Endogenous protease inhibitor uptake within the graft during reperfusion in human liver transplantation

BACKGROUND

In experimental liver transplantation, endogenous protease inhibitors alleviate ischemia-reperfusion (I/R) injury by inhibiting proteolysis and by direct anti-inflammatory actions. We described the kinetics of endogenous protease inhibitors and explored their anti-inflammatory potential during reperfusion and their effects on graft function in human liver transplantation.

METHODS

We measured circulating levels of protease inhibitors (secretory leukocyte proteinase inhibitor, SLPI; tissue inhibitor of metalloproteinases-1, TIMP-1) and proteolytic enzymes (elastase; matrix metalloproteinase-9, MMP-9) with ELISA, and neutrophil and monocyte CD11b and L-selectin expression with flow cytometry during liver transplantation in ten patients. To assess changes within the graft during reperfusion, blood samples from portal and hepatic veins were obtained simultaneously.

RESULTS

Circulating SLPI and TIMP-1 levels decreased during surgery. During initial reperfusion, the transhepatic SLPI gradient was -27 (-35 to -22) ng/ml, P = 0.005, and TIMP-1 -510 (-636 to -362) ng/ml, P = 0.005, indicating graft protease inhibitor uptake. Concomitantly, hepatic phagocyte activation and sequestration as well as elastase and MMP-9 release into the circulation occurred. The transhepatic SLPI gradient correlated with postoperative liver enzymes (ALT R = -0.648, P = 0.043; ALP R = -0.661, P = 0.038; bilirubin R = -0.821, P = 0.004; GGT R = -0.648, P = 0.043).

CONCLUSIONS

The results suggest a relative shortage of protease inhibitors within the liver during reperfusion, which may contribute to the development of graft injury.

Tuberculosis of the colon in a kidney transplant patient

A 58-year-old woman experienced recurrent fever episodes after kidney transplantation. She was treated with antibiotics because of suspicion of staphylococcus infection. Abdominal pain combined with haemorrhagic diarrhoea occurred eight months after transplantation. A barium enema revealed a stenotic process in the middle part of the ascending colon mimicking carcinoma, and hemicolectomy was consequently performed. Histological examination revealed tuberculosis with little granuloma formation and abundant acid-fast tubercle bacilli in the mucosa and submucosa, and only slight perigranulomatous reactions. The patient was successfully treated with triple antituberculous chemotherapy without deterioration of allograft function. Tuberculosis should be suspected in immunosuppressed patients suffering from pyrexia of unknown origin, even when chest X-ray is normal.

Hepatic IL-8 release during graft procurement is associated with impaired graft function after human liver transplantation

In experimental models, brain death induces inflammatory cascades, leading to reduced graft survival. Thus far, factors prior to graft preservation have gained less attention in clinical setting. We studied pre-preservation inflammatory response and its effects on graft function in 30 brain dead liver donors and the respective recipients. Before donor graft perfusion, portal and hepatic venous blood samples were drawn for phagocyte adhesion molecule expression and plasma cytokine determinations. Donor intensive care unit stay correlated with donor C-reactive protein (R = 0.472, p = 0.013) and IL-6 (R = 0.419, p = 0.026) levels, and donor (R = 0.478, p = 0.016) and recipient gamma-glutamyl transferase (R = 0.432, p = 0.019) levels. During graft procurement, hepatic IL-8 release was observed in 17/30 donors. Grafts with hepatic IL-8 release exhibited subsequently higher alkaline phosphatase [319 (213-405) IU/L vs. 175 (149-208) IU/L, p = 0.006] and bilirubin [101 (44-139) micromol/L vs. 30 (23-72) micromol/L, p = 0.029] levels after transplantation. Our findings support the concept that inflammatory response in the brain dead organ donor contributes to the development of graft injury in human liver transplantation.

