Biomarker Discovery Solutions: RayBiotech’s Guide & Overview

The discovery of good biomarkers and their translation to the clinic is a challenging and multistep process, for which RayBiotech can provide expertise and a variety of tools to build a tailored solution.

The great challenge of biomarker discovery (and its relatively low success rate) is partly attributable to lack of a well-established validation method for candidate biomarkers identified in the initial screen. Using traditional proteomics methods, it can be difficult to follow up on positive hits if no probes are available. This difficulty can be addressed by the utilization of affinity proteomics, in which a pre-qualified antibody pool is applied to both the discovery (screening) process and the downstream stages of verification and validation. Herein lies the core strategy of RayBiotech’s biomarker discovery platform: high-content antibody arrays to tackle protein biomarker candidate discovery, followed by customizable quantitative immunoassays (multiplex or singleplex) to carry out validation studies.

Translation to the clinic often culminates in the development of an ELISA-based or lateral flow test. Since each of the aforementioned methods can share common antibodies, the development and optimization of downstream immunoassays is greatly streamlined. Thus, antibody arrays serve as versatile tools to help bridge the gap from discovery to validation with ease.

Experimental Design

This often underappreciated step is foundational to successful biomarker discovery and validation.

The first important consideration is n. Sample numbers for each experimental group must be large enough to ensure statistical significance. If the sample size is too low, more biomarker candidates may be unfruitful in the validation phase (false positives) or some useful biomarker candidates may be missed (false negatives). The minimal n per group largely depends on the objectives of your experiment, but our Biostatistics and Bioinformatics Group can assist you in making this determination.

Secondly, the researcher must consider if the proposed assay is suitable for the intended study. Rather than a single one-size-fits-all platform, RayBiotech’s uniquely diverse offering includes a wide range of multiplex protein detection products to fit different purposes. These include high-density (>200 targets) antibody arrays (quantitative or semi-quantitative) for screening protein expression, smaller focused array panels for querying specific cellular functions, phospho-specific arrays for pathway profiling, protein arrays for exploring protein-protein and protein-small molecule interactions, and glycobiology-focused arrays for collecting glycosylation signatures. For difficult-to-detect targets, we offer ultrasensitive ELISA technologies including immuno-PCR ELISA and SIMOA. Our Technical Support team can assist you in choosing the best platform and product for your needs.

In addition to choosing an appropriate array, consideration of experimental methods is also an important aspect of biomarker development. This includes careful definition of patient populations (or animals in the case of experimental model systems), choosing an appropriate sample type, and standardized sample handling and storage protocols - all of which can make the difference between success and failure in biomarker development studies. While our Technical Support personnel and scientists cannot be experts in every field of study, we can assist you in reviewing experimental methods for optimal use with antibody array products.

RayBiotech also offers a bio-banking service for customers with sample storage space needs.

Biomarker Candidate Screening

RayBiotech has developed an innovative platform for biomarker discovery and validation.

Researchers can choose from several different array platforms to initiate biomarker development, utilizing them either alone or as a supplement to mass spectrometry-based proteomics. RayBiotech’s highest-density arrays contain hundreds to thousands of antibodies, providing a wide, diverse pool of disease-specific proteins from which to identify candidates for further investigation. Alternatively, the screen can begin with smaller panels of 40 to a few hundred antibodies, focusing on specific subsets of markers (e.g. growth factors, apoptosis markers, or phosphorylated kinases).

For an overview and comparison of antibody arrays (affinity proteomics) and mass spectrometry (traditional proteomics), click here.

Biomarker Candidate Validation

Developing probes for validation of candidate biomarkers is resource-intensive, costly, and can impede the progress of discovery. However, using RayBiotech’s high-density array platform for candidate screening takes that difficulty out of the equation, since the array panel contains reliable, validated antibodies to every protein of interest. By giving the researcher access to these antibodies and ready-made immunoassays that contain them (ELISAs and small targeted arrays), downstream verification and validation experiments can be carried out efficiently. Thus, our platform streamlines the workflow for biomarker development, making it faster and more affordable.

Translation to Clinical Applications

While RayBiotech’s reagents and immunoassays are initially validated for research use only, we are an ISO 13485:2016 certified company (the certification required for the manufacture of clinical diagnostic products). As such, RayBiotech products can be used in clinical diagnostic lab developed tests. In addition, RayBiotech is fully willing and able to aid in the validation of one or more of our immunoassays or array platforms for FDA clearance for use as a Clinical Diagnostic product for sales. RayBiotech can offer its technical expertise as well as assistance in preparing and submitting data for clinical assay approval.

Custom Array Development

In addition to offering off-the-shelf antibody and protein arrays, RayBiotech can produce customized arrays to fit your needs for biomarker screening or validation.

Sandwich-based Arrays

• Choose from over 3500 validated antibody pairs across 13 species
• Assemble your own semi-quantitative or quantitative panels in nearly any combination (after an antibody cross-reactivity check by the technical service team).
• Custom sandwich-based array

Label-Based Arrays

• Direct-labeling method eliminates need for antibody pairs
• Offers even greater flexibility for antibody combinations (no cross-reactivity check needed)
• Short development time for customization (a few weeks)
• L-Series array

We can also produce customized protein arrays to probe for protein–protein interactions, interactions of proteins with DNA, RNA or small molecules, auto-antibody production or antibody specificity.

Custom Immunoassay Development

In some cases, the necessary immunoassays for detecting your favorite protein (YFP) may not be available.

RayBiotech’s core competency is immunoassay development. Our scientists are experts at designing, developing and validating multiplex and single-plex immunoassays. If you have a favorite target for which you need a reliable immunoassay, we can help.

If you would like a quote for custom assay development, please contact us.