Low serum levels of CD44, CD44v6, and neopterin indicate immune dysfunction in chronic pancreatitis

INTRODUCTION: In autoimmune diseases, malignancies, and inflammatory conditions, a correlation of serum levels of CD44, interleukin-2 receptor (IL-2r), and neopterin with disease activity could be shown. AIMS: To assess the immune parameters in chronic pancreatitis in correlation to clinical data to evaluate the potential role of immune dysfunction as a risk factor. METHODOLOGY: Levels of IL-2r, sCD44, sCD44v6, and neopterin were measured using the enzyme-linked immunosorbent assay in 63 patients with chronic pancreatitis who underwent surgery between 1992 and 1995 in our institution. Clinical data were evaluated prospectively before surgery, and a follow-up investigation was conducted in 1997. RESULTS: Mean serum levels of CD44, CD44v6, and neopterin were significantly lower in patients with chronic pancreatitis compared with the control group. The mean level of IL-2r was also lower in chronic pancreatitis, but this difference was not significant. However, no influence of immunosuppressive factors such as alcohol consumption, cigarette smoking, or diabetes could be detected on the levels of IL-2r, CD44, CD44v6, and neopterin. CONCLUSION: In accordance with other diseases of reduced immunoreactivity, depressed serum levels of biomarkers in chronic pancreatitis are caused by reduced T-lymphocyte and macrophage activation. By ruling out a significant influence of concomitant immunosuppressive factors, we conclude that the inflammatory process itself is the source of the depressed immune function, which might be restored by surgical resection.     

Elevated serum neopterin levels in sarcoidosis

Neopterin levels have been reported elevated in diseases with changed cellular immune response. The study reported here was designed to examine whether serum neopterin (S-neopterin) could be a marker of activity in sarcoidosis. S-neopterin was measured by radioimmunoassay in 37 patients with inactive and 34 patients with active sarcoidosis and in 38 controls. The levels were significantly elevated in both sarcoid groups and increased in stage III compared to I and II. S-neopterin levels were significantly correlated to levels of serum angiotensin-converting enzyme (SACE) and immunoglobulins IgG and IgA. The results indicate that S-neopterin may be a marker of activity in sarcoidosis.     

Helicobacter pylori Stool Antigen test: a reliable non-invasive test for the diagnosis of Helicobacter pylori infection in children

OBJECTIVE: To evaluate the Helicobacter pylori Stool Antigen (HpSA) test for the diagnosis of H. pylori infection in children. DESIGN AND SETTING: Prospective cohort study in an academic medical centre. PATIENTS AND METHODS: A total of 106 consecutive children who underwent gastroscopy were included. Biopsy specimens were sampled from the gastric antrum and corpus for the assessment of H. pylori infection by culture and histology. A patient was defined to be H. pylori positive if the results of culture and/or histology proved to be H. pylori positive; a patient was defined to be negative if both test results were negative. All children provided a stool sample within 2 days of gastroscopy. H. pylori antigens in faeces were assessed by an enzyme immunoassay (Premier HpSA, Meridian Diagnostics, Inc., Cincinnati, OH, USA). RESULTS: The mean age of included patients was 8.5 years (range 1-18.5). Thirty patients were H. pylori positive and 76 patients were H. pylori negative. Using the recommended cut-off values of 0.140 optical density (OD) and 0.159 OD, sensitivity and specificity of 100% and 92% were found. The positive and negative predicting values were 83% (30/36) and 100% (70/70), respectively. CONCLUSION: The HpSA test is an accurate test for the diagnosis of H. pylori infection in children, and might therefore be a good alternative for diagnostic tests such as the 13C-urea breath test (UBT).     