Health-related quality of life and employment status of liver transplant patients

Health-related quality of life (HRQoL) is one preferable outcome measure of medical interventions such as liver transplantation (LT). The aim of this study was to compare HRQoL of LT patients with that of the general population and to assess the employment status of LT patients. HRQoL was measured with the 15D instrument, a validated, non-disease-specific, 15-dimensional, self-administered HRQoL instrument. The questionnaire was sent to all adult LT patients in Finland (401 patients) alive in June 2007. The response rate was 89% (353 patients). The results were compared to those of 6050 age-standardized and gender-standardized controls from the general population. LT patients (mean age, 55 years; range, 20-82) had slightly worse HRQoL scores than the general population (mean 15D score, 0.889 versus 0.907; P < 0.002). Survival time and retransplantation did not affect HRQoL significantly in age-adjusted and gender-adjusted analyses. HRQoL decreased with increasing age (P < 0.0001). Patients transplanted for acute liver failure (ALF) or chronic liver disease (CLD) had significantly worse HRQoL than the general population (P = 0.014 and P = 0.040). Forty-four percent of working-age patients were employed at the time of the study. Persons that were employed had significantly better HRQoL than those unemployed (15D scores, 0.934 versus 0.859; P < 0.0001). Eighty-seven percent of patients experienced improved working capacity after LT. Early retirement was the most common cause of unemployment (56% of unemployed patients), and those patients presented with worse HRQoL than patients unemployed for other reasons. In conclusion, HRQoL of LT patients is very close to that of the general population. Older age, CLD, and ALF impair HRQoL. Employment is an indicator of HRQoL.

Albumin dialysis has a favorable effect on amino acid profile in hepatic encephalopathy

According to one popular theory, hepatic encephalopathy (HE) is partly caused by an imbalance in plasma amino acid levels. The Fischer's ratio between branched chain amino acids (BCAAs) and aromatic amino acids (AAAs) correlates with the degree of HE; the lower Fischer's ratio, the higher the grade of HE. Extra-corporeal liver support systems, like MARS(R)-albumin dialysis (Molecular Adsorbents Recirculating System), can improve HE. The MARS(R) system uses a hyperosmolar albumin circuit to remove both water-soluble and albumin-bound substances. Plasma levels of neuroactive amino acids were analyzed in 82 consecutive patients with life-threatening liver failure admitted to our ICU. All patients fulfilled our indications for MARS treatment and most also fulfilled the criteria for liver transplantation (LTx). In patients with acute liver failure (ALF), as compared to those with acute decompensation of chronic liver failure (AcOChr), levels of leucine and isoleucine were significantly higher before MARS(R) treatment. In all patients, before MARS(R) treatment the higher the grade of HE grade the lower was the Fischer's ratio and higher were the levels of inhibitory neuroactive amino acids. During MARS(R) treatments the Fischer's ratio increased, and the grade of HE decreased. The increase in Fischer's ratio was mainly due to the decrease in AAAs. The plasma levels of neuroactive amino acids, methionine, glutamine, glutamate, histidine and taurine decreased during MARS(R)-treatment. In this study MARS(R)-albumin dialysis had a favorable effect on the plasma amino acid profile of patients with HE.

High mobility group box 1 protein as a marker of hepatocellular injury in human liver transplantation

