Prognostic significance of intratumoural microvessel density (IMD) in resected pancreatic and ampullary cancers to standard histopathological variables and survival

AIM

Angiogenesis is required for tumour growth. Its evaluation, by intratumoural microvessel density (IMD), has prognostic significance in many solid tumours. There is controversy regarding its use in pancreatic cancer and little is known about its role in ampullary tumours. The aim is to study IMD as a prognostic marker in resected ductal adenocarcinomas of head of pancreas and cancers of the ampullary region.

METHODS

Forty-seven patients (23 pancreatic and 24 ampullary, mean age 62.0 years) surviving a potentially curative (R0/R1) resection were analysed. Paraffin-embedded sections of these tumours were immunohistochemically stained for CD-34 and IMD was determined (magnification x200). This was correlated with histopathological data and survival using Cox's multivariate analysis.

RESULTS

Mean survival for the pancreatic cancer group was 18.4 months (SE=2.7) and 81.2 months (SE=9.9) for the ampullary cancer group. In the pancreatic cancer group, IMD was found to have independent prognostic significance to survival on multivariate analysis (P=0.002, Hazard Ratio (HR) 13.60) along with microscopic resection margin involvement (P=0.003, HR 15.18). For ampullary cancers, IMD was higher in those with lymph node metastasis (P=0.02, Mann-Whitney U -test).

CONCLUSION

IMD in resected pancreatic cancers correlates with survival.

Moderate alcohol intake increases fibrosis progression in untreated patients with hepatitis C virus infection

Although excessive alcohol consumption in combination with hepatitis C virus (HCV) infection is known to increase the risk of liver cirrhosis, the effect of moderate alcohol intake remains to be elucidated. The aim of this study was to evaluate the effect of moderate alcohol consumption on fibrosis progression in HCV infection. A group of 78 patients with HCV infection and moderate alcohol consumption were analysed retrospectively. All patients had undergone two liver biopsies, with a median time between biopsies of 6.3 years, and had not received any antiviral therapy. Their lifetime drinking history was recorded. All patients except one had daily alcohol consumption below 40 g of ethanol (median 4.8 g/day, interquartile range 1.1-11.6 g/day) during the period between the biopsies. The patients whose liver fibrosis had deteriorated had a higher total alcohol consumption and higher drinking frequency between the biopsies. The degree of fibrosis progression was greater in patients with a total alcohol intake and drinking frequency above the median level for the group. A multiple logistic regression analysis showed that drinking frequency and time between biopsies were independently associated with fibrosis progression. Hence, even moderate alcohol intake seems to increase fibrosis progression in HCV-infected patients. From that point of view, total abstention ought to be recommended. If this is not achieved, occasional use of alcohol is probably less harmful than daily drinking for patients with low or moderate alcohol consumption.

A pilot study of treatment of active ulcerative colitis with natalizumab, a humanized monoclonal antibody to alpha-4 integrin

BACKGROUND

Alpha-4 integrins facilitate leucocyte migration across vascular endothelium.

AIM

To assess the safety and efficacy of natalizumab (Antegren), a humanized antibody to alpha-4 integrin, in patients with active ulcerative colitis.

METHODS

Ten patients with active ulcerative colitis, defined by a Powell-Tuck activity score > 4, received a single 3 mg/kg natalizumab infusion. The primary end-point was the change in Powell-Tuck score at 2 weeks post-infusion.

RESULTS

Significant decreases in the median Powell-Tuck score were observed at 2 and 4 weeks post-infusion (7.5 and 6, respectively) compared to the median baseline score (10). Five of 10 patients achieved a good clinical response at 2 weeks and one more patient by 4 weeks, defined by a Powell-Tuck score of < or = 5. Significant improvements in quality of life scores were found at week 4. Rescue medication was required by two (20%), three (30%) and eight (80%) patients by weeks 2, 4 and 8, respectively (median, 34 days; range, 8-43 days). One patient remained in remission at 12 weeks. The median C-reactive protein at 2 weeks (6 mg/L) was lower than that pre-treatment (16 mg/L).

