In vivo and in vitro modulation of immune stimulatory capacity of primary dendritic cells by adenovirus-mediated gene transduction.

Dendritic cells (DCs) are potent antigen-presenting cells which are key leukocytes in the initiation of cell-mediated organ graft rejection, antiviral immunity, and antitumor responses. In this study we demonstrate that genetic modification of primary human and mouse DCs by adenoviral gene transfer is an effective means of induction and modulation of antigen presentation by DCs. An adenovirus vector (AdLacZ) was used to express an intracellular model antigen beta-galactosidase (beta-gal) in DCs. Our results show that 30-40% of precursor dendritic cells (PDCs) derived from human umbilical cord blood and circulating mature blood DCs express high levels beta-galactosidase (beta-gal) after infection with AdLacZ with no cytopathic effect observed. In vitro, AdLacZ transduced PDCs and DCs demonstrated a 10- to 20-fold higher mixed lymphocyte reaction (MLR) stimulatory capacity as compared to that of monocytes. In vivo, immunization with AdLacZ transduced mouse DCs resulted in more potent cytotoxic T lymphocyte (CTL) responses against the predicted H-2 restricted beta-gal epitope as compared to CTL responses obtained by beta-gal peptide pulsed DCs. Modulations of the MLR stimulatory capacity of DCs were examined by expression of mouse B7 and CTLA-4Ig. The results show that expression of mouse B7 by a recombinant adenoviral vector (Ad7) significantly enhances the MLR stimulatory capacity of human DCs. In contrast, expression of CTLA-4Ig (AdCTLA-4Ig) reduces the MLR stimulatory capacity of the transduced cells. We conclude that recombinant adenovirus can readily be used for genetic modulation DC-induced immune responses in vivo and in vitro. DCs targeted for induction of specific antigen responses or for modulation of the immune stimulatory capacity may have a potential use in the control of transplantation rejection or viral infections.

Detection of hepatitis C viraemia in Caucasian patients with hepatocellular carcinoma.

Potential risk factors for the development of hepatocellular carcinoma were analysed in 40 Caucasian patients with this malignancy. A higher proportion (14 of 40; 35%) had evidence of hepatitis C virus (HCV) infection than had evidence of either hepatitis B virus (HBV) carriage (17.5%) or alcohol abuse (30%). In all 14 patients whose sera were reactive by HCV ELISA (Ortho second generation test), the presence of antibodies to HCV were confirmed by recombinant immunoblot assay (Ortho RIBA-2). Furthermore, two independent laboratories detected HCV-RNA in 10 of the 14 (71%) anti-HCV positive sera. Two additional sera were shown to contain HCV-RNA when reanalysed by a modified PCR using oligonucleotide primers designed to amplify a shorter fragment of the 5' noncoding region of the genome. Seven of the anti-HCV positive patients also had evidence of prior HBV infection and 2 admitted to alcohol abuse. HCV infection was the only identifiable risk factor in 6 patients. These data confirm the association between HCV infection and hepatocellular carcinoma and suggest that persistent viral replication accompanies tumour development in the majority of patients whose serum contains anti-HCV.

Evolution and regression of pancreatic calcification in chronic pancreatitis. A prospective long-term study of 107 patients.

Pancreatic calcifications are virtually pathognomonic of chronic pancreatitis and develop in up to 90% of patients with alcoholic chronic pancreatitis in series with long-term results. We investigated the natural course of pancreatic calcification in a prospective longitudinal study over the past 23 yr. All patients were studied at regular intervals with particular regard to etiology, clinical findings, surgery, pancreatic function, and pancreatic calcification visible by x-ray (e.g., film series in three projections centered on the pancreas). We evaluated the findings of 107 patients with x-ray documentation of pancreatic calcification in at least three film series over a period of 4 yr or longer. Eighty-four patients had alcoholic chronic pancreatitis (group A) and 23 patients had nonalcoholic chronic pancreatitis (group B). Four hundred seventy-two film series of group A and one hundred forty-two film series of group B were reviewed independently by two expert teams. Both series were graded according to a score system in terms of intensity and distribution of pancreatic calcification (correlation of grading r = 0.91). The duration of calcification averaged 10 yr in group A and 12.6 yr in group B. Similar dynamic changes of pancreatic calcification were noted in groups A and B. Chronologically, three phases of evolution could be distinguished. After an initial increase (phase 1), greater than 50% of cases reached a plateau of stationary calcification (phase 2). Approximately one-third of cases showed a marked decrease of calcification in late phases of chronic pancreatitis (phase 3). Dissolution of pancreatic stones was related primarily to duration of chronic pancreatitis (duration of calcification and marked pancreatic dysfunction), and occurred frequently (but not exclusively) in patients after ductal drainage procedures. These results indicate that spontaneous dissolution of pancreatic stones is a rather common biologic phenomenon. The factors responsible for dissolution of stones remain to be elucidated.

Differences in the natural history of idiopathic (nonalcoholic) and alcoholic chronic pancreatitis. A comparative long-term study of 287 patients.

