In conjunction with our 30th company anniversary, we invite you all backstage and introduce the people behind our microplate readers.
High-throughput screening (HTS)
Table of contents
People behind our Plate Readers
What is high-throughput screening?
High-throughput screening (HTS) is a drug discovery process that allows automated testing of large numbers of chemical and / or biological compounds for a specific biological target. High-throughput screening methods are extensively used in the pharmaceutical industry, leveraging robotics and automation to Quickly test the biological or biochemical activity of a large number of molecules, usually drugs. They accelerate target analysis, as large scale compound libraries can quickly be screened in a cost effective way. HTS is a useful tool for assessing for instance pharmacological targets, pharmacologically profiling agonists and antagonists for receptors (such as GPCRs) and enzymes.
High-throughput screening in drug discovery
The primary goal of HTS is to identify through compound library screenings, candidates that affect the target in the desired way, so called “hits” or “leads”. This is usually achieved employing liquid handling devices, robotics, plate readers as detectors and dedicated software for instrumentation control and data processing.
Importantly, high-throughput screening processes do not usually identify drugs, as several properties that are critical to the development of a new drug cannot be assessed by compound library screening. For instance HTS cannot evaluate toxicity and bioavailability. The primary role of high-throughput screening assays is instead to identify “leads” and provide suggestions for their optimization. The results of HTS assays provide hence the starting point for further steps in the drug discovery pipeline like drug design, and for understanding the interaction or role of a particular biochemical process .
Consequently, high-throughput screening should be seen as a fast scan of biological processes by which compounds with a poor or no effect can be rapidly excluded from the analysis pipeline.
High-throughput screening services: pharma, CROs and universities
In recent times, HTS was largely enabled by the modern advances in robotics, liquid handling, plate reader detection as well as high-speed computers. Nevertheless, to run effectively, high-throughput screening still requires a highly specialized and expensive screening facility that not every lab can afford. As an alternative to setting up one´s own facility, institutions with limited budgets usually access HTS services provided by third party provides such as Contract Research Organisations (CRO) or, mainly in an academic environment, core facilities. In the below video Becky Allsopp explains which services Sygnature Discovery as a CRO can provide to customers and how the PHERAstar FSX fulfils their needs.
Through its past generations, the PHERAstar FSX has been looked at as the reference reader for the field. The following features make it the gold standard for high-throughput screening:
- Highest sensitivity on the market for fluorescence intensity and polarization
- Measurement in 384-, 1536- as well as 3456-well plate formats
- Simultaneous Dual Emission detection for fast and robust detection of fluorescence polarization assays, BRET, FRET and TR-FRET as well as AlphaScreen ® assays
- Dedicated AlphaScreen ® / AlphaLISA ® excitation laser
- High-frequency TRF laser allows efficient measurement of 1536-well plates on the fly (1 flash) in just 36 seconds
High-throughput screening applications
Although one of the most targeted group of receptors in drug screening are G-Protein Coupled Receptors (GPCRs), not every benchtop assay can be converted to an automated HTS, especially when using living cells. Application Note 287 describes how for the first time NanoBRET was successfully used to monitor ligand-GPCRs binding in living cells.
NanoBRET assay for monitoring of ligand binding to GPCRs in live cells
Read how the CLARIOstar and the PHERAstar were used for this assay.
An important issue in HTS is miniaturisation. Samples have to be as small as possible in order to save costs, but still deliver reliable results. The sensitivity of the microplate reader and its ability to reliably measure samples in high-density plate formats is consequently of great importance. In Application Note 229 , DiscovereX PathHunter reporter cell lines were measured with the PHERAstar FS in both 1536- and 3456-well plates. The reader was able to detect signal coming from as few as 1,000 cells in a 1,536- and 250 cells in a 3,456-well plate. Similarly, Application Note 260 shows how an AlphaLISA assay was miniaturized down to 2 µL per sample in a 1536-well plate and detected on the PHERAstar FS .
In drug screening, speed is as important as miniaturization. Application Note 295 shows how the PHERAstar FSX equipped with the TRF excitation laser, is able to detect HTRF ® assays in 1536-well plates “on the fly” in only 36 seconds, still delivering a Z` value> 0.8.
Cellular and biochemical HTRF assays measured in 1536-well microplates
PHERAstar FSX offers robust and fast reading for HTS and compound follow-up
Customer success story
Searching for novel kinase inhibitors with the PHERAstar FSX plate reader at BIENTA laboratory in Kyiv, Ukraine. The HTS group screened more than 600,000 compounds in kinase assays using ATP depletion assay, measuring luminescence in a coupled luciferase reaction.
PHERAstar plate readers are routinely used in the laboratory as they provide an accurate signal, high throughput and sensitivity, as well as stable temperature control required for luminescent kinase assays.