Engineered mesenchymal stromal cells with bispecific polyvalent peptides suppress excessive neutrophil infiltration and boost therapy

Excessive neutrophil infiltration can exacerbate inflammation and tissue damage, contributing to conditions like autoimmune disorders and liver diseases. Mesenchymal stromal cells (MSCs) share homing mechanisms with neutrophils, showing promise for treating such diseases. However, ex vivo expanded MSCs often suffer from reduced homing efficiency due to the loss of essential ligands. Here, we engineer MSCs with P-selectin and E-selectin targeting peptides, assembling them into bispecific polyvalent structures using DNA self-assembly technology. This modification allows engineered MSCs to compete with chemotactic neutrophils for selectin binding sites on endothelial cells. In a mouse model of acute liver failure, engineered MSCs effectively home to the damaged liver and significantly inhibit excessive neutrophil infiltration. The combination of inhibiting neutrophil infiltration and the MSCs’ inherent therapeutic properties lead to superior therapeutic outcomes. Single cell RNA sequencing reveals that engineered MSCs elevate the levels of Marco_macrophage which possess neutrophil-inhibitory effects. Our study offers a perspective for advancing MSC-based therapies in tissue repair. 6 hours after injection of 500 mg/kg APAP, mice were then injected with PBS, native MSCs, or engineered MSCs (n=1 for each group). After 4 days, the liver samples were collected, digested, and subjected to scRNA-seq.