Influence of inflammatory cells on early-stage reperfusion injury of canine lung allograft / 第二军医大学学报

ABSTRACT

Objective: To investigate the roles of donor alveolar macrophages and the recipient circulating neutrophils in early-stage reperfusion injury of lung allograft, and to study the interaction between the 2 kinds of cells. Methods: Twenty pairs of size- and weight-matched adult mongrel dogs were randomly assigned to 4 groups C (control), D (leukocyte-depleted blood reperfusion), M (macrophage inhibition) and DM (leukocyte-depleted plus macrophage inhibition). The 20 cases of left lung transplantations were performed by the same surgeon. All procedures were identical, except that the donors in Group M and DM received the macrophage inhibitor gadolinium chloride (14 mg/kg) intravenously 24 h before operation, and that the recipients in Group D and DM underwent initial 10 rain reperfusion with leukocyte-depleted blood collected from donors' inferior vena cava. All lung allografts were reperfused for 2 h. Results: Compared with Group D and C, macrophage inhibition ameliorated PO2/FiO2 and mean pulmonary arterial pressure (mPAP) consistently after 30 rain reperfusion in Group M and DM; the parameters of lung reperfusion injury (malonaldehyde activity, wet/dry ratio) at 120 min after reperfusion were also significantly improved (P<0.05). Initial leukocyte-depleted reperfusion had no remarkable influence on allograft reperfusion injury, although it reduced pulmonary leukostasis (myeloperoxidase activity) significantly at 120 min after reperfusion. There were no significant interactions between leukocyte-depletion and macrophage inhibition in oxygenation, mPAP, wet/ dry ratio, malonaldehyde and myeloperoxidase activity. Conclusion: It is the donor alveolar macrophages, not the recipient circulating neutrophils that can aggravate the inflammatory cascade in lung allografts during 2 h after reperfusion and no interaction is detected between them.