High Throughput Screening


Johana Tournois: Platform Manager engineer (CECS)

Raif Eren Ayata: Platform engineer (CECS)

Alexandre Carteron : Platform technician (CECS)

plateforme HTS

Aims and background:

The High Throughput Screening (HTS) activity is part of the drug discovery process, and consists in selecting among thousands of molecules the ones that could have a pharmaceutical use. To do that, large compounds libraries are tested on a biological model showing a specific therapeutic target. The HTS at I-Stem focuses on relevant biological models of genetic diseases: the human stem cells and their progenies. The self-renewable capacity of these cells, their ability to differentiate into several tissue progenitors (neural, myoblast, mesenchymal stem cells…), and the possibility to work with mutated cell lines define human stem cells as a good basis for screening compounds libraries in order to discover new potential drugs for monogenic diseases.

Once a disease has been explored with genomic, proteomic and cell biology tools, relevant targets are identified by I-Stem research teams. Then, the first objective of the HTS platform, in collaboration with the scientific team is to develop a robust cell based assay in microplates (96- 384- wells) with a specific read out. When the assay has been set up, the custom I-Stem compounds libraries are tested during the primary screening campaign. The screening is then followed by the retest, counter-test and EC/IC50 evaluation steps. Finally, the lead optimization is done in collaboration with our chemist partners.

To be able to develop reproducible and reliable tests in sterile conditions, the HTS platform was set up with robots, readers, and a good data mining system.


Strategy, means and methods:

In addition to carrying out screening after the test has been developed in collaboration with the scientific team in charge of the project, the platform conducts R&D programs such as the creation of a evolving database to optimize the use of its customized chemical libraries and also the implementation of new tests according to the laboratory’s needs

POSTER : Seeking a novel foundation for a repurposing strategy to treat ultra-rare diseases


The HTS platform is equipped with several robotic systems:

  • The Bravo-Benchcel (Agilent) is a compact pippeting station connected to a plate storage system. This platform treats 5 to 20 plates and is mainly used for the assay development step, cherry picking and serial dilution protocols
  • The Biocel 1800 (Agilent) allows to handle in sterile conditions nearly 200 plates (96- 384- wells plates) for compound management tasks and primary screenings
  • An automated cell fixation and staining platform (Thermo, Biotek) is used for High Content Screening campaigns (HCS)
  • One HTS reader is available: the Clariostar (BMG Labtech) is a multimode detection system (luminescence, fluorescence, TR-FRET, Alphascreen, Alphalisa, HTRF…)
  • Two HCS readers are available: The Arrayscan (Cellomics) and the Image Express (Molecular device) are automated fluorescence microscope. From the cell imaging platform .https://www.istem.eu/en/technological-platforms/cell-imaging/


Our platform is equipped with a powerful Laboratory Information Management System (LIMS) allowing the management of chemical libraries but also the analysis of screening.


Results and future prospects:

Recently several screening campaigns were performed on the HTS platform:

  • Two drug screenings on Limb-Girdle Muscular Dystrophy (LGMD) (Articles in progress)


  • Two drug screenings on Hutchinson Gilford progeria pluripotent stem cells:

First to the identification of inhibitors of prelamin A farnesylation. (Article Link)

Second to the identification of compounds that counteract premature osteogenic differentiation.(Article Link)


  • High throughput screening for inhibitors of REST in neural derivatives of human embryonic stem cells reveals a chemical compound that promotes expression of neuronal genes (Article Link)

A collaboration with the Roche pharmaceutical company led to the screening of 200 000 Roche compounds on human neural stem cells in order to identify proliferative drugs.



Discngine, Paris, France (database management systems (SAW) and Multi-parameter visualization tools (Spotfire))

Pierre Fabre (Nature Open library)