Friedrich Kueppers

Comparison of a Salivary/Sputum Pepsin Assay with 24-Hour Esophageal pH Monitoring for Detection of Gastric Reflux into the Proximal Esophagus, Oropharynx, and Lung

The purpose of this study was to determine whether measurement of salivary/sputum pepsin could be used as a surrogate marker for detecting gastroesophageal reflux using 24-hr esophageal pH monitoring as the gold standard. Patients with gastroesophageal reflux symptoms underwent simultaneous 24-hr esophageal pH monitoring and collection of saliva and sputum samples for pepsin measurement using a recently developed assay. In all, 16 patients provided 19 positive (10.6%) and 161 negative pepsin assays. The mean pH values for the positive pepsin samples were lower then the negative samples at both the proximal [5.34 (95% CI, 4.94–5.75) vs 6.12 (95% CI, 6.03–6.20; P <0.01)] and distal [4.97 (95% CI, 4.61–5.33) vs 6.03 (95% CI, 5.92–6.15; P < 0.01)] pH probes. Proximal esophageal reflux was not detected in patients who had a negative pepsin assay (N = 12); in contrast, proximal esophageal reflux was documented in three of four patients with a positive assay. In conclusion, detection of pepsin in the saliva and/or sputum may provide a noninvasive method to test for the proximal reflux of gastric contents.

Multi-Center Study: The Biochemical Efficacy, Safety and Tolerability of a New α1-Proteinase Inhibitor, Zemaira

Augmentation therapy with a plasma derived α1-Proteinase Inhibitor (α1-PI) has been demonstrated to be effective in restoring serum Alpha1-antitrypsin (AAT)* levels in individuals with AAT Deficiency (note: α1 PI and AAT are synonymous). The objective of this study was to demonstrate that the steady-state trough serum α1-PI levels, achieved by a new plasma derived α1-PI (Zemaira, study drug, ZLB Behring LLC, King of Prussia, Pennsylvania, USA), were bioequivalent to those achieved by the currently available α1-PI therapy, Prolastin (control drug, Bayer Corporation, Berkeley, California, USA), and maintained weekly trough serum antigenic α1-PI levels above the protective threshold of 11 μ M. This multi-center, controlled study randomized a total of 44 subjects to receive either study or control drug for a 10-week double-blind phase. The control group was then crossed over to receive the study drug for the remainder of the study (14 weeks). The difference in mean trough serum antigenic α1-PI level between the treatment groups was 1.45 μ M (90% CI-2.77, −0.13), signifying bioequivalence. The mean trough serum antigenic α1-PI level in the study drug group was greater than the therapeutic threshold of 11 μ M, achieving a level of 17.7 μ M during the steady-state period. Treatment-related adverse events (AEs) were seen in 7% and 21% of study and control drug treated subjects, respectively. No documented viral transmission occurred. These results demonstrate that the new plasma derived α1-PI (Zemaira) is bioequivalent to the currently available product Prolastin, is well tolerated, and safe with respect to the risk of viral transmission.

Safety and Pharmacokinetics of 120 mg/kg versus 60 mg/kg Weekly Intravenous Infusions of Alpha-1 Proteinase Inhibitor in Alpha-1 Antitrypsin Deficiency: A Multicenter, Randomized, Double-Blind, Crossover Study (SPARK)

Abstract Augmentation therapy with the approved dose of 60 mg/kg weekly intravenous (IV) alpha-1 proteinase inhibitor (alpha1-PI), achieves a trough serum level of 11 μM in individuals with alpha-1 antitrypsin deficiency (AATD), yet this is still below the level observed in healthy individuals. This study assessed the safety and pharmacokinetic profile of weekly infusions of a 120 mg/kg dose of alpha1-PI in 30 adults with AATD. Subjects with symptomatic, genetically determined (genotypes PI*ZZ, PI*Z(null), PI*(null)(null) or PI*(Z)Mmalton) AATD were randomly assigned to weekly infusions of 60 or 120 mg/kg alpha1-PI (Prolastin-C®) for 8 weeks before crossing over to the alternate dose for 8 weeks. Adverse events (AEs) (including exacerbations), vital signs, pulmonary function tests, and laboratory assessments were recorded. Pharmacokinetic measurements included AUC0-7days, Cmax, trough, tmax, and t1/2, based on serum alpha1-PI concentrations. In total for both treatments, 112 AEs were reported, with exacerbation of COPD being the most frequent, consistent with the subjects’ diagnoses. Mean steady-state serum alpha1-PI concentrations following 120 mg/kg weekly IV alpha1-PI were higher than with the 60 mg/kg dose and mean trough concentrations were 27.7 versus 17.3 μM, respectively. Dose proportionality was demonstrated for AUC0-7days and Cmax, with low inter-subject variability. The 120 mg/kg alpha1-PI weekly dose was considered to be safe and well tolerated, and provided more favorable physiologic alpha1-PI serum levels than the currently recommended 60 mg/kg dose. The effect of this dosing regimen on slowing and/or preventing emphysema progression in subjects with AATD warrants further investigation.

