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Following liver injury, hepatic stellate cells (HSC) undergo proliferation and migrate into damaged areas in response to chemotactic factors. HSC have been shown to regulate leukocyte trafficking by secreting monocyte chemotactic protein-1 (MCP-1), a chemokine that recruits monocytes and lymphocytes. In this study, we explored whether MCP-1 exerts biological actions on HSC. HSC were isolated from normal human livers, cultured on plastic, and studied in their myofibroblast-like phenotype, and three different cells lines were used. Chemotaxis was measured in modified Boyden chambers. The tissue response to injury involves the coordinated recruitment and activation of a number of cells in the attempt to repair the damage provoked by toxic, infectious, or immunological mechanisms. Inflammatory cells recruited at sites of damage are responsible for the scavenging of the necrotic cells, whereas myofibroblasts secrete extracellular matrix components and restore the integrity of the tissue. Within the liver, hepatic stellate cells (HSC) are responsible for this second part of the wound-healing response. 1,2 In normal liver, HSC fulfill the role of retinoid storage and metabolism, and their phenotype is referred to as quiescent. However, following injury, HSC undergo differentiation toward an activated phenotype characterized by proliferation and increased secretion of extracellular matrix components. This process is associated with enhanced or de novo expression of receptors for several soluble mediators, such as platelet-derived growth factor (PDGF), transforming growth factor-␤, or thrombin, which mediate the increase in cell proliferation and extracellular matrix production. [3][4][5] Therefore, HSC are the main cell type involved in the deposition of matrix that leads to fibrosis and cirrhosis. Another feature of cells involved in tissue repair is their ability to migrate into the damaged areas according to concentration gradients of chemotactic factors. 6 We have recently shown that HSC share this ability to respond to chemotactic factors such as PDGF. 7 Recent investigation has pointed out additional characteristics of the HSC that are relevant for the hepatic wound healing response. 2 HSC have been shown to express several molecules that are capable of regulating leukocyte trafficking, including chemokines. [8][9][10][11][12] These latter are a group of cytokines that exhibit chemoattractant properties for relatively specific groups of leukocytes. Four classes of chemokines have been recognized according to the position of conserved cysteine residues and differences in the spectrum of target cells. 13 The group of CXC chemokines includes a variety of factors, such as interleukin-8, which are mainly, but not exclusively, chemotactic for neutrophils. 13 Lymphotactin, a cytokine that specifically attracts lymphocytes, is the only known member of the C class of chemokines. 13 A novel cell-associated chemokine characterized by a CX3C motif and higher molecular weight has been recently identified. 14 Chemokines of the ...

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Late hepatic artery thrombosis (HAT) is a rare complication after orthotopic liver transplantation (OLT), conventionally described as occurring more than 30 days after surgery. Only a few reports document its course. In a consecutive series of 634 OLTs (704 grafts), 11 patients (1.7%) had late HAT, diagnosed a median of 6 months (range, 1.8 to 79 months) after OLT. Clinical variables were compared with those of 415 patients without HAT who had a complete database and follow-up, including cytomegalovirus (CMV) surveillance. At presentation, 11 patients had fever, 4 patients had jaundice. Hepatic abscesses were present in 6 patients (3 patients with biliary leak), 4 patients had biliary tree necrosis (2 patients with biliary leak), and 1 patient had no biliary complications. Five patients (45%) underwent accessory hepatic artery anastomosis versus 73 patients (17%) without HAT (P < .05). Five patients (45%) with late HAT had CMV infection versus 14% without HAT (P < .05). Two episodes of late HAT (11 and 79 months) occurred in patients who underwent re-OLT for early HAT (3.9%). Re-OLT was performed in 8 patients a median of 11 days (range, 3 to 37 days) after diagnosis (preceded by intravenous antibiotics and percutaneous drainage). The other 3 patients underwent partial hepatectomy (1 patient), external percutaneous drainage as unfit for surgery (1 patient), and antibiotic therapy only (1 patient). Death occurred in 4 patients who underwent re-OLT (50%) because of septicemia at 11, 23, and 60 days after re-OLT and 17 days after a third OLT. There was one late death (30 months) after partial hepatectomy (hepatitis C recurrence) and one death 6 months after long-term biliary drainage because of sepsis. The 5 survivors have good health with normal liver function test results at a median 52 months (range, 6 to 57 months). In conclusion, late HAT presents with fever caused by hepatic abscesses or biliary leak associated with biliary ischemia and necrosis. CMV infection and accessory hepatic artery anastomosis are risk factors for late HAT in our cohort. Early intervention followed by re-OLT can salvage patients. (Liver Transpl 2003;9: 605-611.) H epatic artery thrombosis (HAT) after orthotopic liver transplantation (OLT) is a potentially lifethreatening complication that occurs in 1.6% to 10.5% of adult liver transplant recipients and 10% to 25% of pediatric cadaver recipients. 1-3 HAT carries a mortality rate of 27% to 58%. 1,4,5 When re-OLT is not performed, the mortality rate increases to 73%. 5 HAT occurring early after OLT is associated with acute fulminant hepatic failure, biliary tract necrosis and leaks, or relapsing bacteremia and results in a high rate of graft loss and patient mortality. Late HAT generally is associated with a milder clinical course than acute HAT. [6][7][8] The time that divides early and late HAT has not been agreed on. Because technical aspects and surgical complications are associated with HAT development in the first 30 days after OLT, it is common practice to use 1 month from OLT to d...