Kindlin-3 is a Regulator of Force-Regulated Activation of Integrin α4β7 by CCL25 During Lymphocyte Adhesion.

PURPOSE: Lymphocyte recruitment to inflamed intestines in inflammatory bowel disease (IBD) critically depends on shearstress-regulated integrin α4β7/MAdCAM-1 interactions. However, the mechano-chemical coupling between the chemokine CCL25 and the intracellular adaptor Kindlin-3 in activating α4β7 under physiological flow remains unclear. METHODS: Utilizing parallel-plate flow chamber assays combined with fluorescence microscopy and molecular perturbation, wedemonstrate that CCL25 triggers robust integrin α4β7 activation and stable lymphocyte adhesion only under physiological shear stress, a process regulated by Kindlin-3. RESULTS: Mechanistically, Kindlin-3 acts as a force transmission hub, enabling CCL25 signaling to enhance α4β7-mediatedadhesion strengthening. Knockdown of Kindlin-3 specifi cally enhanced the force-sensitized, CCL25-induced activationof α4β7. CONCLUSIONS: This study reveals, for the first time, that Kindlin-3 is crucial for translating chemokine (CCL25) signals intobiomechanical activation of integrin α4β7 under shear flow. Our findings establish Kindlin-3 as a critical mechano-regulator of chemokine-induced integrin activation during lymphocyte homing, providing novel mechanistic insightsinto IBD pathogenesis and highlighting this pathway as a promising target for anti-adhesion therapeutics. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at https://doi.org/10.1007/s12195-026-00935-9.