Dynamics of circulating microparticles in liver transplant patients

Background & Aims. Microparticles are small membrane vesicles released from the cell plasma membrane, particularly in cell stress, apoptosis and altered cellular viability. Hepatocellular carcinoma (HCC) is a hypervascular neoplasm with high levels of apoptosis and necrosis. We investigated the levels of circulating microparticles of both tumor and endothelial origins in liver transplant patients with hepatitis C (HepC) cirrhosis with and without HCC and compared them with healthy people and patients with partial hepatectomy. Methods. Using immunolabeling of microparticles of different origin and flow cytometry-based enumeration of microparticles, the levels of circulating microparticles were studied in 8 patients with HepC and 8 patients with both HepC and HCC before and within two weeks after the transplant. Results. The initial levels of circulating microparticles were increased in patients with HepC and HCC as compared to patients with HepC alone. They were also increased in liver transplant patients as compared to patients with partial hepatectomy or healthy people. Levels of circulating microparticles were dynamically changing after the transplant, showing an initial increase with a subsequent decrease by the end of the second week after surgery. In some patients with a complicated clinical outcome, the levels of microparticles were continuously increasing after the surgery. Conclusion. The levels of circulating microparticles of endothelial and hepatic origin in liver transplant patients dynamically change after surgery and correlate with the clinical outcome. Perspectively, the levels of circulating microparticles may be used in clinical practice as a marker of the functional status of the transplanted liver.