CONCLUSIONS

A single 3 mg/kg infusion of natalizumab was well tolerated by ulcerative colitis patients. The positive efficacy demonstrated in this study merits further investigation by randomized, placebo-controlled trials.

Histological patterns of rejection using oral microemulsified cyclosporine and tacrolimus (FK506) as monotherapy induction after orthotopic liver transplantation

BACKGROUND/AIMS

We describe the histological patterns of rejection in liver transplant recipients using induction therapies with cyclosporine and tacrolimus monotherapy compared with standard triple therapy as historical control.

METHODS

Patients formed part of the initial cohort in an open-labelled, randomised pilot study and were selected consecutively if they had histological rejection and no other confounding diagnoses. There were 13 patients in the cyclosporine monotherapy group (CsA), 11 in the tacrolimus monotherapy group and 13 in the triple therapy group (CAP). The histology of liver biopsies was reassessed blindly and the severity of rejection was recorded.

RESULTS

The total Royal Free Hospital (RFH) rejection scores as well as other histological features (zone 3 haemorrhage, apoptosis in zones 1 and 3, steatosis, cholestasis, nuclear vacuolation, lymphoblasts and ballooning) were comparable in the three groups. There was no difference in individual components of the histological features comprising the diagnosis of rejection, except that the portal inflammation score was significantly lower in the tacrolimus group when compared with the CsA group (p=0.04). There was no significant difference in the number of patients with moderate/severe rejection between the three groups. Overall, there was no significant increase in histological severity of rejection in the monotherapy groups.

CONCLUSIONS

The results suggest that the monotherapy may be as effective as the triple therapy in the initial post-transplant phase and that no particular graft histological changes were associated with the type of treatment.

The role of different immunosuppression in the long-term histological outcome of HCV reinfection after liver transplantation for HCV cirrhosis

BACKGROUND

The effect of the type of immunosuppression on the course of posttransplant hepatitis C virus (HCV) infection is unclear. The aim of this study was to evaluate the histological outcome of posttransplant HCV infection with respect to initial immunosuppressive therapy in a cohort of 59 of 65 HCV positive transplant patients who survived at least 12 months.

METHODS

Initial immunosuppressive therapy was triple (cyclosporine or tacrolimus and azathioprine and prednisolone) in 41, double (cyclosporine and prednisolone) in 5, and single (cyclosporine or tacrolimus) in 13 patients. There was blinded histological evaluation, based on necroinflammatory activity (grading score:0-18) and fibrosis (staging score: 0-6). The median histological follow-up was 36 (12-72) months.

RESULTS

In the last liver biopsy, high necroinflammatory activity indicating chronic hepatitis (grading score > or =4) was found in 42 (71%) and severe fibrosis or cirrhosis (staging score > or =4) in 18 (30.5%) patients. High necroinflammatory activity was associated significantly with absence of pretransplant alcohol abuse (P=0.01) and relatively with occurrence of posttransplant acute lobular hepatitis C (P=0.055). Development of severe fibrosis or cirrhosis was significantly associated only with the type of initial immunosuppressive therapy. In particular, severe fibrosis or cirrhosis developed significantly more frequently in patients treated with triple or double (17/46 or 37%) than with single initial immunosuppressive therapy (1/13 or 7.7%) (adjusted for biopsy time: P=0.045).

CONCLUSIONS

Severe fibrosis or cirrhosis appears to develop in 30% of HCV transplant patients in a median of 3 years and to be associated with heavier initial immunosuppression.

