Progression of endothelial activation to endothelial dysfunction leading to different complications associated with HCT. Figure adapted and reprinted by permission from Springer Nature Customer Service Centre GmbH: Springer Nature Bone Marrow Transplantation. 2011;46(12):1495–1502. Carreras, E. & Diaz‐Ricart, M. The role of the endothelium in the short‐term complications of haematopoietic SCT. ©2011. CAR‐T, CAR‐T‐associated neurotoxicity; DAH, diffuse alveolar haemorrhage; EHPF, endothelial hyperpolarizing factor; GvHD, graft‐versus‐host disease; HCT, haematopoietic cell transplantation; ICAM‐1, intercellular adhesion molecule 1; IL1‐β, interleukin 1 beta; IPS, idiopathic pneumonia syndrome; NO, nitric oxide; PA‐1, plasminogen activator inhibitor 1; TA‐TMA, transplant‐associated thrombotic microangiopathy; TF, tissue factor; TM, thrombomodulin; TNF, tumour necrosis factor; t‐PA, tissue plasminogen activator; VCAM‐1, vascular adhesion molecule 1; VOD/SOS, veno‐occlusive disease/sinusoidal obstruction syndrome; vWF, von Willebrand factor.