Inhibiting Integrin αvβ5 Reduces Ischemia-Reperfusion Injury in an Orthotopic Lung Transplant Model in Mice

Area of Science:

• Transplantation immunology
• Vascular biology
• Integrin signaling

Background:

• Primary graft dysfunction (PGD) is a major complication after lung transplantation, leading to significant morbidity and mortality.
• PGD involves disruption of endothelial and epithelial barriers, causing lung edema and impaired gas exchange.
• Integrins, like αvβ5, are crucial for maintaining cell barrier integrity and have been implicated in lung injury models.

Purpose of the Study:

• To investigate the potential of inhibiting αvβ5 integrin during donor lung cold ischemia to mitigate ischemia-reperfusion injury.
• To determine if αvβ5 blockade can reduce endothelial permeability and prevent primary graft dysfunction in a lung transplantation model.

Main Methods:

• An orthotopic single lung transplantation model was utilized, comparing lungs subjected to prolonged cold ischemia (18 hours) versus those without.
• Donor lungs were perfused with an αvβ5-blocking antibody (ALULA) or a control antibody during the collection phase.
• Lung injury parameters, including extravascular lung water, protein permeability, neutrophilic alveolitis, and oxygenation, were assessed after 8 hours of reperfusion.

Main Results:

• Prolonged cold ischemia significantly increased lung injury markers and decreased oxygenation.
• Perfusion with the αvβ5 antibody effectively protected donor lungs from ischemia-reperfusion injury compared to the control antibody.
• Treatment with the αvβ5 antibody led to significantly improved oxygenation post-transplantation.

Conclusions:

• αvβ5 integrin blockade during cold ischemia is a promising strategy to protect donor lungs from ischemia-reperfusion injury.
• This approach demonstrates potential for preventing primary graft dysfunction in clinical lung transplantation.
• Targeting αvβ5 integrins offers a novel therapeutic avenue for improving lung transplant outcomes.