Murine IL-10 gene transfer inhibits established collagen-induced arthritis and reduces adenovirus-mediated inflammatory responses in mouse liver

The effects of homologous IL-10 administration during an established autoimmune disease are controversial, given its reported immunostimulatory and immunosuppressive properties. Studies of collagen-induced arthritis have shown efficacy with repeated administrations of IL-10; however, when the EBV IL-10 homologue was administered via adenovirus gene transfer technology the results were equivocal. Therefore, the present study was undertaken to elucidate the effects of prolonged homologous IL-10 administration via adenovirus-mediated gene delivery on the progression of established arthritis. Collagen type II (CII)-immunized mice received i.v. injections of 10(7) or 10(8) PFU of an E1-deleted adenoviral vector containing the murine IL-10 gene (AdIL-10), after arthritis onset. Mice were monitored for 3 wk for disease progression, and gene transduction was assessed by quantification of serum mIL-10. CII-specific cell-mediated and humoral immune responses were analyzed by lymph node cell proliferation, cytokine production, and anti-CII Ab responses. Furthermore, because adenoviral vectors have been reported to induce organ dysfunction due to cell-mediated immune responses to the viral Ags, we have also evaluated delayed-type hypersensitivity responses and reactive hepatitis to the systemically delivered adenovirus and whether the IL-10 produced could influence those responses. Sustained suppression of autoimmune arthritis and elevated serum levels of IL-10 were achieved in our study. AdIL-10 treatment reduced cell-mediated immune reactivity, but did not affect humoral responses. Furthermore, IL-10 was able to reduce, but not totally abrogate, adenovirus-induced hepatic inflammation. These findings provide further insights into the diverse interplay of immune processes involved in autoimmune inflammation and the mechanism of cytokine immunotherapy.

The influence of cytomegalovirus viraemia on the outcome of recurrent hepatitis C after liver transplantation

BACKGROUND

Several interrelated host and hepatitis C virus (HCV) associated factors have been proposed to explain the variable outcomes in HCV recurrence. Recent evidence suggests that cytomegalovirus (CMV) infection not only is co-factor in progression of HCV recurrence but may precipitate allograft rejection. We investigated whether short-term CMV viremia influences HCV recurrence, the number and grade of acute rejection episodes, and the histological course of HCV recurrence during the first year after orthotopic liver transplantation (OLT) for HCV-related cirrhosis.

METHODS

A cohort of 39 patients transplanted for cirrhosis HCV-related was analyzed. Patients were evaluated twice weekly for CMV infection by a blood polymerase chain reaction (PCR) assay. Triple therapy with cyclosporine or tacrolimus, azathioprine and prednisolone was the initial immunosuppressive regimen. Preemptive treatment with ganciclovir was started when two consecutive PCRs for CMV were positive. Liver biopsies were performed on day 7 after OLT or when indicated. A 3-day IV 1 g methilprednisolone was given to patients with moderate or severe rejection. Ishak's score was used to grade inflammation and to stage fibrosis.

RESULTS

Neither CMV viremia nor CMV disease after OLT for HCV-related cirrhosis adversely influenced the incidence and grade of acute rejection episodes nor the histological outcome of post transplant HCV recurrence, during the first year after liver transplantation.

CONCLUSION

CMV viremia as detected by PCR does not affect the progression of HCV recurrence in liver grafts.

Development of ductopaenic liver allograft rejection includes a "hepatitic" phase prior to duct loss

BACKGROUND/AIM

Recent reports suggest the possible role of a parenchymal inflammatory reaction in the developing phase of chronic rejection. The aim of this study was to identify both clinical and histological abnormalities related to the development of chronic rejection, especially the topography of the inflammatory reaction occurring in the post-transplant period.

METHODS

We studied retrospectively, 103 liver allograft biopsies from 10 patients. These 10 patients represented all the patients who developed chronic rejection (confirmed by duct loss and foamy arteriopathy in these grafts removed at retransplantation) and who had non-viral-related disease originally; in the study period 1990-1998 at the Royal Free Hospital (during which 451 liver transplants were performed). As a control population, we reviewed 28 patients who had been transplanted for non-viral end-stage liver disease at our institution in the same study period and who were retransplanted for complications other than chronic rejection.

