Liver Inflammatory Injury Initiated by DAMPs-TLR4-MyD88/TRIF-NFκB Signaling Pathway Is Involved in Monocrotaline-Induced HSOS.

Hepatic sinusoidal obstruction syndrome (HSOS) causes considerable morbidity and mortality in clinic. Up to now, the molecular mechanisms involved in the development of HSOS still remain unclear. Here, we report that hepatic inflammation initiated by damage-associated molecular patterns (DAMPs) plays a critical role in the development of HSOS. Monocrotaline (MCT) belongs to pyrrolizidine alkaloids. Monocrotaline-induced HSOS in mice and rats was evidenced by the increased serum alanine/aspartate aminotransferase (ALT/AST) activities, the elevated hepatic metalloproteinase 9 (MMP9) expression, and results from liver histological evaluation and scanning electron microscope observation. However, MCT-induced HSOS was markedly attenuated in myeloid differentiation primary response gene 88 (MyD88), TIR-domain-containing adapter-inducing interferon-ß (TRIF) and toll like receptor 4 (TLR4) knock-out mice. Monocrotaline increased liver myeloperoxidase activity, serum contents of proinflammatory cytokines, hepatic aggregation of immune cells, and nuclear accumulation of nuclear factor κB (NFκB). However, these inflammatory responses induced by MCT were all diminished in MyD88, TRIF, and TLR4 knock-out mice. Monocrotaline elevated serum contents of DAMPs including high mobility group box 1 (HMGB1) and heat shock protein 60 (HSP60) both in mice and in rats. HSOS was markedly exacerbated and serum contents of HMGB1 and HSP60 were elevated in nuclear factor erythroid 2-related factor 2 (Nrf2) knock-out mice treated with MCT. Our findings indicate that hepatic inflammatory injury mediated by DAMPs-initiated TLR4-MyD88/TRIF-NFκB inflammatory signal pathway plays an important role in HSOS development.

Phagocytic activity of monocytes, their subpopulations and granulocytes during post-transplant adverse events after hematopoietic stem cell transplantation.

Phagocytosis of granulocytes and monocytes presents a major mechanism that contributes to the clearance of pathogens and cell debris. We analyzed the phagocytic activity of the peripheral blood cell monocytes, three monocyte subpopulations and granulocytes before and up to one year after hematopoietic stem cell transplantation, as well as during transplant-related adverse events. 25 pediatric patients and young adults (median age of 11.0 years) with hemato-oncological malignancies and non malignancies were enrolled in the prospective study. Ingestion of fluorescence-labeled Escherichia coli bacteria was used to assess the phagocytic activity of monocytes and their subpopulations and granulocytes by means of flow cytometry in the patient group as well as in a control group (n=36). During sepsis, a significant increase of phagocytic activity of monocytes (P=0.0003) and a significant decrease of the phagocytic activity of granulocytes (P=0.0003) and the CD14+ CD16++ monocyte subpopulation (P=0.0020) occurred. At the onset of a veno-occlusive disease, a significant increase of phagocytic activity in the CD14++ CD16+ monocyte subpopulation (P=0.001) and a significant decrease in the phagocytic activity of the CD14++ CD16- monocyte subpopulation (P=0.0048) were observed. In conclusion, the phagocytic activity of monocytes, their subpopulations and granulocytes might be a useful and easy determinable parameter that enables identification of post-transplant complications after hematopoietic stem cell transplantation. The alterations of phagocytic activity contribute to the altered immune response that accompanies adverse events after hematopoietic stem cell transplantation.

Cytokine and chemokine patterns across 100 days after hematopoietic stem cell transplantation in children.

We mapped the cytokine response to hematopoietic stem cell transplantation (HSCT) by assaying 51 cytokines and chemokines each week for 100 days in 51 children receiving allogeneic (n = 44) or autologous HSCT (n = 7). Assay values were reported as mean fluorescence intensity (MFI). Log transformation converted MFI to clinically relevant measures (ie, pg/mL). We searched for potential markers of transplant complications by using mixed treatment by subject analysis of variance. Global cytokine secretion in HSCT recipients was significantly lower than in concurrent control patients (n = 11). Coincident with the nadir in WBC count, the concentration of many cytokines declined further by the second and third week. All analytes (except monokine induced by gamma interferon [MIG]) subsequently rebounded by week 4 (coincident with engraftment and recovery of WBC count) but often still remained well below control levels. Concurrent with the collective nadir of multiple cytokines, monocyte chemoattractant protein 1 (MCP-1), growth-regulated oncogene alpha (GRO-a), and leptin surged during weeks 2 to 4. High levels of leptin persisted throughout the 100 post-transplant days. Also during weeks 2 to 4, hepatocyte growth factor (HGF) and IL-6 surged in children with complications but not in those without complications. The peak in HGF was more pronounced in veno-occlusive disease (VOD). HGF and IL-6 secretion rose at least 2 weeks before the clinical diagnosis of VOD or graft-versus-host disease (GVHD). From week 4 onward in all groups, the MFI of the cytokine resistin increased to 5 to 15 times above concurrent control. HGF has now emerged in 3 or more biomarker discovery efforts for GVHD (and in our population for VOD as well). HGF (with or without IL-6) should be investigated as a potential predictive biomarker of VOD or GVHD. Alternatively, the hyperinflammatory "signature" provided by a multicytokine assay may be predictive.

High-dose methylprednisolone for veno-occlusive disease of the liver in pediatric hematopoietic stem cell transplantation recipients.

Veno-occlusive disease (VOD) of the liver is a well-recognized serious complication of hematopoietic stem cell transplantation (HSCT), with few successful treatment modalities available for severe disease. Some reports have demonstrated success in adults with the use of high-dose steroid therapy, but experience in the pediatric population is lacking. We retrospectively reviewed HSCT patients treated at our institution since 2003 and identified 15 (2.4%) who developed VOD. Of these, nine (60%) were treated with intravenous high-dose methylprednisolone (500 mg/m(2) per dose every 12 hours for six doses). Steroid therapy was initiated at or before first ultrasound evidence of reversal of portal venous flow and before meeting criteria for initiation of defibrotide therapy. Four patients were also treated with defibrotide starting 2 to 5 days after initiation of steroids. Eight of nine patients (88%) with VOD were diagnosed with multiorgan failure. Response to high-dose steroid therapy as defined by decrease in bilirubin by 50% in 10 days from therapy initiation was noted in six of nine patients (67%), occurring within 3 to 6 days of steroid therapy. Two patients died from multiorgan failure due to VOD. Seven survivors of VOD recovered at the median 6 days (range, 5 to 38) from VOD diagnosis. Overall, VOD survival as a group was 78%; however, survival among responders was 100%. No serious toxicities related to high-dose steroid therapy were observed. We conclude that high-dose steroid therapy if initiated early may reverse VOD of the liver in pediatric HSCT patients, abrogating the need for defibrotide therapy with its associated toxicities and regulatory difficulties.

Hepatic veno-occlusive disease with immunodeficiency (VODI): first reported case in the U.S. and identification of a unique mutation in Sp110.

Familial hepatic veno-occlusive disease with immunodeficiency (VODI, OMIM: 235550), a rare form of severe combined immune deficiency, was first described in Australian Lebanese patients as being associated with homozygous mutations in SP110, a gene encoding a PML nuclear body-associated protein. We present the first case of confirmed VODI in the United States, and identify the first novel missense mutation in SP110. The 3-year-old daughter of Hispanic parents without known consanguinity presented at age 5 months with fever, hepatomegaly, and pancytopenia. Her brother died at age 3 months from hepatic failure of undetermined etiology. Initial T- and B-cell counts were low, but eventually normalized. Serum IgG and IgM levels were low for age. Lymphoproliferation to mitogens and allogenic B-cells was normal, but absent to tetanus and candida antigens. Serum antibody levels against pneumococcal, Hib and tetanus antigens were low. Liver biopsies at ages 5 and 9 months were consistent with hepatic veno-occlusive disease or hVOD (also known as sinusoidal obstruction syndrome or SOS) and broncho-alveolar lavage detected Pneumocystis jiroveci. The patient recovered from her acute disease and has been clinically stable on immunoglobulin replacement therapy and trimethoprim-sulfamethoxazole prophylaxis. T-Cell receptor excision circle (TREC) analysis suggests that VODI will not be detected by newborn screening for severe combined immunodeficiency that relies on this assay. DNA was obtained from the patient, 4 siblings, and both parents, and SP110 was sequenced. The first missense mutation, a homozygous deletion/insertion variation in exon 2 (NM_080424.2 (SP110):c.78_79delinsAT) was detected in the patient. This novel mutation segregated in the heterozygous state in other living unaffected family members. The mechanism by which this SP110 mutation associates with VODI is consistent with the normal length mutated SP110 protein being subject to enhanced proteosome degradation resulting in marked reductions in SP110 protein.

Clinical, molecular, and cellular immunologic findings in patients with SP110-associated veno-occlusive disease with immunodeficiency syndrome.

BACKGROUND: Mutations in the SP110 gene result in infantile onset of the autosomal recessive primary immunodeficiency disease veno-occlusive disease with immunodeficiency syndrome (VODI), which is characterized by hypogammaglobulinemia, T-cell dysfunction, and a high frequency of hepatic veno-occlusive disease. OBJECTIVES: We sought to further characterize the clinical features, B-lineage cellular immunologic findings, and molecular pathogenesis of this disorder in 9 patients with new diagnoses, including 4 novel mutations from families of Italian, Hispanic, and Arabic ethnic origin. METHODS: Methods used include clinical review; Sanger DNA sequencing of the SP110 gene; determination of transfected mutant protein function by using immunofluorescent studies in Hep-2 cells; quantitation of B-cell subsets by means of flow cytometry; assessments of B-cell function after stimulation with CD40 ligand, IL-21, or both; and differential gene expression array studies of EBV-transformed B cells. RESULTS: We confirm the major diagnostic criteria and the clinical utility of SP110 mutation testing for the diagnosis of VODI. Analysis of 4 new alleles confirms that VODI is caused by reduced functional SP110 protein levels. Detailed B-cell immunophenotyping demonstrated that Sp110 deficiency compromises the ability of human B cells to respond to T cell-dependent stimuli and differentiate into immunoglobulin-secreting cells in vitro. Expression microarray studies have identified pathways involved in B-lymphocyte differentiation and macrophage function. CONCLUSION: These studies show that a range of mutations in SP110 that cause decreased SP110 protein levels and impaired late B-cell differentiation cause VODI and that the condition is not restricted to the Lebanese population.

Veno-occlusive disease/sinusoidal obstruction syndrome associated with potential antibody-mediated rejection after pediatric living donor liver transplantation: a case report.

A 9-month-old girl with biliary atresia underwent successful living donor liver transplantation from her 42-year-old ABO blood-type incompatible mother. The postoperative course was uneventful until postoperative day (POD) 13 when the recipient displayed an increased volume of drained ascites and decreased her platelet count showing low-velocity portal venous inflow without hepatic venous outflow obstruction. We suspected potential veno-occlusive disease/sinusoidal obstruction syndrome (vod/sos) due to an acute cellular rejection (ACR) episode and performed a liver biopsy (LB). We diagnosed severe episode (Rejection Activity Index Score; P3V3B1 = 7) and started steroid pulse therapy. We performed a second LB on POD 27 because the patient showed weight gain and tender hepatomegaly, diagnosing moderate ACR (P1V3B1 = 5). We started a second course of steroid pulse therapy, but the patient's clinical findings did not improve. On POD 43, her third LB finding showed P1V1B1 with improved processes from ACR, but still displaying severe congestion and fibrotic obliteration of small hepatic veins. We suspected that her immunologic responses were associated with antibody-mediated rejection (AMR) because her anti-HLA class I and class II antibodies were positive by flow panel-reactive antibody method and donor-specific antigen class II and C4d staining were also positive. We added mycophenolate mofetil and administered high-dose intravenous immunoglobulin to control the AMR, and anticoagulant therapy for the VOD/SOS. Her clinical findings and graft venous abnormalities finally improved; she was eventually discharged without sequelae on POD 72.

Therapeutic sesamol attenuates monocrotaline-induced sinusoidal obstruction syndrome in rats by inhibiting matrix metalloproteinase-9.

We investigated the therapeutic effect of sesamol against monocrotaline-induced sinusoidal obstruction syndrome (SOS) in rats. Male Sprague-Dawley rats were gavaged with a single dose of monocrotaline (90 mg/kg) to induce SOS. Sesamol (5, 10, 20, and 40 mg/kg) was subcutaneously injected 24 h after monocrotaline treatment. Control rats were given saline only. Aspartate transaminase, alanine transaminase, mast cells, CD 68(+) Kupffer cells, neutrophils, myeloperoxidase, matrix metalloproteinase-9 (MMP-9), tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), laminin, and collagen were assessed 48 h after monocrotaline treatment. All tested parameters, except for TIMP-1, laminin, and collagen, were significantly higher in monocrotaline-treated rats than in control rats, and, except for TIMP-1, laminin, and collagen, significantly lower in sesamol-treated rats than in monocrotaline-treated rats. In addition, liver pathology revealed that sesamol offered significant protection against SOS. We conclude that a single dose of sesamol therapeutically attenuated SOS by decreasing the recruitment of inflammatory cells, downregulating MMP-9, and upregulating TIMP-1 expression.

Order of application and liver toxicity in patients given BU and CY containing conditioning regimens for allogeneic hematopoietic SCT.

BU-CY is the established non-TBI-based myeloablative conditioning regimen for allogeneic hematopoietic SCT. However, liver toxicity and hepatic veno-occlusive disease (VOD) are frequent life-threatening complications. Pharmacological considerations suggest that BU can trigger toxicity of subsequent CY. Recent animal data confirmed this hypothesis. Less liver toxicity and better outcomes were observed when mice were treated with the reversed order of CY and BU. We analyzed in this study liver toxicity and outcome in patients receiving BU-CY (16 patients) or CY-BU (59 patients). Liver function differed significantly with higher levels of liver function tests between day +10 and +30, and a higher cumulative incidence of VOD in the BU-CY cohort (2/16 (12.5%) vs 0/59 (0%), P=0.006). TRM was significantly higher in patients receiving BU-CY (cumulative incidence BU-CY 45%, CY-BU 17%, P=0.02), without yet translating into a significant survival difference (incidence for survival: BU-CY 38%, CY-BU 63%; hazard ratio 1.19 for BU-CY, 95% confidence interval 0.29-4.82, P=0.80). Rates of engraftment and relapse were not different. These data support the concepts derived from animal models in favor of CY-BU compared with traditional BU-CY and form the basis for prospective controlled comparisons.

Veno-occlusive disease of the liver following bone marrow transplantation: a clinical-pathological study of autopsy cases.

A total of 28 patients with leukemia underwent intensive therapy with megadose chemotherapy and stem cell transplantation. Of 16 patients who had busulfan therapy, 2 developed the clinical syndrome of veno-occlusive disease of the liver (VOD) characterized by progressive abnormalities in liver function, abdominal pain, and ascites. Postmortem findings showed VOD of the central and sublobular hepatic vein. Immunohistochemical analysis using anti-actin and CD34 mAb was employed in an attempt to clarify the process of fibrosis. Actin positive cells had accumulated around the central vein. Ito cell activation might be responsible for secondary fibrosis following endothelial injury. We report autopsy findings and immunohistochemical results.

Allogeneic liver transplantation for hepatic veno-occlusive disease after bone marrow transplantation--clinical and immunological considerations.

Veno-occlusive disease (VOD) is a frequent complication early after bone marrow transplantation. In cases of severe liver failure treatment by allogeneic liver transplantation is possible. We report the clinical and immunological course of a patient after bone marrow transplantation for AML and subsequent allogeneic liver transplantation for severe hepatic VOD. After liver transplantation the patient recovered well clinically. Early after liver transplantation he had large numbers of liver donor T and NK lymphocytes in his circulation. He had no liver graft rejection, but he developed mild acute GVHD which was caused by liver graft-derived T lymphocytes. Two years after transplantation he had persistent microchimerism with donor liver cells detectable in his bone marrow. Now 36 months after transplantation, the patient has no evidence of recurrent leukemia, stable liver function, and no signs of graft-versus-host disease or bone marrow dysfunction.

Transforming growth factor beta as a predictor of liver and lung fibrosis after autologous bone marrow transplantation for advanced breast cancer.

BACKGROUND: Hepatic veno-occlusive disease and idiopathic interstitial pneumonitis are major causes of morbidity and mortality after bone marrow transplantation. Fibrosis is a characteristic of both conditions, and transforming growth factor beta (TGF beta) has been implicated in the pathogenesis of fibrosis. METHODS: Using acid-ethanol extraction to remove TGF beta from human plasma and a mink-lung epithelial-cell growth-inhibition assay to measure TGF beta activity, we quantified plasma TGF beta in 10 normal subjects and 41 patients before and after they underwent high-dose chemotherapy and autologous bone marrow transplantation for advanced breast cancer. RESULTS: There was no difference in pretransplantation TGF beta levels between the controls and the patients who did not have hepatic veno-occlusive disease or idiopathic interstitial pneumonitis after transplantation. In contrast, pretransplantation TGF beta levels were significantly higher in patients in whom hepatic veno-occlusive disease or idiopathic interstitial pneumonitis developed than in the controls or the patients without these conditions. The predictive value for the development of either condition was 90 percent or more when pretransplantation plasma TGF beta levels were more than 2 SD above the mean established in the controls. CONCLUSIONS: The plasma TGF beta concentration measured after induction chemotherapy but before high-dose chemotherapy and autologous bone marrow transplantation strongly correlates with the risk of hepatic veno-occlusive disease and idiopathic interstitial pneumonitis after these treatments.