Urinary neopterin levels in acute viral hepatitis

Elevated neopterin levels in blood or urine have been shown to be a marker for the activation of cell-mediated immunity in vitro and in vivo. To evaluate whether neopterin levels are elevated in patients with acute viral hepatitis, we measured urinary levels in 13 patients with hepatitis A, 26 with hepatitis B, 12 with non-A, non-B hepatitis, 8 with jaundice and/or cholestasis due to biliary and pancreatic disorders and 3 with alcoholic hepatitis and in 62 apparently healthy HBsAg carriers. Neopterin levels in patients with virus-induced hepatitis were significantly higher than those in patients with other diagnoses. Urinary neopterin levels were above normal in 49 of 51 patients with viral hepatitis and elevations during the course of hepatitis showed a pattern similar to that of the usual liver biochemical tests, suggesting that neopterin levels were related to the clinical activity of the viral disease. In patients with nonviral biliary and hepatic disorders, neopterin levels were usually normal and did not correlate with other liver biochemical tests. These findings suggest that cell-mediated immune mechanisms are activated during viral hepatitis and that neopterin measurement may be of value as an additional surrogate marker for non-A, non-B hepatitis.     

Radioimmunological determination of neopterin in blood donors

In 518 sera from blood donors below 30 years of age Neopterin was determined by radioimmunoassay. 21 of these patients (= 4.05%) showed elevated serum levels for Neopterin. By clinical investigation of these cases viral infections of the upper airways were found. Furthermore after elimination of elevated values significant differences in normal Neopterin serum levels could be demonstrated for female and male blood donors (p less than 0.01). Because elevated Neopterin serum levels indicate immune responses to several antigens, determination of Neopterin from serum may be useful for detection of infectious blood samples.     

Elevated levels of neopterin in sleep-disordered breathing

BACKGROUND: Sleep-disordered breathing (SDB) is increasingly being recognized as an independent risk factor for hypertension and cardiovascular disease. Recent evidence suggests that the maladaptive physiologic response to SDB, particularly cardiovascular effects, may result in part from systemic inflammation. Although abnormal cytokine levels have been documented in SDB, data on whether SDB is associated with cellular activation are limited. Thus, this investigation sought to determine whether neopterin, a marker released by activated macrophages, is increased in SDB. METHODS AND RESULTS: Fifty-five men, free of medical comorbidity, undergoing polysomnography had fasting serum tested for neopterin levels. Multivariable regression methods were used to quantify the association between neopterin and quartiles of the apnea hypopnea index (AHI) while accounting for body mass index, waist circumference, and percentage of body fat. Quartiles of AHI (I: < 3.83 events per hour; II: 3.83 to 11.98 events per hour; III: 11.99 to 36.82 events per hour; IV > 36.82 events per hour) indicated a range from no SDB through severe SDB. Compared to the subjects in the first AHI quartile, serum neopterin levels were higher by 3.0%, 10.9%, and 26.5% in the second, third, and fourth AHI quartiles, respectively (p < 0.001for linear trend). Neopterin levels also were higher in those with greater degree of sleep-related hypoxemia, more stage 1 sleep, and less stage 2 sleep. CONCLUSION: The results of this study indicate that severity of SDB independently associates with serum levels of neopterin, a marker for macrophage activation that may play an important role in the pathogenesis of SDB-related cardiovascular disease.     

Elevated serum neopterin levels in atherosclerosis.

Plasma levels of neopterin were determined in patients with different clinical stages of atherosclerosis. Non-hospitalized patients with atherosclerosis had serum and plasma neopterin levels within the normal range of the assay (6 +/- 2 nM). These values were not significantly different from those reported for healthy blood donors (5 +/- 2 nM). In contrast, about 50% (29 out of 61) of hospitalized patients undergoing conservative or surgical therapy had neopterin plasma levels, which exceeded the normal range (greater than 10 nM) up to 10-fold. The two groups differ on a significance level of P less than 0.01. For further evaluation hospitalized patients were subgrouped according to neopterin levels. In the subgroup with elevated neopterin levels patients with higher Frederickson types of atherosclerosis were overrepresented compared to patients with normal neopterin levels. Type 4 differed significantly from patients without pathological changes of lipoprotein (P less than 0.05). Only 3 patients suffered from minimal skin necrosis, two of them had elevated neopterin levels. Significantly more patients with peripheral artery occlusions had elevated neopterin levels than patients with occlusions of central arteries (P less than 0.05). All other criteria used for comparison (sex, age, smoking, antioxidant status, diabetes, hypertension, adipositas, hyperuricemia) did not vary significantly in both subgroups. These data indicate that neopterin plasma levels might be a valuable parameter in activity staging and therapeutic follow up of atherosclerotic patients. Additionally, an involvement of the nonspecific immune system in atherogenesis is suggested by the increased plasma neopterin concentrations.     