RESULTS

In nine patients documented histologically lobular hepatitis preceded chronic rejection. In one patient, although non-specific lobular changes were present in the early post-transplant period, lobular hepatitis was identified repeatedly after chronic rejection had been diagnosed. Cytomegalovirus was identified immunohistochemically in one patient. In the remaining nine patients extensive clinical and histological investigations failed to demonstrate the presence of any known viral agent. Features of hepatitis were found in only 3 of the 28 patients of the control group.

CONCLUSIONS

A "hepatitic" phase anticipates chronic ductopaenic rejection. Further studies are necessary in order to clarify the pathogenesis of this reaction.

Lamivudine without HBIg for prevention of graft reinfection by hepatitis B: long-term follow-up

BACKGROUND

This open, multicenter study was conducted to evaluate the efficacy and safety of lamivudine prophylaxis given to chronic hepatitis B virus-(HBV) infected patients before and after orthotopic liver transplantation (OLT). We now present long-term data that follow our previous short-term report.

METHODS

Twenty-three patients were treated with lamivudine (100 mg orally, daily); 13 (57%), were serum HBV DNA positive (Abbott Genostics, Abbott Laboratories, Chicago, IL) at study entry. Patients received lamivudine for at least 4 weeks before OLT, and for up to 50 months (median 25 months) after OLT.

RESULTS

Of the 23 treated patients, 17 survived to undergo OLT. Eleven patients (65%) survived up to 4 years (median 36 months) after OLT. One of the survivors stopped lamivudine because of a possible adverse reaction 9 months post-OLT, and prophylaxis with HBV immune globulin was then established. Ten survivors continue lamivudine. Eight long-term survivors have normal liver function without evidence of HBV reinfection. Of the 17 transplanted patients, 6 died. Four patients died (3 days to 5 months post-OLT) without evidence of graft reinfection. Two further patients died at 19 and 23 months post-OLT from graft failure. Both patients had YMDD variant detected at 12 months post-OLT. Two other patients with YMDD-variant HBV remain alive on lamivudine, 9 and 15 months after development of the variant.

CONCLUSIONS

Lamivudine, given before and after OLT, prevents significant graft reinfection for the majority of treated patients. The study has also shown that lamivudine is extremely well tolerated by liver failure patients and for a prolonged period after transplantation.

Hepatitis B virus DNA levels, precore mutations, genotypes and histological activity in chronic hepatitis B

The present study aimed to clarify how viraemia levels reflect the clinical stages of chronic hepatitis B virus (HBV) infection, in particular studying whether 'healthy carriers' can be identified by analysing HBV DNA levels with a highly sensitive quantitative assay. Histology activity index (HAI), alanine aminotransferase (ALT) level, genotype and precore mutations were compared with the HBV DNA level, as measured using the Amplicor HBV Monitor assay in a prospective study. In 124 hepatitis B e antigen-negative (HBeAg-) patients, the majority with mild liver disease, log HBV DNA levels showed a Gaussian distribution around a geometric mean of 33 000 genome copies ml-1, and increasing HBV DNA level was associated with significantly higher inflammation (HAIinfl) and fibrosis (HAIfibr) scores and higher ALTi (ALT / the upper reference value). Severe inflammation (HAIinfl > or = 7) was seen in 83% (five of six), 36% (eight of 22) and 3% (one of 37) of HBeAg- patients with HBV DNA > 107, > 2 x 105 and < 104 copies ml-1, respectively. In severe HBeAg- hepatitis, patients with precore wild-type infection had lower HBV DNA levels than those with precore mutants. In 36 HBeAg-positive (HBeAg+) patients, no correlation between HBV DNA level and liver damage was seen. Ninety-six per cent of HBeAg- patients with ALTi < 0.5 had HAIinfl < or = 3. In HBeAg- carriers with ALTi 0.5-1.0, the relative risk for severe inflammation, comparing HBV DNA > 2 x 105 copies ml-1 vs < 2 x 105 copies ml-1, was 14.7. In conclusion, in HBeAg- carriers, HBV DNA < 104 copies ml-1 or ALTi < 0.5 indicates mild inflammation, while > 2 x 105 copies ml-1 of HBV DNA may justify further investigations. Precore status may be relevant for the interpretation of viraemia.