High mobility group box 1 protein (HMGB1), a cytokine actively secreted by phagocytes and passively released from necrotic cells, is an inflammatory mediator in experimental hepatic ischemia/reperfusion injury. We characterized its expression in human liver transplantation. In 20 patients, in addition to systemic samples, blood was drawn from portal and hepatic veins during and after reperfusion to assess changes within the graft. Plasma HMGB1, tumor necrosis factor alpha (TNF-alpha), and interleukin-6 (IL-6) levels were measured, and HMGB1 immunohistochemistry was performed on biopsies taken before and after reperfusion. Plasma HMGB1 was undetectable before reperfusion, and levels in systemic circulation peaked after graft reperfusion. At portal declamping, HMGB1 levels were substantially higher in the caval effluent [188 (80-371) ng/mL] than in portal venous blood [0 (0-3) ng/mL, P < 0.001]. HMGB1 release from the graft continued thereafter. HMGB1 levels were not related to TNF-alpha or IL-6 levels. HMGB1 expression was up-regulated in biopsies taken after reperfusion (P = 0.020), with intense hepatocyte and weak neutrophil staining. HMGB1 levels in hepatic venous blood correlated with graft steatosis (r = 0.497, P = 0.03) and peak postoperative alanine aminotransferase levels (r = 0.588, P = 0.008). Our results indicate that HMGB1 originates from the graft and is a marker of hepatocellular injury in human liver transplantation.

Inhibition of Semicarbazide-Sensitive Amine Oxidases Decreases Lymphocyte Infiltration in the Early Phases of Rat Liver Allograft Rejection

Vascular adhesion protein-1 (VAP-1) has been shown to mediate lymphocyte adhesion to endothelia at sites of inflammation in vitro and in vivo. VAP-1 is also an ectoenzyme with semicarbazide-sensitive amine oxidase (SSAO) activity. In this study we investigated whether inhibition of SSAO influences the inflammatory infiltration in acute rat liver allograft rejection. BN recipients of DA liver allografts were treated with 50 mg/kg/d semicarbazide, an inhibitor of SSAO, or similar volumes of saline. 10 rats/group were followed for graft survival, and 10 rats/group were sacrificed on day 7 post-transplantation for histology and T-lymphocyte isolation. The area percentage of portal inflammatory infiltrates in the grafts was assessed from digital photomicrographs. The proportion of CD4-, CD8- and IL2-receptor positive lymphocytes in the graft was quantified with flow cytometry. On day 7, semicarbazide treatment significantly decreased the inflammatory infiltrate area in the grafts. CD4-, CD8- and IL2-receptor positive cells were equally affected. However, animal survival was not affected. Blockade of the enzymatic activity of VAP-1 has a significant effect on lymphocyte infiltration early in acute liver rejection. Later, activation of other adhesion pathways can by-pass the blockade caused by VAP-inhibition.

Risk of malignant neoplasms after liver transplantation: a population-based study

Posttransplant malignancies have become a serious long-term complication after liver transplantation. Our aim was to compare the incidence of posttransplant cancers with national cancer incidence rates. The study included all Finnish liver transplant patients transplanted at the Helsinki University Central Hospital between 1982 and 2005. The cohort was linked with the nationwide Finnish Cancer Registry. Observed numbers of cancers were compared to site-specific expected numbers based on national cancer incidence rates stratified by age, sex, and calendar time. The standardized incidence ratios (SIRs) were calculated as observed-to-expected ratios. Thirty-nine posttransplant de novo cancers and 11 basal cell carcinomas were found in the cohort of 540 patients during 3222 person years of follow-up. The overall SIR was 2.59 (95% confidence interval 1.84-3.53). SIR was higher for males (SIR 4.16) than for females (SIR 1.74), higher among children (SIR 18.1) than among adults (SIR 5.77 for ages of 17-39 years and 2.27 for ages >/= 40 years), and more elevated in the immediate posttransplant period (SIR 3.71 at < 2 years) compared to later periods (SIR 2.46 at 2-10 years and 1.53 at >10 years). The most common cancer types were nonmelanoma skin cancer (SIR 38.5) and non-Hodgkin lymphoma (SIR 13.9). Non-Hodgkin lymphoma was associated with male gender, young age, and the immediate posttransplant period, whereas old age and antibody induction therapy increased skin cancer risk. In conclusion, cancer incidence is increased among liver transplant patients compared to the general population. This study points out the importance of cancer surveillance after liver transplantation.