New combination test for hepatitis C virus genotype and viral load determination using Amplicor GT HCV MONITOR test v2.0

AIM: To develop a new sensitive and inexpensive hepatitis C virus (HCV) combination test (HCV Guideline test) that enables the determination of HCV genotypes 1, 2 and 3, and simultaneous determination of HCV viral load using commercial Amplicor GT HOV MONITOR test v2.0 (microwell version). METHODS: The HCV Guideline test used the PCR product generated in commercial Amplicor GT HCV Monitor test v2.0 for viral load measurement using microwell plate version of Amplicor HCV Monitor and also captured on separate plates containing capture probes and competitive oligonucleotide probes specific for HCV genotypes 1, 2 and 3, The HCV genotype was subsequently determined using the biotin-labeled PCR product and five biotin-labeled HCV-specific probes. RESULTS: The sensitivity of the HCV Guideline test was 0.5 KIU/mL. Specificity of the HCV Guideline test was confirmed by direct sequencing of HCV core region and molecular evolutionary analyses based on a panel of 31 samples. The comparison of the HCV Guideline test and an in-house HCV core genotyping assay using 252 samples from chronic hepatitis C patients indicated concordant results for 97.2% of samples (59.5% genotype 1, 33.7% genotype 2, 6.0% genotype 3, and 0.8% mixed genotypes). Similarly, the HCV Guideline test showed concordance with a serological test, and the serological test failed to assign any serotype in 12.7% of the samples, indicating a better sensitivity of the HCV Guideline test. CONCLUSION: Clinically, both viral load and genotypes (1, 2 and 3) have been found to be major predictors of antiviral therapy outcome regarding chronic hepatitis C based on guidelines and they are, in normal circumstances, performed as separate stand-alone assays. The HCV Guideline test is a useful method for screening large cohorts in a routine clinical setting for determining the treatment regimen and for predicting the outcome of antiviral therapy of chronic hepatitis C.     

Serum neopterin concentrations in chronic liver disease.

Neopterin is produced by macrophages after stimulation with interferon gamma or lipopolysaccharide. Its production is increased in many infectious, autoimmune, and malignant diseases. The aim of this study was to examine whether, on the basis of neopterin as a marker, liver diseases could be classified according to aetiology and stage of disease. A cohort of 264 patients with chronic liver diseases (viral, metabolic, autoimmune, toxic) and 150 normal controls were studied; 136 of the patients had cirrhosis. Increased serum neopterin concentrations were found in 41% of all patients (controls 6.0 (2.2) nmol/l), with patients in the cirrhotic stage of disease showing higher neopterin values (mean (SD) 15.7 (23.6) nmol/ml) than those in the non-cirrhotic stage (9.9 (5.5)). There were no statistically significant differences in the serum neopterin concentrations that could be considered characteristic for different stages of disease classified according to the Child criteria. Such differences in concentrations of neopterin that were found in patients with liver diseases grouped according to underlying causes were only marginal. Serum neopterin concentrations were found to be significantly lower than in any other disease group only in patients with Wilson''s disease. The results suggest that activated macrophages participate in the development of chronic liver disease. Measurement of serum neopterin does not offer a reliable method for differentiating between various aetiologies of chronic liver diseases and does not help to predict severity of cirrhosis.     