Beta(beta)3-adrenergic receptors in human pancreatic islet and duodenal somatostatin neuroendocrine cells

BACKGROUND

We previously localized beta3-adrenergic receptors immunohistochemically in human gastrointestinal smooth muscle and incidently found a population of human pancreatic islet cells and duodenal epithelial neuroendocrine cells that also expressed beta3-adrenergic receptors.

AIM

To identify the nature of the islet and duodenal cells that stained positive for beta3-adrenergic receptors.

METHODS

Paraffin sections of human pancreas and duodenum and Chinese hamster ovary cells transfected with the human beta3-adrenergic receptor were immuno-stained for beta3-adrenergic receptors using an affinity-purified rabbit polyclonal antibody (anti-P12) raised against a 15 amino acid sequence (P12) of the human receptor. Immunohistochemical staining for the receptor was carried out in the presence and absence of P12 peptide and both somatostatin 14 and 18 peptides. beta3-adrenergic receptor-stained sections were also double-immunostained with anti-insulin, -glucagon, -somatostatin and -pancreatic polypeptide antibodies.

RESULTS

A subpopulation of human pancreatic islet cells and duodenal epithelial cells expressed positive cytoplasmic beta3-adrenergic receptor immunostaining. Using distribution and double-staining techniques, these cells were found to be somatostatin-positive D cells but not A or B cells. The positive staining of D cells with anti-P12 antibody was inhibited by prior incubation of the antibody with P12 peptide but not somatostatin-14 or -28 peptides. Pancreatic vascular smooth muscle and duodenal vascular and non-vascular smooth muscle also stained with anti-P12 antibody. Transfected Chinese hamster ovary cells showed positive membrane staining.

CONCLUSION

We have identified a population of neuroendocrine cells in the human pancreas and duodenum that express beta3-adrenergic receptors. These cells appear to be somatostatin D cells.

Radioimmunoguided surgery in colorectal cancer using a genetically engineered anti-CEA single-chain Fv antibody

In radioimmunoguided surgery (RIGS), a radiolabeled antibody is given i.v. before surgery and a hand-held gamma-detecting probe is used to locate tumor in the operative field. The rapid blood clearance and good tumor penetration of single-chain Fv antibodies (scFv) offer potential advantages over larger antibody molecules used previously for RIGS. A Phase I clinical trial is reported on RIGS with scFv (MFE-23-his) to carcinoembryonic antigen (CEA). Thirty-four patients undergoing surgery for colorectal carcinoma (17 primary tumors, 16 liver metastases, and 1 anastomotic recurrence) and 1 patient with liver metastases of pancreatic carcinoma received 125I-labeled MFE-23-his scFv (125I-MFE-23-his) 24, 48, 72, or 96 h before operation. 125I-MFE-23-his showed biexponential blood clearance with alpha and beta half-lives of 0.32 and 10.95 h, respectively. The abdomen was scanned during surgery with a hand-held gamma detecting probe (Neoprobe Corp.). 125I-MFE-23-his showed good tumor localization; comparison with histology showed overall accuracy of 84%. Highest median ratios for tumor:normal tissue and tumor:blood were recorded 72 or 96 h after scFv injection for patients undergoing resection of liver metastases. High levels of radioactivity were found in the kidneys. Five patients had grade 1 fever, and three had a grade 1 rise in blood pressure according to the Common Toxicity Criteria. There was a significant correlation between these ratios and those measured in excised tissues using a laboratory gamma counter (P < 0.001). MFE-23-his scFv antibody localizes in CEA-producing carcinomas. The short interval between injection and operation, the lack of significant toxicity, and the relatively simple production in bacteria make MFE-23-his scFv suitable for RIGS.

