Visualization of Endothelial Cell Structure During Machine Perfusion Preservation of Livers

摘要

The development of machine perfusion preservation (MPP) of kidney has led to significant improvements and greater success rates in kidney transplantation by providing superior preserved tissue and viable non-heart-beating donor tissue. However, machine perfusion of livers has not been successful in improving preservation. Currently, the major cause of damage associated with MPP of livers remains unclear. Previous studies showed increased vascular resistance and blockages during and after 24hrs MPP but no direct evidence existed. Utilizing a novel two colors fluorophores labeling, an intravital microscopic study was conducted to obtain real time images and confocal microscopy to get detailed images in order to correlate fluorescent-tagged endothelial cells (ECs) with red cell stasis. Fluorescein isothiocynate (FITC) was used to label red blood cells (RBCs) and DiI acetylated low-density lipoprotein (DiI acLDL) was used to mark ECs. Structure of ECs was recorded and assessed during 24hrs MPP with University of Wisconsin (UW) solution at 4°C with a flow rate of 4ml/min. Images recorded from intravital microscopy and confocal microscopy show ECs rounding over a period of 24 hrs and subsequent red blood cells stasis after 24hrs MPP and during rewarming.