Engineering Trispecific IL-2 Receptor Agonistic Antibodies Through Geometry Optimization for Enhanced Treg Targeting

Regulatory T cells (Tregs) are central to maintaining immune tolerance, and their selective activation via interleukin-2 (IL-2) signaling presents a promising therapeutic strategy for autoimmune diseases and transplant rejection. This research addresses the challenge of achieving specific Treg targeting while minimizing off-target effects on conventional T cells and natural killer cells.

The study employed trispecific antibodies designed to simultaneously engage all three IL-2 receptor subunits. By incorporating a second CD25-targeting VHH domain, the researchers aimed to enhance specificity and potency for CD25+ Tregs. Extensive engineering of antibody geometry was conducted to maximize Treg selectivity through optimized spatial configuration.

The main findings demonstrate that this trispecific IL-2R-targeting antibody successfully activates and expands Tregs while sparing other cell types. The platform offers a differentiated approach for immunomodulation, potentially providing new options for treating autoimmune conditions and preventing transplant rejection through selective Treg activation.

This work highlights the importance of spatial configuration in receptor engagement and expands the potential of antibody-based immunomodulation strategies. However, further research is needed to fully characterize the clinical implications and long-term safety profiles of these engineered antibodies before therapeutic application.