Similarities between ileal Crohn's disease and indomethacin experimental jejunal ulcers in the rat

BACKGROUND

Both Crohn's disease ileal ulcers and indomethacin-induced jejunal ulcers in the rat have a predilection for the mesenteric margin of the bowel wall. Unlike the anti-mesenteric margin, the mesenteric margin is supplied by small end-arteries that might render it more sensitive to ischaemic injury.

AIM

To examine, in both situations, the histological relationship between the precise localization of small bowel ulcers and the mesenteric margin.

METHODS

Ileal Crohn's disease ulcers identified in surgical resection specimens (n=5) and indomethacin-induced lesions in the rat jejunum (n=6) were examined macroscopically and histologically.

RESULTS

In both the human ileum and the rat jejunum, ulcers occurred consistently along the mesenteric margin, with the most extensive mucosal injury occurring at two adjacent sites on either side of the midline of this margin. At these two sites, feeding arteries entered the muscularis propria.

CONCLUSIONS

For anatomical reasons apparently related to the vasculature of the human and rodent small bowel, specific sites along the mesenteric margin are susceptible to Crohn's disease ulceration and NSAID damage, respectively.

Expression of the mucosal vascular addressin, MAdCAM-1, in inflammatory liver disease

AIMS/BACKGROUND

The integrin alpha4beta7 and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) are involved in normal recirculation of lymphocytes between the blood and the tissues of the gastrointestinal tract. In this study we have examined the expression of MAdCAM-1 in human liver.

METHODS

MAdCAM-1 expression was determined in archival human liver tissues by immunohistochemistry.

RESULTS

While MAdCAM-1 was not detected in normal fetal or adult human liver, expression was observed in association with portal tract inflammation in a variety of liver diseases. Detailed analysis of liver biopsies from patients with hepatitis C showed a positive correlation between the portal/periportal component of the histological activity index (HAI) grade and the presence or absence of MAdCAM-1 expression.

CONCLUSION

MAdCAM-1 expression may be important in the recruitment of lymphocytes to the liver during inflammation.

Genomic heterogeneity in synchronous hepatocellular carcinomas

BACKGROUND

Hepatocellular carcinoma (HCC) arising in cirrhosis is frequently multifocal. Whether HCC develops monoclonally or multiclonally is an unresolved question. Of the multiple tumour nodules present in many patients, it has not been established whether the smaller lesions represent intrahepatic metastases or de novo cancers.

AIMS

To assess the degree of genomic heterogeneity in synchronous HCCs in cirrhosis.

METHODS

The arbitrarily primed polymerase chain reaction technique was utilised to compare the DNA fingerprint of HCCs and regenerative nodules (RNs) removed from cirrhotic explant livers.

RESULTS

Polymorphic genomic heterogeneity was noted in 54 HCCs and 31 RNs microdissected. Even satellite nodules in close proximity within the same segment of the liver were found to have distinct genomic patterns.

CONCLUSION

Such genomic heterogeneity in synchronous HCCs may explain poor patient survival after surgical resection. If the smaller tumours are de novo lesions rather than metastases (as these data suggest), then current concepts regarding liver resection as a curative treatment modality for HCC may require reassessment.