The effect of molecular adsorbent recirculating system treatment on survival, native liver recovery, and need for liver transplantation in acute liver failure patients

Acute liver failure (ALF) is a medical emergency. Molecular adsorbent recirculating system (MARS), an artificial liver support system, can partly compensate for the detoxifying function of the liver by removing toxins from blood. To analyze the efficacy of MARS treatment, the outcomes of 113 ALF patients, treated with MARS between 2001 and 2007, were compared with a historical control group of 46 ALF patients treated without MARS between 1995 and 2001. Overall survival of transplanted patients was 94% in the MARS group and 77% in the control group (P=0.06). Without transplantation, survival was 66% and 40% (P=0.03), respectively. However, the etiological distribution of ALF differed significantly between the groups. In ALF patients with unknown etiology, groups were comparable at baseline; 91% and 69% of transplanted patients survived the MARS and control groups and the native liver recovered in 20% and 8% of the patients, respectively. Of the originally nonencephalopathic patients of unknown etiology, 36% underwent liver transplantation in the MARS group compared to 100% in the control group. Interpretation of the results was difficult in toxic etiology patients on account of differing baseline statuses. MARS treatment might partly explain the trend toward increased survival of ALF patients with unknown etiology.

Cytokine profiles in acute liver failure treated with albumin dialysis

Cytokines are released within the liver in response to hepatic injury, and acute liver failure (ALF) triggers systemic inflammation. Pro-inflammatory (tumor necrosis factor-alpha [TNF-alpha] and interleukin-8 [IL-8]) and anti-inflammatory (interleukin-10 [IL-10] and interleukin-6 [IL-6]) cytokines and the lymphocyte activation marker (interleukin-2-soluble receptor alpha chain [IL-2sRalpha]) were monitored in 49 ALF patients considered for liver transplantation and treated with albumin dialysis (molecular adsorbent recirculating system [MARS]). Twenty-six patients were categorized by clinical outcome as "good" (native liver recovered) and 23 as "poor" (patient bridged to liver transplantation or deceased). MARS did not clearly affect cytokine profiles during treatment; only IL-10 levels decreased in the whole patient population and mostly in patients with the worst prognosis. In the good outcome group, IL-8 and IL-6 levels decreased during treatment; on the contrary, in poor outcome patients IL-6 levels even increased. Initial IL-2sRalpha levels were higher in poor outcome patients relative to the good outcome subset. Cytokine profiles seem to differ in ALF according to patient outcome. A deeper understanding of cytokine patterns during pathogenesis could reveal prognostic markers and aid the development of immunomodulating ALF therapies.

Enhanced detection of cholangiocarcinoma with serum trypsinogen-2 in patients with severe bile duct strictures

BACKGROUND/AIMS

Primary sclerosing cholangitis (PSC) is associated with a high risk of cholangiocarcinoma. Our aim was to evaluate the diagnostic value of trypsinogen-1, trypsinogen-2, tumour-associated trypsin inhibitor, human chorionic gonadotropin beta and trypsin-2-alpha(1)-antitrypsin for cholangiocarcinoma and to compare them with CA19-9 and CEA.

METHODS

The study consisted of 84 patients with either PSC or cholangiocarcinoma or both referred for liver transplantation or other liver surgery. The serum concentrations were determined by time-resolved immunofluorometric assays.

RESULTS

Forty-six patients were transplanted due to PSC; in 3 of the explanted livers cholangiocarcinoma was found incidentally. All transplanted patients had severe biliary strictures together with cirrhosis or pre-cirrhosis. Twenty-nine of 38 patients with cholangiocarcinoma were candidates for intervention. In all, 8 patients had both PSC and cholangiocarcinoma. Receiver-operating characteristics curve analysis showed that serum trypsinogen-2 had the highest accuracy in differentiating between cholangiocarcinoma and PSC. The area under the curve (AUC) value was 0.804 for trypsinogen-2 and 0.613 for CA19-9. Serum trypsinogen-2 also showed the highest accuracy for differentiation between PSC and PSC with simultaneous cholangiocarcinoma with an AUC value of 0.759.

