Human-Based Immune Responsive In Vitro Infection Models for Validation of Novel TLR4 Antagonists Identified by Computational Discovery

Abstract

Infectious diseases are still a major problem worldwide. This includes microbial infections, with a constant increase in resistance to the current anti-infectives employed. Toll-like receptors (TLRs) perform a fundamental role in pathogen recognition and activation of the innate immune response. Promising new approaches to combat infections and inflammatory diseases involve modulation of the host immune system via TLR4. TLR4 and its co-receptors MD2 and CD14 are required for immune response to fungal and bacterial infection by recognition of microbial cell wall components, making it a prime target for drug development. To evaluate the efficacy of anti-infective compounds early on, we have developed a series of human-based immune responsive infection models, including immune responsive 3D-skin infection models for modeling fungal infections. By using computational methods: pharmacophore modeling and molecular docking, we identified a set of 46 potential modulators of TLR4, which were screened in several tests systems of increasing complexity, including immune responsive 3D-skin infection models. We could show a strong suppression of cytokine and chemokine response induced by lipopolysacharide (LPS) and Candida albicans for individual compounds. The development of human-based immune responsive assays provides a more accurate and reliable basis for development of new anti-inflammatory or immune-modulating drugs.

Activity Models of Key GPCR Families in the Central Nervous System: A Tool for Many Purposes

“…Most GPCR structures still need to be elucidated because detailed structure information requires large-scale expression and purification due to their highly dynamic nature. , Structures are currently reported for ∼120 members of class A GPCRs . This gap may be partially filled by computational modeling − and by improvements in the quality of cryo-EM of GPCR structures . On the other hand, much data about ligand binding and action has been accumulated, including GPCR activation and blocking of GPCR activity.…”

“…Our ISE is a unique and unprecedented generic classification algorithm for finding reasonable solutions to highly complex combinatorial problems . For drug classifications, ,− a learning set comprises molecules known to have an activity (i.e., agonists, antagonists, or inhibitors) on a specific target, diluted by a considerable number (100- or 1000-fold) of assumed inactive molecules. The algorithm randomly picks five property filters out of ∼200 physicochemical properties of each molecule to distinguish between the active (“positive”) and the inactive compounds.…”

Small, Cationic Antifungal Proteins from Filamentous Fungi Inhibit Candida albicans Growth in 3D Skin Infection Models

“…These models can be purchased commercially and represent a feasible alternative to animal testing for pathophysiological studies and pharmacological investigations ( 36 , 37 ). Some publications reported on the use of human 3D FT models to study the fungal infection of the skin and test new antifungal compounds ( 38 – 40 ).…”