SUMMARY
MSD is a one stop immunoassay platform with multiplexing and high throughput capabilities that allows fast, accurate and quantitative detection of biological samples at low volume. It could be a time- and cost-effective alternative to the regularly used biomolecule detection technologies in the laboratory.
CONCEPT
Meso Scale discovery (MSD) is an immunoassay-based platform that utilizes high binding carbon electrodes and electro chemiluminescence (ECL) detection that is a more sensitive and versatile alternative to a conventional ELISA. Like ELISAs, MSD can be used in a direct, indirect or sandwich immunoassay. In the MSD platform, biological reagents (antigens or antibodies) are coated on the carbon electrode (10X binding capacity compared to polystyrene plate) at the bottom of a micro titer plate format (Fig. 1). Bound samples are then incubated with a ECL labeled (SULFO-TAG) detection antibody. Following application of an electrical current across the carbon electrode, the SULFO-TAG reacts with the Ru(bpy)32+ reagent and Tripropylamine (TPA) catalyst in the detection buffer and resulting in the emission of light that can be quantitated at 620 nm with a CCD camera.
Figure1: Basic components of MSD depicting the ECL reaction
ADVANTAGES
Sensitivity, Range and Ease-of-Use: In comparison to a conventional ELISA, MSD has higher sensitivity (LLOD 0.1-1.4 pg/mL) and a larger dynamic detection range (0.1-10 pg/mL). In addition, MSD has an efficient low volume sampling (1-25μL) and minimized matrix effect aiding in simultaneous multiplex detection with high precision. Furthermore, MSD has simpler protocols, reduced washing steps and faster read times making it an efficient platform for high throughput sampling.
ELISA |
MSD |
|
Sample Volume Requirement |
50-100 µL (per analyte) |
10-25 µL (up to 10 analytes) |
Multiplex Panels |
No |
10 analytes simultaneously |
Dynamic Range |
1-2 logs |
3-4+ logs |
Matrix Effects |
Yes |
Greatly reduced |
Simple Protocol |
No |
Yes |
Wash Steps |
Many |
Typically 1-3 |
Read Times |
Slow |
Up to 960 results in 1-3 min |
Versatility: Like ELISAs, the carbon electrode of the MSD platform can be coated with a variety of different capture materials (antibodies, proteins, peptides, carbohydrates, polysaccharides and cell lysates) and has been applied in the analysis of clinically proven biomarkers like cytokines, chemokines, etc (biomarker assay); Pharmacokinetic/Toxicokinetic (PK/TK) analysis (biologic testing); human immune response against biologics (anti-drug antibodies (ADA) immunogenicity assays); determine drug efficacy (potency bioassay); determine drug product identity, purity, concentration and stability (identity bioassay) during manufacturing process etc. MSD is also a useful alternative to western-blotting due to its capability to support low sample volume, allows fewer processing steps (simplified workflow) and provide quantitative results faster.
MSD is standardized to analyze a wide range of biological sample types including cell culture supernatant, cell lysates, cell lysates/tissue homogenates, serum/plasma. All of this makes the MSD platform a useful tool for variety of applications of biopharmaceutical industry in various stages of drug discovery, development, manufacturing and for clinical studies.
MSD provides 'ready to use pre-validated' and 'customized to fit for purpose' kits with single analyte (single-plex) or multianalyte (multi-plex) panel configurations, MSD offers assay kits in different format encompassing a broad range of sample matrices from Human, Mouse, Rat and Canine samples: with excellent analytical performance and lot-to-lot consistency.
Multi-plexing: One of the greatest advantages of the MSD platform is the simultaneous multi-plex detection. In both the 96 and 384 well plate formats, up to 10 and four different capture antibodies, respectively, can be bound in distinct spots on the carbon electrode (Fig. 2). This allows the detection of up to 10 distinct analytes within a complex sample in a single well increasing productivity and improving efficiency.
Figure 2. MSD Multi-Spot Plate for Multi-plexing
DISADVANTAGES
MSD plates requires special readers and software which is only available from MSD.
REFERENCES