CONCLUSIONS

Our results suggest that serum trypsinogen-2 is a most useful marker for diagnosing patients with cholangiocarcinoma, and it is superior to serum CA19-9 and CEA.

High serum soluble CD30 does not predict acute rejection in liver transplant patients

Increased pre- and posttransplantation values of soluble CD30 (sCD30) have been shown to be associated with acute kidney transplant rejection. We sought to study whether high sCD30 could predict rejection early after liver transplantation. The study population included 54 consecutive liver transplant patients, whose samples were collected before liver transplantation and at discharge, which was at a mean time of 3 weeks after transplantation. During the first 6 months posttransplantation, 22 patients experienced an acute rejection episode. Serum sCD30 concentrations were measured by an enzyme-linked immunoassay; changes in serum sCD30 levels posttransplantation were also expressed as relative values compared with pretransplantation results. Liver patients before transplantation displayed higher serum sCD30 values compared with healthy controls: mean values +/- SD were 93 +/- 58 IU/mL vs 17 +/- 8 IU/mL, respectively. At 3 weeks after transplantation the mean sCD30 concentration in liver transplant patients decreased to 59 +/- 42 IU/mL (P = .005). The mean pretransplantation serum sCD30 value was slightly lower among rejecting vs nonrejecting patients: 78 +/- 43 IU/mL vs 104 +/- 65 IU/mL (P = NS). Posttransplantation values in both groups decreased significantly: 47 +/- 34 IU/mL in patients with rejection (P = .014) vs 69 +/- 45 IU/mL in patients without rejection (P = .012). The relative value at 3 weeks posttransplantation decreased slightly more among patients with vs without rejection (70% vs 88%; NS). No correlation was found between serum sCD30 and anti-HLA class I antibodies or crossmatch positivity. In conclusion, neither pre- nor posttransplantation sCD30 levels were associated with acute rejection in liver transplant patients.

Albumin dialysis has no clear effect on cytokine levels in patients with life-threatening liver insufficiency

Cytokines play a important role in life-threatening liver insufficiency. They are released within the liver in response to hepatic injury and inflammation. To study cytokine clearance during albumin dialysis treatment (Molecular Adsorbent Recirculating System [MARS]), we monitored proinflammatory (tumor necrosis factor alpha [TNF-alpha] and interleukin-8 [IL-8]) and anti-inflammatory (IL-10 and IL-6) cytokines and the lymphocyte activation marker IL-2sRalpha in 81 consecutive ICU patients displaying serious hepatic decompensation. Cytokine levels were measured before treatment and after the last MARS treatment in 49 acute liver failure (ALF) and 32 acute decompensation of chronic liver disease (AcOChr) patients who were mainly considered for liver transplantation. No significant change in cytokines was observed before versus after the last MARS treatment in the AcOChr group, and only IL-10 decreased significantly in the ALF group. Baseline levels of IL-8 and IL-6 were significantly lower and IL-10 was higher in the ALF group compared with those in the AcOChr group. TNF-alpha and IL-2sRalpha levels did not differ between the groups. After treatment, IL-8 was also significantly lower in ALF patients compared with the levels in AcOChr patients. In this study, MARS therapy did not show a clearly identifiable efficacy at removing circulating cytokines. However, the results revealed that ALF and AcOChr patients displayed different profiles of circulating cytokines.

