Modulation of fibronectin extracellular matrix enhances anti-tumor efficacy of immune checkpoint blockade.

ABSTRACT: The success of immune checkpoint inhibitors is limited by multiple factors, including poor T cell infiltration and function within tumors, partly due to a dense extracellular matrix (ECM). Here, we investigate modulating the ECM by targeting integrin α5β1, a major fibronectin-binding and organizing integrin, to improve immunotherapy outcomes. Use of a function-blocking murinized α5β1 antibody reduces fibronectin fibril formation, enhances CD8⁺ T cell transendothelial migration, increases vascular permeability, and decreases vessel-associated collagen. These changes culminate in improving the effectiveness of PD-L1 blockade, alone or with chemotherapy, in the E0771 breast cancer model. Clinically, high integrin alpha 5 (ITGA5) expression correlates with worse survival in patients

SUBMITTER: Khan KA 

PROVIDER: S-EPMC12490255 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature