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Veno-occlusive disease/sinusoidal obstruction syndrome (VOD/SOS) occurring after liver transplantation is a relatively rare complication but it often takes a life-threatening course. However, the detailed etiology and mechanism of VOD/SOS after liver transplantation (LT) remains unclear. We report two cases with rapidly progressive VOD/SOS after ABO-identical LT resistant to various therapies. In case 1, in which the patient underwent deceased-donor LT, the first episode of acute allograft rejection was triggered VOD/SOS, and the presence of donor non-specific anti-HLA antibodies was confirmed. The recipient died with graft failure on day 46 after transplantation. Case 2, in which the patient underwent living-donor LT from the mother, had neither rejection nor mechanical venous obstruction, but condition of the patient rapidly worsened and he died on day 13 after transplantation. This recipient's direct cross-match test for the donor's B lymphocyte was strongly positive, but that for T lymphocyte was negative. In both cases, neither stenosis of hepatic vein outflow tract nor C4d deposition in post-transplantation liver biopsy specimens and autopsy specimen was found. On the other hand, in both cases, the patient was transfusion unresponsive thrombocytopenia and hyperbilirubinemia persisted postoperatively, and glycoprotein Ⅰ bα was strongly stained in the neighboring centrilobular area (zone 3), especially in the space of Disse, and platelet phagocytosis was observed in Kupffer cells and hepatocytes around zone 3 such as clinical xenotransplantation of the liver in post-transplantation liver biopsy specimens. From the viewpoint of graft injury, VOD/SOS was considered that sustained sinusoidal endothelial cells injury resulted in bleeding in the space of Disse and led to around centrilobular hemorrhagic necrosis, and the fundamental cause was damage around centrilobular area including sinusoid by acute cellular rejection, antibody-mediated rejection or ischemic reperfusion injury. The extrasinusoidal platelet activation, aggregation, and phagocytosis of platelets were some of the main reasons for VOD/SOS and transfusion-resistant thrombocytopenia. [ABSTRACT FROM AUTHOR]

Background Mycosis fungoides ( MF) classically presents from patch stage to plaque stage over a number of years and finally progresses to tumour stage with nodal or visceral involvement. The mechanism of progression remains incompletely elucidated. Chemokines and their receptors are known to be involved in disease mechanisms, with CXCL12 and CXCR4 playing a critical role in carcinogenesis, invasion and cancer cell migration in various carcinomas. Objectives To investigate the expression of CXCL12 and CXCR4 in different cutaneous stages of MF. Methods Formalin-fixed, paraffin-embedded skin samples from 40 patients with MF (21 patch stage, 10 plaque stage, nine tumour stage) and 30 non-neoplastic control skin samples were analysed. CXCL12 and CXCR4 were assessed by quantitative reverse-transcription polymerase chain reaction and immunohistochemical staining. Results The expression level of mRNA for CXCL12 in plaque-stage MF was significantly higher than in control skin ( P = 0·0035), or patch-stage ( P = 0·0108) or tumour-stage disease ( P = 0·0089). The CXCR4 mRNA expression level in plaque-stage disease was significantly higher than in control skin ( P = 0·0090) or patch-stage disease ( P = 0·0387). CXCL12- and CXCR4-positive cell rates in patch-stage and plaque-stage MF were significantly higher than those in control skin ( P < 0·0001). CXCL12- and CXCR4-positve cell rates in tumour-stage MF were significantly lower than those in patch- and plaque-stage disease ( P = 0·0274 and P = 0·0492, respectively). Conclusions Our data suggest that neoplastic T cells in MF are exposed to the microenvironment, given the abundance of CXCL12 during its progression, and also that neoplastic T cells express CXCR4, especially in the pretumour stage. We reveal that the CXCL12- CXCR4 axis plays a critical role in MF progression. [ABSTRACT FROM AUTHOR]