Renal dysfunction in liver transplant patients: comparing patients transplanted for liver tumor or acute or chronic disease

Liver transplant patients are susceptible to renal dysfunction through a number of mechanisms. Our aim was to investigate if renal function differs among transplant indication groups. Consecutive liver transplantations (396) were divided in three groups: 277 with chronic liver disease (CLD), 90 with acute liver failure (ALF), and 29 with liver tumor. Data were recorded before and after transplantation. The glomerular filtration rate (GFR) was based on Cockcroft-Gault formula and renal function staged using the National Kidney Foundation guidelines. On the transplantation day, 4%, 15%, and 0% of patients in the CLD, ALF, and tumor groups, respectively, showed severely decreased GFR (</=29 ml/min/1.73 m(2)). The percentage with moderately or severely decreased GFR (<60 ml/min/1.73 m(2)) increased steadily in the CLD group (46% at 5 years) but decreased in the ALF group from the transplantation day (26% at 5 years). Of patients with moderately or severely decreased GFR at listing, 73% of the CLD and 35% of ALF patients continued to exhibit it at 1 year. The cumulative incidence of chronic renal failure was 16% at 10 years. MELD scores did not show notable correlation with post-transplant GFR. Renal dysfunction prior to transplantation often improved post-transplant in ALF patients, but was often irreversible in CLD patients. In CLD and tumor patients, renal function steadily deteriorated post-transplant.

Chlorpromazine and apigenin reduce adenovirus replication and decrease replication associated toxicity

BACKGROUND

Adenoviruses can cause severe toxicity in immunocompromised individuals. Although clinical trials have confirmed the potency and safety of selectively oncolytic adenoviruses for treatment of advanced cancers, increasingly effective agents could result in more toxicity and therefore it would be useful if replication could be abrogated if necessary.

METHODS

We analyzed the effect of chlorpromazine, an inhibitor of clathrin-dependent endocytosis and apigenin, a cell cycle regulator, on adenovirus replication and toxicity. First, we evaluated the in vitro replication of a tumor targeted Rb-p16 pathway selective oncolytic adenovirus (Ad5/3-Delta24) and a wild-type adenovirus in normal cells, fresh liver samples and in ovarian cancer cell lines. Further, we analyzed the in vitro cell killing efficacy of adenoviruses in the presence and absence of the substances. Moreover, the effect on in vivo efficacy, replication and liver toxicity of the adenoviruses was evaluated.

RESULTS

We demonstrate in vitro and in vivo reduction of adenovirus replication and associated toxicity with chlorpromazine and apigenin. Effective doses were well within what would be predicted safe in humans.

CONCLUSIONS

Chlorpromazine and apigenin might reduce the replication of adenovirus, which could provide a safety switch in case replication-associated side effects are encountered in patients. In addition, these substances could be useful for the treatment of systemic adenoviral infections in immunosuppressed patients.

Pharmacokinetics of ropivacaine in patients with chronic end-stage liver disease

BACKGROUND

Ropivacaine is mainly eliminated by hepatic metabolism. The authors studied the effect of chronic end-stage liver disease on the pharmacokinetics of ropivacaine.

METHODS

Thirteen patients with chronic end-stage liver disease and eight healthy volunteers received a single dose of 0.6 mg/kg ropivacaine intravenously over 30 min. Ropivacaine, 3-hydroxyropivacaine, and 2',6'-pipecoloxylidide were measured in venous plasma and urine.

RESULTS

Peak ropivacaine plasma concentrations were similar. Patients with chronic end-stage liver disease had, on average, 60% lower total (P=0.001) and 56% lower unbound plasma clearance (P=0.002), 59% higher steady state volume of distribution (P=0.03), and 4.2-fold longer half-life (P<0.001) of ropivacaine. Of the variation in total ropivacaine clearance, 69% was accounted for by variation in albumin, 57% in prealbumin, 25% in international normalized ratio of plasma thromboplastin time, and 24% in galactose half-life. The patients excreted a larger fraction of the original dose as unchanged ropivacaine (2.1% vs. 0.3%; P<0.001) and a smaller fraction as 3-hydroxyropivacaine (11% vs. 27%; P=0.001). The fraction excreted as 2',6'-pipecoloxylidide (4.7% vs. 5.0%) was similar.

