Design of high-affinity miniprotein antagonist targeting IL-4Ra for IL-4/IL-13 signal blockade

IL-4Ra, a crucial receptor for type 2 inflammatory responses, is targeted by IL-13Ra to activate the JAK1-STAT6 pathway upon binding with IL-4 or IL-13. This receptor is a prime target in the development of therapeutics for allergic diseases, with dupilumab being a notable monoclonal antibody drug that blocks both IL-4 and IL-13, ushering in a new era of precision therapy for type 2 inflammation.

In this study, scientists employed large-scale deep learning-based computational design methods to create mini-protein antagonists that specifically target both human and mouse IL-4Ra. The binding affinity of these new antagonists was enhanced from 22.1 nM to an impressive 569 pM through partial diffusion. To ensure the accuracy and specificity of these designs, researchers verified them using X-ray crystallography and biochemical studies.

The de novo designed monomeric mini-protein antagonists demonstrated comparable blockade ability to the bivalent dupilumab, as confirmed by in vitro IL4/IL13 signal blockade assays. Furthermore, in vivo pharmacokinetic half-life studies showed that fusing the mini-protein antagonist to an HSA-binding domain significantly extended its half-life from 2.7 hours to 60.6 hours.

The mini-protein antagonist also exhibited excellent expression levels, solubility, and thermal stability, with its IL4/IL13 signal blockade ability remaining intact even after being heated to 95 degrees Celsius.

In summary, through the use of large-scale cluster computing and deep learning-based de novo design techniques, the research team successfully developed a well-performing IL-4Ra mini-protein antagonist with promising potential for drug development.