Controversies in the literature regarding definition, diagnosis, and therapy of chronic pancreatitis may be related in part to differences in the natural history of alcoholic and idiopathic (nonalcoholic) chronic pancreatitis. In order to evaluate this problem the long-term course of 205 patients with alcoholic (85.4% with calcifications) (group A) and 82 patients with idiopathic (nonalcoholic) chronic pancreatitis (76.8% with calcifications) (group B) has been analyzed prospectively since 1963. The patients were studied at regular intervals with particular regard to pain, pancreatic exocrine, and endocrine function and calcifications. The observation time was 2 years or longer in 230 patients with a median observation time of 6.7 years from diagnosis in group A and 10.6 years in group B. In group B over 50% of the cases had primary painless chronic pancreatitis. Progressive deterioration of exocrine and endocrine function was observed in both groups. However, in group A the rate of progression of exocrine dysfunction after diagnosis was more rapid and the incidence of diabetes in relation to marked exocrine insufficiency was much higher than in group B. Steatorrhea preceded diabetes in 56% (group A) and 80% (group B), respectively. Onset of pancreatic calcifications was closely associated with pancreatic exocrine insufficiency in group A in contrast to group B. In addition lasting pain relief occurred spontaneously in about 30% of patients in group B despite a normal exocrine function for 6 years or longer which is in disaccord with the results in alcoholic chronic pancreatitis. In conclusion group A and B have many features in common, in particular the high incidence of pancreatic calcifications and the progressive pancreatic dysfunction. However, the long-term profile of both groups differs in some important aspects, particularly in the clinical pattern and in the rate of progression of pancreatic dysfunction and morphology. These differences should be appreciated in the discussion of problems regarding definition, diagnosis, and surgical therapy of chronic pancreatitis.

Lipasuria in acute pancreatitis: result of tubular dysfunction?

Lipase, in contrast to amylase, is completely reabsorbed by the proximal tubules after glomerular filtration. Therefore, no lipase is detectable in the unconcentrated urine according to the current opinion. The handling of lipase (detected with an enzyme-immunoassay) by the kidney was investigated in comparison with creatinine, amylase, and beta-2-microglobulin by clearance studies in acute pancreatitis (n = 10), burn injury (n = 4), glomerular proteinuria (n = 8), and controls without evidence of pancreatic or renal diseases (n = 5). In initial stages of acute pancreatitis a measurable clearance of lipase (mean: 49.6 microliters/min, range: 0.5-234) was found in association with corresponding increased clearances of beta-2-microglobulin (mean: 10.5 ml/min, range: 0.02-58.9) and of amylase (mean: 8.9 ml/min, range: 2.4-22.6) in nine of ten patients. This finding is consistent with a defect of tubular function. However, regression analysis failed to show a significant correlation between lipase and beta-2-microglobulin clearance. Repeated measurements during the course of pancreatitis in seven patients showed reversibility of tubular dysfunction. In patients with burn injury a similar elevation of clearances of beta-2-microglobulin and of amylase was found, but tubular dysfunction in this condition was not associated with lipasuria. In glomerular proteinuria a lipase clearance was found in two of five cases with moderate, and in the other three cases with severe impairment of creatinine clearance. beta-2-microglobulin clearance was normal in the former and only slightly elevated in the latter group. In conclusion lipase is measurable in the urine of most patients with acute pancreatitis as a result of a reversible tubular dysfunction.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute (nonprogressive) alcoholic pancreatitis: prospective longitudinal study of 144 patients with recurrent alcoholic pancreatitis.

Over the last 10 years, a series of 144 consecutive patients with alcoholic recurrent pancreatitis have been studied prospectively at regular intervals with particular regard to exocrine function, calcifications, pancreatographic ductal changes, and histopathology of the pancreas. Based upon the long-term course, the patients were classified into two groups; group A (n = 95), those with chronic pancreatitis (78 of them with calcifications); and group B (n = 49), those with acute (nonprogressive) pancreatitis. The duration of disease from onset was 2-19 years (median, 9.7 and 8.3 years, respectively, in group A and B). The two groups were comparable at onset of the disease in age, sex, number of episodes of pancreatitis, and number of pseudocysts. In group A, all 95 cases fulfilled the strict diagnostic criteria of chronic pancreatitis within the period of observation (e.g., progressive exocrine insufficiency and/or typical morphological changes, particularly calcifications). In group B, the exocrine function remained normal over the entire period of observation. No histologic evidence of chronic pancreatitis was detected in five of seven large pancreatic specimens. Marked to moderate ductal changes were found in 10 of 16 patients in group B (despite normal exocrine function). Our data suggest that about one third of patients of the present series with alcoholic (recurrent) pancreatitis did not progress toward chronic (progressive) pancreatitis, although some demonstrated morphological alterations (except calcifications) in association with normally preserved exocrine function (residual scars?). The pathogenetic factor(s) responsible for progression (or nonprogression) of alcoholic (recurrent) pancreatitis to chronic pancreatitis remain(s) to be elucidated.

Cholestasis in alcoholic chronic pancreatitis. Diagnostic value of the transaminase ratio for differentiation between extra- and intra-hepatic cholestasis.

In our long-term study of alcoholic chronic pancreatitis (median follow-up time, 10.4 years) 84 of 173 patients (48.6%) developed transient or persistent cholestasis with or without hyperbilirubinemia. We studied the discriminative value of the ASAT/ALAT ratio to differentiate intrahepatic (IHC) and extrahepatic cholestasis (EHC; due to stenosis of the distal common bile duct) in 75 of these patients. In 45 patients with persistent or recurrent cholestasis (group A) the cause of cholestasis was documented by accurate morphological methods. Thirty of the other 39 patients with transient cholestasis (group B) were classified on the basis of the overall clinical evaluation. Of 37 patients with IHC 36 had an ASAT/ALAT ratio of 1.5 or higher (one patient had normal values for both transaminases). Out of 38 patients classified as EHC 29 had an ASAT/ALAT ratio of 1.4 or lower (9 with normal transaminases being excluded). One patient with cholangitis secondary to EHC had a transient elevation of the ASAT/ALAT ratio to above 2.5. Thus our data suggest that in alcoholic chronic pancreatitis associated with cholestasis an ASAT/ALAT ratio of 1.4 or lower (or normal transaminases) usually indicates EHC. Diagnostic study and surgical decompression is mandatory in these cases if EHC persists.