CONCLUSIONS

Ropivacaine clearance is decreased in chronic end-stage liver disease. A normal dose can be considered for a single block in patients with liver impairment, because the peak plasma concentrations were essentially similar. When using a postoperative ropivacaine infusion in a patient with end-stage liver disease, the lowest effective dose should be used for the shortest possible time and the patient should be monitored closely, because systemic toxicity cannot be ruled out. Because of wide interindividual differences in pharmacokinetics in patients with liver disease, no definitive dosing instructions can be given.

HHV-6 DNA in peripheral blood mononuclear cells after liver transplantation

BACKGROUND

Human herpesvirus-6 (HHV-6) infections have been reported after liver transplantation. In this study, the detection of HHV-6 DNA in peripheral blood mononuclear cells (PBMC) was compared with HHV-6 antigenemia in liver transplant patients.

OBJECTIVES

Forty-three adult liver recipients were frequently monitored by HHV-6 antigenemia test, which detects the viral antigens in PBMC, but is rather qualitative than quantitative.

STUDY DESIGN

From the same PBMC specimens HHV-6 DNA was demonstrated by in situ hybridization using a biotinylated probe and quantified as positive cells/10, 000 PBMC. Altogether 330 blood specimens were analyzed.

RESULTS

During the first 6 months (mean 12 days) after transplantation, 35/43 patients developed HHV-6 antigenemia. Concurrently, HHV-6 DNA-positive cells with mean peak number of 661(+/-574)/10, 000 were detected in 33/35 patients. Seven patients received ganciclovir treatment because of concurrent CMV infection with mean peak number of HHV-6 DNA-positive cells 381(+/-336) before and 34(+/-59)/10, 000 after the treatment (p = 0.03). All CMV infections responded to ganciclovir, but HHV-6 DNAemia disappeared slowly, within 79 days (mean 36 days). Without antivirals, HHV-6 DNAemia/antigenemia lasted usually longer.

CONCLUSIONS

Detection of HHV-6 DNA in PBMC correlated well with HHV-6 antigenemia, and may be used in the monitoring of transplant patients.

Monitoring of EBV-DNAemia by quantitative real-time PCR after adult liver transplantation

BACKGROUND

Post-transplant lymphoproliferative disease (PTLD) causes significant morbidity and mortality in transplantation. The clinical significance of Epstein-Barr virus (EBV) in the development of PTLD is clear, but not all EBV-reactivations cause PTLD.

OBJECTIVES

We retrospectively analyzed EBV-DNAemia in liver transplant patients by a quantitative TaqMan-based real-time plasma PCR.

STUDY DESIGN

Altogether 1284 specimens, obtained from 105 patients for frequent monitoring of cytomegalovirus (CMV) and human herpesvirus-6 and -7 (HHV-6, HHV-7) during the post-transplant year, were retrospectively tested for EBV-DNA.

RESULTS

Altogether, 14/105 (13%) patients showed EBV-DNAemia, which usually occurred within 3 months after transplantation and subsided within a few weeks. EBV-DNAemia occurred concurrently with CMV in 10/14, with HHV-6 in 11/14, and with all three betaherpesviruses in 4/14 cases. The peak viral loads were relatively low (median 2100 EBV-DNA copies/ml, range 568-6600), except in one patient who first had low-level EBV-DNA (562-3022 copies/ml) in the early post-transplant period, but on day 175 after transplantation developed high-level DNAemia (9851-86,975copies/ml) which continued for 6 months and developed into PTLD at 6 months after transplantation.

CONCLUSION

Low-level EBV-DNAemia is common after liver transplantation, often occurring together with betaherpesviruses, but seldom leads to high viral loads or PTLD. However, monitoring of EBV-DNA levels in the patients can be useful.

Infectivity-enhanced adenoviruses deliver efficacy in clinical samples and orthotopic models of disseminated gastric cancer

PURPOSE

Metastatic gastric cancer remains a common and devastating disease without curative treatment. Recent proof-of-concept clinical trials have validated gene therapy with adenoviruses as an effective and safe modality for the treatment of cancer. However, expression of the primary coxsackie-adenovirus receptor is variable in advanced cancers, and therefore, the use of heterologous receptors could be advantageous.

EXPERIMENTAL DESIGN

Here, we used capsid-modified adenoviruses for increasing the transduction and subsequent antitumor efficacy. 5/3 chimeric viruses have a serotype 3 knob which allows binding to a receptor distinct from coxsackie-adenovirus receptor. The fiber of Ad5lucRGD is modified with an integrin-targeted motif. Polylysine motifs, pK7 and pK21, bind to heparan sulfates. Oncolytic adenoviruses replicate in and kill tumor cells selectively. Gastric cancer cell lines and fresh clinical samples from patients were infected with transductionally targeted viruses. Capsid-modified oncolytic adenoviruses were used in cell killing experiments. To test viral transduction and therapeutic efficacy in vivo, we developed orthotopic mouse models featuring i.p. disseminated human gastric cancer, which allowed the evaluation of biodistribution and antitumor efficacy in a system similar to humans.

RESULTS

Capsid modifications benefited gene transfer efficiency and cell killing in gastric cancer cell lines and clinical samples in vitro and in vivo. Modified oncolytic adenoviruses significantly increased the survival of mice with orthotopic gastric cancer.

CONCLUSIONS

These preclinical data set the stage for the clinical evaluation of safety and efficacy in patients with disease refractory to current modalities.

Cytomegalovirus infection of the liver transplant: virological, histological, immunological, and clinical observations

The most common organ-specific manifestation of cytomegalovirus (CMV) infection after liver transplantation is hepatitis. Here we retrospectively describe the detailed virological, histological, immunological, and clinical findings associated with CMV infection in 229 consecutive adult liver transplantation patients. CMV infection was diagnosed by pp65 antigenemia. From 439 liver biopsies, CMV antigens were demonstrated by immunohistochemistry and CMV DNA by hybridization. The Banff criteria were used for histology. The expression of various adhesion molecules (intercellular adhesion molecule-1 [ICAM-1], vascular cell adhesion molecule-1 [VCAM-1], endothelial leukocyte adhesion molecule-1 [ELAM-1]), their ligands (leukocyte function antigen-1 [LFA-1], very late antigen-4 [VLA-4], Sialyl-LewisX-molecule [SLeX]), and lymphoid activation markers (major histocompatibility complex [MHC] Class II, interleukin-2-receptor [IL-2R]) was demonstrated by immunohistochemistry. CMV infection of the transplant occurred in 26 patients (11% of all 229 patients and 17% of the 151 patients with liver biopsy). The incidence was higher among seronegative (26%) than in seropositive recipients (9%), but most cases 18/26 (70%) were reactivations. The CMV pp65 antigenemia levels were usually high in primary infections (893+/-1069, range 50-3000 pp65+cells), but varied widely in reactivations (388+/-740, range 3-3000). The histological Banff score was slightly increased (2.3+/-0.9). Microabscesses, lymphocytic infiltration, Kupffer cell reaction, and parenchymal alterations were common but viral inclusions rare. CMV significantly (P<0.05) increased ICAM-1 and VCAM-1 expression and the number of LFA-1, VLA-4, and Class II-positive lymphocytes in the graft. All CMV infections were successfully treated with antivirals. Intragraft CMV infection had no influence on the long-term outcome, but biliary complications were common. In conclusion, CMV infection of the liver transplant occurred both in primary infection and in reactivation, and also in the cases with low pp65 antigenemia levels. Microabscesses and other histological alterations were common but viral inclusions rare. Increased adhesion molecule expression was associated with lymphocyte infiltration. Successfully treated CMV hepatitis had no influence on the long-term clinical outcome.