Expression of stress proteins, adhesion molecules, and interleukin-8 in endothelial cells after preservation and reoxygenation

Endothelial activation is a central feature of preservation-induced allograft injury. The present study aims at a quantitative assessment of stress proteins, adhesion molecules, and interleukin-8 in a cell culture-based model of organ preservation. Human umbilical vein endothelial cells were exposed to cold, hypoxic storage in University of Wisconsin (UW), histidine-tryptophane-ketoglutarate (HTK), and EuroCollins solutions for 8 h with subsequent rewarming/reoxygenation (rew/reox) for 1 and 4 h. A cell-based ELISA was designed for detection of heat shock proteins (HSP) 60 and 70, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), and endothelial leukocyte adhesion molecule-1 (ELAM-1). Immunohistochemical staining was performed for comparison. Interleukin-8 was quantified by ELISA. HSP 70 was expressed after cold storage in HTK and EuroCollins solution and after rew/reox in all groups. A constitutive expression of HSP 60 was observed with further upregulation after rew/reox following cold storage in all experimental groups. ICAM-1 was clearly upregulated, but VCAM-1 showed only weak expression after cold storage and rew/reox. ELAM-1 was detectable in minimal amounts after cold storage but was considerably upregulated after 4 h of rew/reox. A significant increase of interleukin-8 release could be found after 4 h of rew/reox following storage in EuroCollins solution. Expression of stress proteins can be considered as a new parameter of preservation-associated endothelial activation. Apart from possible protective effects, allograft vasculopathy could be in part a consequence of the antigeneic potential of heat shock proteins connected with effects caused by adhesion molecules and inflammatory cytokines.