, this method supports decentralized sample collection and global biomarker validation efforts. It enhances predictive confidence in early discovery by reducing pre-analytical variability associated with cold-chain dependencies.
Strategic Applications in Biopharma R&D
Early Discovery & Target Validation
- Scientific Value: Enables interrogation of therapeutic hypotheses in diverse patient populations where frozen sample infrastructure is unavailable.
- Operational Value: Supports consistent sample handling from collection to analysis, reducing pre-analytical variance in biomarker measurement.
Screening & Assay Development
- Scientific Value: Provides reproducible biological matrices for assay standardization, demonstrated by low coefficient of variation (CV) in ELISA readouts (mean CV 9.6%).
- Operational Value: Facilitates high-throughput screening readiness by eliminating freeze-thaw cycles and enabling batch processing of eluted samples.
Translational & Preclinical Research
- Scientific Value: Maintains biomarker integrity for proteins and nucleic acids, supporting continuity from discovery through preclinical validation.
- Operational Value: Allows longitudinal sampling in field studies, improving risk-adjusted advancement decisions in early development.
Pipeline & Workflow Integration
DBS/DSS functions as a pre-analytical module that integrates into the discovery workflow upstream of molecular and protein assays, enabling sample acquisition in non-traditional environments before proceeding to lead identification and mechanistic studies.
- Discovery Biology: Supports hypothesis testing by enabling biomarker measurement in geographically diverse cohorts, reducing selection bias in target validation.
- Screening: Ensures assay readiness through standardized elution protocols that yield quantifiable outputs compatible with qPCR and ELISA platforms.
- Analytics: Generates measurable dependent variables (e.g., SNP allele frequencies, protein concentrations) that allow statistical comparison across conditions.
- Translational Research: Connects early discovery to preclinical continuity by preserving analyte stability for downstream validation in disease-relevant systems.
- Enterprise Reuse: Represents a scalable, low-infrastructure capability for biobanking and multi-site collaboration, reducing dependency on centralized cold storage.
Operational & Enterprise Impact
- Scientific Value: Increases predictive confidence in biomarker assays by minimizing pre-analytical degradation and ensuring sample comparability.
- Operational Value: Enhances reproducibility and scalability of sample processing across sites, particularly in decentralized or low-resource laboratories.
- Strategic Value: Improves capital efficiency by reducing reliance on ultra-low temperature storage and cold-chain logistics.
- Portfolio Impact: Enables risk-adjusted prioritization of targets through access to broader, more representative sample sets for validation.
Implementation Considerations
- Requires training in proper spotting technique to ensure homogeneous sample distribution and avoid analyte localization artifacts.
- Depends on access to elution buffers and downstream kits compatible with filter paper matrices (e.g., DNA extraction reagents, PBS for protein recovery).
- Necessitates standardization of drying time, humidity control, and desiccant use to maintain spot integrity during storage.
- Requires validation of elution efficiency for specific analytes, as recovery rates may vary between nucleic acids and proteins.
- Limited to analytes stable in dried state; not suitable for labile metabolites or phosphorylated proteins without stabilization.
Biopharma FAQs
Why does sample storage stability matter for target validation?
Stable storage prevents pre-analytical degradation of biomarkers, ensuring that measured changes reflect true biological variation rather than artifacts from improper handling. This is critical for validating therapeutic targets across diverse patient cohorts where cold-chain logistics are unreliable.
How does isolating the independent variable (storage method) improve discovery pipeline reliability?
By standardizing sample preservation via DBS/DSS, researchers isolate storage as a controlled variable, reducing noise in biomarker measurements across sites. This increases confidence that observed differences are due to biological or experimental factors, not sample degradation.
What quantitative dependent variable measurements does this method enable?
The method enables quantification of DNA for SNP analysis via qPCR and protein concentrations for ELISA-based assays, providing measurable outputs for statistical comparison. These data support dose-response modeling and biomarker threshold setting in early discovery.
Why are replication requirements important for cross-functional collaboration?
Replication across multiple spots and samples ensures assay reproducibility, which is essential when transferring methods between laboratories or integrating data from multi-site studies. Consistent CV values (e.g., mean 9.6%) build trust in data sharing and joint decision-making.
What statistical analysis capabilities are required before implementing DBS/DSS in a workflow?
Implementation requires baseline assessment of analyte recovery and variability, including calculation of coefficients of variation between matched fresh and dried samples. Teams must establish acceptable CV thresholds and perform power analysis to ensure sufficient sensitivity for detecting biologically relevant changes.
Chapters in this video
0:04
Title
1:20
Blood Storage in Dried Blood Spots (DBS)
2:20
DNA Extraction Starting from DBS
4:51
Serum Storage for Dried Serum Spots (DSS)
6:02
ELISA Assay Starting from DSS
6:47
Results: Successful Storage of High Quality Blood and Serum at Room Temperature
7:38
Conclusion
