Mechanosensory channel Piezoi contributes to T lymphocyte migration through direct interaction with integrins

Abstract Response to mechanical signals is an important mechanism by which T lymphocytes drive inflammation. A potential contributor in this process is Piezo1, a mechanosensitive cation channel which is abundantly expressed in T lymphocytes. Previously, our lab has shown that Piezo1 colocalizes with high affinity LFA-1 on activated human T lymphocytes during chemokine-activated crawling, suggesting a role for Piezo1 in the adhesion cascade. However, the mechanism by which Piezo1 contributes to the regulation of the adhesion cascade is unknown. We hypothesize that Piezo1 mediates T lymphocyte migration through direct contact with integrin to regulate its function. We investigate the role of Piezo1 in the expression, binding affinity, and turnover of LFA-1 and VLA-4. Co-immunoprecipitation revealed a preferential association of Piezo1 with the alpha subunit of integrins, specifically LFA-1, MAC-1, and VLA-4 in the active forms. Moreover, microfluidic devices were used to study the contribution of Piezo1 on T lymphocytes under laminar flow-induced shear stress. We found that activated T lymphocytes with CRISPR/Cas9-mediated Piezo1 ablation resulted in a reduced chemokine-induced crawling speed that correlates to the efficiency of Piezo1 gene ablation. Finally, in studies of lymph node homing where fluorescently labeled T lymphocytes were tracked in vivo, Piezo1 deficient cells exhibit increased ingress and decreased egress through the lymph node, suggesting an intricate role of Piezo1 on T lymphocyte migration. Taken together, our data support the hypothesis that Piezo1 modulates inflammatory processes through complex integrin interactions and mediates T lymphocyte migration from the lymph node to the site of inflammation. Case Postbaccalaureate Research Education Program grant NIH/NIGMS 5R25GM075207-15; St. Baldrick’s Foundation; Hyundai Hope-on-Wheels Program; The I’m Not Done Yet Foundation; and Pediatric Cancer Research Foundation