A T‐cell diagnostic test for cystic echinococcosis based on Antigen B peptides

Cystic echinococcosis (CE) immunodiagnosis is still imperfect. We recently set‐up a whole‐blood test based on the interleukin (IL)‐4 response to the native Antigen B (AgB) of Echinococcus granulosus. However, AgB is encoded by a multigene family coding for five putative subunits. Therefore, the aims of this study were to analyse the IL‐4 response to peptides spanning the immunodominant regions of the five AgB subunits and to evaluate the accuracy of this assay for CE diagnosis. Peptides corresponding to each subunit were combined into five pools. A pool containing all peptides was also used (total pool). IL‐4 evaluated by enzyme‐linked immunosorbent assay was significantly higher in patients with CE compared to those without (NO‐CE subjects) when whole‐blood was stimulated with AgB1 and with the total pool. Moreover, IL‐4 levels in response to the total pool were significantly increased in patients with active cysts. Receiver Operator Curve analysis identified a cut‐off point of 0.59 pg/mL predicting active cysts diagnosis with 71% sensitivity and 82% specificity in serology‐positive CE patients. These data, if confirmed in a larger cohort, offer the opportunity to develop new diagnostic tools for CE based on a standardized source of AgB as the peptides.     

Serum neopterin and activity of coronary artery disease

Inflammation plays a key role in the pathogenesis of atherosclerosis. In coronary artery disease (CAD), the release of different cytokines activates cellular defense. Infiltration of neutrophils and monocytes/macrophages is detected in the vessel wall in patients with CAD. Macrophages activated by interferon gamma synthesize metalloproteinases and neopterin, a pteridin derivative that has been used as an immune marker. To determine neopterin levels in patients with chronic CAD and acute coronary syndromes, the authors studied 116 subjects: 1) 25 consecutive patients (18 men, 7 women; mean age 68.5 +/- 14.3, range 40 to 86 years) with unstable angina or acute myocardial infarction (AMI); 2) 31 consecutive patients (25 men, 6 women; mean age 64 +/- 12.7, range 47 to 83 years) with signs and symptoms of clinically stable CAD; and 3) 60 consecutive healthy blood donors (38 men, 22 women; mean age 54.4 +/- 6.23, range 44 to 66 years). Neopterin levels were determined with a commercially available enzyme-linked immunosorbent assay method. In patients with unstable angina and AMI before thrombolytic therapy, neopterin levels were not significantly different from levels in patients with stable CAD (5.97 +/- 1.4 versus 7.84 +/- 3.56 nmol/L; P = 0.15). Neopterin levels in both patient groups did not significantly differ from levels in control subjects (P > 0.1). Neopterin levels in patients with unstable angina and AMI were measured four times during a 72-hour period. The lowest value was observed at baseline and differed significantly from values after 72 hours (P < 0.001; 5.97 +/- 1.4 versus 9.25 +/- 2.36). Neopterin levels after 72 hours were also significantly different from initial values in patients with stable CAD (P < 0.001). There was no correlation between neopterin and creatine kinase (CK) levels, CK-MB isoenzyme, or troponin I as markers for the extent of the myocardial injury during the observation period. These data do not support previous reports of higher baseline levels of serum neopterin in patients with unstable angina or AMI compared with patients with chronic, stable CAD and healthy controls. Neopterin as a marker of macrophage activation is significantly increased in patients with AMI and unstable angina shortly after the onset of symptoms (after a period of 72 hours), supporting the hypothesis of monocyte and macrophage activation in patients with an acute coronary syndrome or AMI.     

