Profiling a structure activity relationship library for immunological activity in human PBMCs: multiplexed measurements of cell phenotype, viability, and cytokine secretion from a single high throughput screen (TECH2P.923)

The success of immunomodulatory approaches for the treatment of disease has generated tremendous interest in discovery of new immunotherapy based therapeutics. Immunotherapy has the potential of affecting - positively and negatively - the myriad interactions among cells and signaling molecules regulating the immune system, and projects should include high throughput screening campaigns aimed at profiling the effects of compounds on these complex interactions. We describe a no-wash, high throughput screen that provides a multiparameter activity profile for a structure activity relationship (SAR) library of immunomodulatory compounds. Seven known immunomodulatory compounds were used as templates to generate an SAR expansion library of 1438 compounds. The selection utilized a combination of various substructure and similarity search methods combined with the generation of virtual templates. Phytohemagglutinin (PHA) activated PBMCs were treated with the compounds at two doses, 10µM and 50µM. Immunophenotyping was done by α-CD3 and α-CD8 antibodies and differential toxic effects of compounds on the viability of individual cell subsets plus effects on the secretion of three cytokines were used to generate an immunological profile for each compound tested. We demonstrate the combination of a robust SAR expansion system with high throughput, multiplex screening on primary cells to generate activity profiles that can be used for identifying viable therapeutic candidates.