A new variant of GB virus C/hepatitis G virus (GBV-C/HGV) from South Africa

Phylogenetic analysis of the 5' non-coding region (5'NCR) sequences has demonstrated that GB virus C/hepatitis G virus (GBV-C/HGV) can be separated into three major groups that correlate with the geographic origin of the isolate. Sequence analysis of the 5'NCR of 54 GBV-C/HGV isolates from 31 blood donors, 11 haemodialysis patients and 12 patients with chronic liver disease suggests the presence of a new variant of GBV-C/HGV in the province of KwaZulu Natal, South Africa. Eleven isolates grouped as group 1 variants (bootstrap support, 90%) found predominantly in West and Central Africa, a further six isolates grouped as group 2 variants (bootstrap support, 58%) found in Europe and North America; five of which grouped as 2a (bootstrap support, 91%) and one as 2b (bootstrap support, 87%), the latter also includes isolates from Japan, East Africa and Pakistan. Although the remaining 37 GBV-C/HGV isolates were more closely related to group 1 variants (bootstrap support, 90%), they formed a cluster, which was distinct from all other known GBV-C/HGV sequences. None of the South African isolates grouped with group 3 variants described from Southeast Asia. Three variants of GBV-C/HGV exist in KwaZulu Natal: groups 1, 2 and a new variant, which is distinct from other African isolates.

Evolution of genetic abnormalities in hepatocellular carcinomas demonstrated by DNA fingerprinting

Hepatocellular carcinomas (HCC) often contain subpopulations of cells showing heterogeneous differentiation within each tumour. The majority of HCCs first appear as well-differentiated lesions and proliferate with gradual dedifferentiation. The present study was designed to investigate the clonal diversity which is seen with progression in neoplasms. The degree of genomic heterogeneity of HCC nodules was assessed using the arbitrarily primed-polymerase chain reaction technique. Two or more sectors of 31 HCC nodules were needle-microdissected and amplified with two different arbitrary primers in appropriate conditions. In every HCC less than 6 mm in diameter (n=18, range 3-6 mm, mean diameter 4.7 mm), all sectors of each of these lesions had the same DNA fingerprint. All HCC nodules greater than 6 mm diameter (n=13, range 7-30 mm, mean diameter 15.4 mm) showed distinct DNA fingerprints in each sector sampled (p< 0. 05, compared with size less than 6 mm in diameter). When synchronous HCCs were present, no two tumour nodules had the same DNA fingerprint. These results suggest that a process of clonal evolution occurs in expanding HCC, with neoplasms more than 6 mm in diameter developing as multiple clones. The advent of laser capture microdissection technology makes such analysis much more rapid and easily applied. Studies of clonality in HCCs, including borderline cases, are made possible by the combination of these novel techniques.

Demonstration of new sites of expression of the CCK-B/gastrin receptor in pancreatic acinar AR42J cells using immunoelectron microscopy

The CCK-B/gastrin receptor has been characterised in both normal and tumour tissues. Endocytosis of the CCK-B/gastrin receptor has recently been demonstrated and this has similarly been described for other peptide receptors. In addition, ligand and ligand-receptor translocation to the nucleus has been demonstrated for other peptides. The aim of this study was to identify the sites of expression of the CCK-B/gastrin receptor in the known CCK-B/gastrin receptor bearing pancreatic acinar AR42J cells. The specificity of the CCK-B/gastrin receptor antibody (alpha-CCKBR-Ser antibody) was demonstrated by inhibition ELISA studies, radioligand inhibition studies and immunofluorescence binding studies on AR42J cells. Western blotting and immunogold electron microscopy techniques were used to identify the receptor in AR42J cell preparations. The affinity purified alpha-CCKBR-Ser antibody was shown to be specific for the CCK-B/gastrin receptor. The receptor was expressed on the cell membrane, in the cytoplasm and within the nucleus. Isoforms of the receptor protein identified in extra-nuclear and nuclear extracts ranged in molecular weight from 58 to 66 kDa. We conclude that the CCK-B/gastrin receptor is not only expressed on the cell membrane, but also in the cytoplasm and nucleus of AR42J pancreatic acinar cells.