Adenosine deaminase isoenzymes and neopterin in liver cirrhosis

The aim of this study was to define the pattern of neopterin and ADA isoenzymes in liver cirrhosis. A total of 117 patients with liver cirrhosis were included. Serum levels of ADA were assayed in the presence and absence of a specific inhibitor for ADA1. Serum neopterin was measured using a competitive enzyme-linked immunosorbent assay. The grade of liver insufficiency was assessed according to the Child-Pugh classification and the monoethylglycinexylidide test. Serum ADA, ADA1, ADA2 and neopterin were higher in cirrhotic patients than in control subjects. A stepwise increase in serum ADA level was observed with increasing severity of liver cirrhosis. The probability of ADA2 being greater than the mean was approximately 2.5 times higher (2.48, CI 95%: 1.36-4.52) in patients with liver cirrhosis due to hepatitis C virus (HCV) infection than in those patients with cirrhosis of a different etiology. No correlation was found between ADA2 and neopterin. Our data show that liver insufficiency and HCV infection increase the serum levels of ADA and its major isoenzyme ADA2. Furthermore, ADA isoenzyme determination adds no value to total ADA value. The absence of a correlation between ADA2 and neopterin suggests that different physiologic processes are involved in their increase.     

Serum neopterin levels in patients with non-alcoholic steatohepatitis

Aim:  Neopterin is a marker of cell-mediated immunity. It also has a fundamental role in host-defense reactions, including interactions with reactive oxygen intermediates and the promotion of local and systemic oxidative stress. The present study aimed to assess the importance of serum neopterin levels in patients with non-alcoholic steatohepatitis (NASH).
Methods:  Thirty-nine patients with NASH diagnosed by liver biopsy and 32 healthy adults (controls) were enrolled in the study. Serum neopterin levels were measured with an enzyme-linked immunosorbent assay in addition to other biochemical parameters, including liver enzymes. Histopathological examinations were graded as suggested by both the necroinflammatory activity grading system and the NASH scoring system.
Results:  The mean serum neopterin levels were higher in patients with NASH compared to the controls (24.1 ± 16.4 vs 16.2 ± 9.5, P  = 0.019). The histological examination of liver biopsies revealed that 34 of the patients with NASH had grade 1 steatohepatitis and only five patients had grade 2 steatohepatitis. A higher serum mean neopterin level was detected in grade 2 patients compared to grade 1 (40.6 ± 5.6 vs 21.7 ± 16.1, P  = 0.014). A gradual increase was also observed in serum neopterin levels with the increase of the NASH score.
Conclusion:  The serum neopterin levels were significantly higher in patients with NASH compared to the controls, and levels showed an association with the severity of liver damage.     

Urinary neopterin index as a measure of rheumatoid activity

The urinary neopterin index (U-NEOPT-I), expressed as micro-moles of neopterin/moles of creatinine) of 67 patients with definite or classical rheumatoid arthritis was significantly higher than that of sex- and age-matched persons or of 24 non-matched patients suffering from osteoarthrosis or arthralgia (2p less than 0.001). Furthermore, the patients with active disease had statistically significantly increased U-NEOPT-I when compared with patients with a clinically less active disease. In this study, the U-NEOPT-I value was the equal of CRP as a measure of rheumatoid activity. We suggest that neopterin might be involved in the pathogenesis of rheumatoid arthritis.     

Serum neopterin levels in patients with chronic hepatitis B

The aim of this study was to determine the neopterin levels and peripheral blood lymphocyte subgroups in HBeAg-positive and -negative chronic hepatitis B patients. A total of 89 patients were included in the study. The mean serum neopterin level of patients with chronic hepatitis B was significantly higher than that of the control group. In HBeAg-positive chronic hepatitis B patients, the mean serum neopterin level was significantly higher than that of anti-HBeAb-positive patients. There was no significant correlation between the serum neopterin levels and alanine aminotransferase and HBV-DNA levels in HBeAg-positive chronic hepatitis B patients. There were no significant differences between the control subjects and patients with HBeAg-positive or anti-HBeAb-positive hepatitis in terms of the percentage of peripheral blood CD4+ or CD8+ or the ratio of CD4+/CD8+ lymphocytes. Our results suggest an association between elevated neopterin concentrations and HBeAg-positivity in patients with chronic hepatitis B. However, there appears to be no association between the neopterin levels and either hepatocyte damage or viral replication status.