GALA3-Containing Modular Nanotransporters Are Capable of Delivering Keap1 Monobody to Target Cells and Inhibiting the Formation of Reactive Oxygen Species in the Cells.

In the previously created modular nanotransporter (MNT) capable of delivering a monobody to Keap1 into the cytosol, the endosomolytic module, translocation domain of diphtheria toxin (DTox), was replaced by the endosomolytic peptide GALA3. It was found that this substitution more than doubles the lifetime of MNT in the blood. Using confocal microscopy, it was shown that MNT with GALA3 was internalized into AML12 cells mainly due to binding to the epidermal growth factor receptor, and is also able to exit from endosomes into the cytosol. Using cellular thermal shift assay, it was shown that MNT with GALA3 and MNT with DTox are equally effective in disrupting the formation of the Nrf2 complex with Keap1, which led to similar protection of AML12 cells from the action of hydrogen peroxide. The obtained results allow not only optimizing the systemic use of MNT, but can also serve as a basis for creating agents aimed at treating diseases associated with oxidative stress.