Platelets as participants in hyperacute guinea pig-to-rat lung xenorejection

It is well known that xenotransplantation leads to immediate graft dysfunction. This study was designed to specifically examine the role of platelets in mediating lung hyperacute xenorejection (HXR) in a guinea pig-to-rat model. A total of 18 lungs were perfused with blood using an ex vivo apparatus. The animals were divided into the following four groups: a CE group comprising circuit only with rat blood; a SYN group comprising rat lungs and blood; a XE group comprising guinea pig lungs and rat blood; and an SH group comprising guinea pig lungs and rat blood with sarpogrelate hydrochloride, a suppresser of platelet aggregation. The platelet and serotonin in the blood were lower and the wet/dry weight ratio of the lung (W/D) in the XE group were higher than those in the SYN group after perfusion. The platelet count was higher, but the serotonin and W/D were lower in the SH group than in the XE group. These results suggest that platelets strongly affect HXR. Thus, the administration of drugs to suppress platelet aggregation would reduce xenotransplanted lung edema. This paper was presented at the 13th Biennial Asian Congress on Thoracic and Cardiovascular Surgery, held in Sydney, Australia, October 12–15, 1997