Longitudinal variation in hepatitis C virus (HCV) viraemia and early course of HCV infection after liver transplantation for HCV cirrhosis: the role of different immunosuppressive regimens

BACKGROUND

The role of the type of immunosuppression in the natural history of post-transplant hepatitis C virus (HCV) infection is unclear.

AIMS

To evaluate the fluctuation of HCV viraemia and the early course of infection, and their relation to the type of immunosuppression in HCV transplant patients.

METHODS

In 47 HCV transplant patients, serum HCV RNA levels were determined pretransplant and at one and two weeks, and three and 12 months after transplant. Initial immunosuppression was triple (cyclosporin, azathioprine, prednisolone) in 31, double (cyclosporin, prednisolone) in five, and single (cyclosporin or tacrolimus) in 11 patients. Prednisolone was withdrawn at a median of six months.

RESULTS

At three months, HCV RNA levels were higher in patients with single than with triple or double initial therapy. At 12 months, HCV RNA levels correlated only with duration of prednisolone treatment and were relatively higher in patients with triple compared with single initial immunosuppression. A higher necroinflammatory activity at 12 months post-transplant was found in patients with post-transplant acute hepatitis compared with those without. Extent of fibrosis at 12 months was associated with the 12 month HCV RNA level and occurrence of post-transplant acute hepatitis.

CONCLUSIONS

HCV RNA levels at three months after transplant are higher in patients treated with single initial immunosuppressive therapy, but at 12 months are higher in patients with longer duration of steroid treatment. HCV viraemia at 12 months seems to be particularly important, as its levels are strongly correlated with the severity of fibrosis.

HBeAg immunostaining of liver tissue in various stages of chronic hepatitis B

AIMS

We studied the tissue expression of hepatitis B e antigen (HBeAg) in 29 liver biopsies from 27 HBV carriers.

METHODS

HBeAg expression was assessed in relation to HBeAg in serum, precore mutations, HBV DNA levels and liver damage as measured by histology activity index.

RESULTS

HBeAg in liver tissue was detected by immunostaining in 6 of 7 patients positive for HBeAg in serum. In patients negative for HBeAg in serum, HBeAg was detected in none of 11 specimens from patients infected exclusively with a precore mutant that disrupts HBeAg synthesis, as compared with 3 of 11 specimens from patients carrying HBV with an intact precore region. These 3 patients all showed high HBV DNA levels in serum and severe liver damage.

CONCLUSIONS

Overall, viral replication was strongly associated with the cytoplasmic HBeAg and nuclear HBcAg staining, but not with tissue staining for HBsAg. Because of the close relationship between tissue HBeAg expression and high viral load, the pathogenetic importance of HBeAg remains unclear.

Interobserver study of liver histopathology using the Ishak score in patients with chronic hepatitis C virus infection

AIMS/BACKGROUND

Assessing the histopathological degree of liver damage is essential to the routine care of patients with chronic hepatitis C virus (HCV) infection. Several scoring systems have been proposed in attempts to standardize the histological assessment. One scoring system has been proposed by Ishak et al. Although widely endorsed, its interobserver reliability has not been evaluated.

METHODS

95 liver biopsies from patients with chronic HCV infection were scored by three independent observers. Interface hepatitis, confluent necrosis, focal necrosis, portal inflammation, and fibrosis were assessed.

RESULTS

Confluent necrosis, which is more common in acute hepatitis, was not seen in any biopsy. For each of the remaining variables of inflammation (periportal hepatitis, focal necrosis, and portal inflammation) we found agreement in 95-96% for all three observers. Kappa scores ranged from 0.11 to 0.41 and weighted kappa scores from 0.18 to 0.53. For staging we noted 84% agreement, kappa scores of 0.26-0.47, and weighted kappa scores of 0.57-0.69.

CONCLUSION

The Ishak system is associated with good interobserver reliability if a deviance of one categorical level in each variable of the system is accepted as agreement. Compared to the Knodell system it provides more detailed information but is less reliable regarding fibrosis.