Serum concentrations of vitamin D-binding protein (Group-specific component) in cystic fibrosis

SummaryVitamin D-binding protein (DBP) concentrations were determined in the sera of 90 cystic fibrosis homozygotes, 57 obligate heterozygotes, and 46 normal controls. Very significantly lower mean concentrations were found in the sera of CF homozygotes compared with both heterozygotes and controls (P<0.01, Wilcoxon Rank Sums Test). Subdivision of the samples by Gc phenotype showed that this relationship held true both in the Gc1 and Gc2-1 phenotypes. The small sample size of the Gc2 genotype makes the significance levels of limited usefulness, but the pattern of variation of DBP levels among CF homozygotes, heterozygotes, and controls was consistent with that observed for the Gc1 and Gc2-1 classes. Haptoglobin levels showed high coefficients of variation when compared among CF homozygotes, obligate heterozygotes, and controls, presumably because of nonspecific elevation in the acute-phase response. Alpha2-macroglobulin levels were, if anything, slightly elevated in CF homozygotes compared with controls, while albumin levels showed no significant mean differences between these groups. Since the DBP concentration does not vary with age nor with levels of vitamin D and its metabolites, we interpret our results to mean that DBP levels are specifically decreased in cystic fibrosis, perhaps as the result of impaired glycosylation of the protein.

Resistance of tropoelastin and elastin peptides to degradation by α2-macroglobulin-protease complexes☆

Abstract Previous studies have suggested that the complex of neutrophil elastase and α2-macroglobulin can degrade tropoelastin, the 70,000-dalton soluble intermediate in the biosynthesis of insoluble elastin. Such complexes could, therefore, play an important role in the development of emphysema. Therefore, complexes of human α2-macroglobulin with homogeneous human neutrophil elastase, porcine pancreatic elastase, or bovine trypsin were isolated by gel filtration chromatography and tested for their ability to degrade tropoelastin. While tropoelastin was rapidly degraded by the free enzymes, it was not affected by the complexes. However, peptides of molecular weight 8500 or less, prepared by mild acid hydrolysis of insoluble elastin, interacted with the catalytically active enzyme in the complex, while larger peptides did not. These findings suggest that α2-macroglobulin-elastase complexes do not, themselves, play a role in the initial degradation of either tropoelastin or insoluble elastin.

Pharmacokinetic comparability of Prolastin®-C to Prolastin® in alpha1-antitrypsin deficiency: a randomized study

BackgroundAlpha1-antitrypsin (AAT) deficiency is characterized by low blood levels of alpha1-proteinase inhibitor (alpha1-PI) and may lead to emphysema. Alpha1-PI protects pulmonary tissue from damage caused by the action of proteolytic enzymes. Augmentation therapy with Prolastin® (Alpha1-Proteinase Inhibitor [Human]) to increase the levels of alpha1-PI has been used to treat individuals with AAT deficiency for over 20 years. Modifications to the Prolastin manufacturing process, incorporating additional purification and pathogen-reduction steps, have led to the development of an alpha1-PI product, designated Prolastin®-C (Alpha1-Proteinase inhibitor [Human]). The pharmacokinetic comparability of Prolastin-C to Prolastin was assessed in subjects with AAT deficiency.MethodsIn total, 24 subjects were randomized to receive 60 mg/kg of functionally active Prolastin-C or Prolastin by weekly intravenous infusion for 8 weeks before crossover to the alternate treatment for another 8 weeks. Pharmacokinetic plasma samples were drawn over 7 days following last dose in the first treatment period and over 10 days following the last dose in the second period. The primary end point for pharmacokinetic comparability was area under the plasma concentration versus time curve over 7 days post dose (AUC0-7 days) of alpha1-PI determined by potency (functional activity) assay. The crossover phase was followed by an 8-week open-label treatment phase with Prolastin-C only.ResultsMean AUC0-7 days was 155.9 versus 152.4 mg*h/mL for Prolastin-C and Prolastin, respectively. The geometric least squares mean ratio of AUC0-7 days for Prolastin-C versus Prolastin had a point estimate of 1.03 and a 90% confidence interval of 0.97-1.09, demonstrating pharmacokinetic equivalence between the 2 products. Adverse events were similar for both treatments and occurred at a rate of 0.117 and 0.078 per infusion for Prolastin-C (double-blind treatment phase only) and Prolastin, respectively (p = 0.744). There were no treatment-emergent viral infections in any subject for human immunodeficiency virus, hepatitis B or C, or parvovirus B19 during the course of the study.ConclusionProlastin-C demonstrated pharmacokinetic equivalence and a comparable safety profile to Prolastin.Trial RegistrationClinicalTrials.gov Identifier: NCT00295061

