Transcriptional expression of hypoxia/hypothermia-conditioned human endothelial cells and their interaction with monocytes / 中华器官移植杂志

ABSTRACT

Objective To characterize molecule profiling for hypoxia/hypothermia-conditioned human endothelial cells(EC),and to examine the hypothesis that the interaction between hypoxia/hy- pothermia-conditioned EC and monocytes plays a key role in early hypoxia/hypothermic reperfusion in- jury.Methods Human aortic EC were conditioned in hypoxia/hypothermia chamber at 4℃for 91) rain followed by 4 to 8 h re-warming at 37℃and then analyzed initially by RT-PCR to evaluate RNA transcripts.To examine early cellular interactions,a cellular adhesion study was performed using EC and fluorescence-conjugated DIO labeled purified human monocytes,and CD4~+ T cells as well as PB- MC.Interactions between PKH-26-labeled EC and these cells were carried out to determine EC mem- brane uptake by monocytes.Results RT-PCR analysis demonstrated that hypoxia/hypothermia-con- ditioned EC up-regulated RNA transcripts of inflammatory cytokines,ECE-1 and endothelin,co-stim- ulatory molecules,and adhesion molecules CD54.FACS showed minimal up-regulation of CD54 on hy- poxia-hypothermia-conditioned EC.Low level adhesion of purified CD4~+ T cells to resting and hypoxi- a/hypothermia-conditioned EC was noted.In contrast,high levels of monocyte adhesion to hypoxia/ hypothermia-conditioned EC were observed when compared to resting EC.EC membrane up-take by monocytes but not CD4~+ T cells was revealed by FACS,and the levels of EC membrane up-take were similar to those of the normal EC.Conclusions Hypoxia/hypothermia-conditioned EC demonstrated up-regulation of multiple RNA transcripts associated with inflammatory responses,cellular adhesion and co-stimulation.Human monocyte adhesion to hypoxia/hypothermia-conditioned EC was greater than T cells.Monocytes up-took EC membrane during their interaction.These findings suggest that the initial interaction between monocytes and hypoxia-hypothermia EC,but not T cells,may play a critical role during early reperfusion injury.