Alpha-1-antitrypsin (Pi) types in Korean and Chinese populations

SummaryAlpha-1-antitrypsin phenotypes were determined by isoelectric focusing in 270 Koreans and 52 Chinese. The frequencies of the major alleles were the following, numbers for the Chinese sample are in parentheses: PiM1: 0.65 (0.66), PiM2: 0.22 (0.25), PiM3: 0.06 (0.09). Other alleles, including PiZ were present in low frequencies. The Koreans appear to be quite similar to the Chinese in this system.

Alpha1-antitrypsin deficiency genes: Contributory defect in a subset of psoriatics?

Since proteolytic processes are prominent in psoriasis, sera of forty-five psoriatics were examined for alpha 1-antitrypsin (alpha 1-AT) phenotype and eighteen sera, for alpha 1-AT content and function. Five sera (11.1%) had heterozygous phenotypes (2 MZ and 3 MS), a prevalence of Z and S variants similar to that reported in nonpsoriatic populations. Two of three variants examined for content and function exhibited marked reductions. Since MZ heterozygotes are almost always, and MS phenotypes sometimes, associated with decreased serum alpha 1-AT levels, and since Z and MZ phenotypes are associated with increased hepatic fibrosis or cirrhosis, these variants may be relevant to problems of spontaneous fibrosis or methotrexate-induced hepatotoxicity in psoriasis. alpha 1-AT deficiency may also contribute to guttate flares with infection and to increased O-2 . production by psoriatic sera-stimulated polymorphonuclear leukocytes (PMNs). Although no evidence exists that psoriasis is more prevalent among persons with hypomorphic alpha 1-AT phenotypes, such defects may contribute to severity of inflammation and hyperplasia.

A rapid and quantitative method for the determination of interleukin-1α and -β mRNA expression in human monocytes and macrophages

Abstract We have used IL-1α and IL-1β specific RNA standards in an RNA dot blot assay to rapidly and quantitatively assess the differential expression of the two human interleukin-1 mRNAs. This approach enabled us to minimize inaccuracies due to differences in specific activities of the probes, transcript size, and transfer and/or hybridization efficiencies of the two transcripts. We were thus able to accurately determine the steady state levels and molar ratio of IL-1 mRNA in human peripheral blood monocytes (PBM) and alveolar macrophages (AM). PBM, upon stimulation by lipopolysaccharide (LPS), expressed approximately ten-fold more IL-1β mRNA than IL-1α. AM, however, expressed only two-fold more IL-1β then IL-1α. PBM aged in vitro for 7 days prior to LPS stimulation, expressed at least 20-fold more IL-1β than IL-1α RNA and at levels significantly lower than either PBM or AM.

Alpha-1-antitrypsin from mouse serum: Isolation and characterization

Alpha-1-antitrypsin (alpha-1-protease inhibitor) was isolated from mouse serum by a series of electrophoretic and chromatographic steps. We found it to be a glycoprotein of a mass ratio of 57.7 Kd. The extinction coefficient was E1%1cm,280=4.74. It inhibits bovine trypsin, human granulocytic and porcine pancreatic elastase. Its concentration in serum differs between inbred strains. Of those tested the concentration in C57BL/6J males was lowest with 5.58 +/- 0.71 mg/ml (females: 3.02 +/- 0.39) and that in DBA/2J was highest: 8.5 +/- 0.87 mg/ml (females: 4.09 +/- 0.51). The concentration of alpha-1-antitrypsin in male serum was almost twice as high as that in females of all strains tested.