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H Bodenmüller

Publications and source records attributed to H Bodenmüller.

32 records · Page 2Linked to original sources
PubMed1984

The hydra head activator in human blood circulation. Degradation of the synthetic peptide by plasma angiotensin-converting enzyme.

Using methanol extraction combined with HPLC and a new radioimmunoassay, the peptide head activator was detected in human plasma at a concentration of 20-100 fmol/ml. Synthetic head activator incubated with plasma was degraded with a half-life of 7 min. Analysis of sites of enzymatic cleavage and inhibition by captopril showed a major involvement of angiotensin-converting enzyme in this process. Endogenous head activator, on the other hand, was not appreciably degraded upon incubation of plasma in vitro. These findings raise the possibility that the endogenous peptide could bind to a protective carrier molecule and reach potential target tissues via the blood circulation.

Chromatography, High Pressure Liquid↗
PubMed1984

Enzyme-linked immunosorbent assay for the neuropeptide 'head activator'.

By exposing different sites of the 'head activator', different sets of antibodies were designed and produced which recognised either the amino or the carboxy terminus of the free 'head activator', which reacted with 'head activator' in a tissue-fixed conformation, or which bound to the 'head-activator' sequence, if it was part of a larger precursor-like molecule. An enzyme-linked immunosorbent assay (ELISA) was developed to characterise the antibodies and also to assay minute amounts of 'head activator' or 'head-activator'-like immunoreactivities in animal or tissue extracts. A competitive ELISA is described which uses biotin-avidin for enhancement. The assay is sensitive with an antibody specific for the amino terminus in the range of 0.5-50 fmol, with an antibody specific for the carboxy terminus in the range of 20-400 fmol. The ELISA specific for the amino terminus is 10-times more sensitive than a radio-immunoassay with tritiated 'head activator' [H. Bodenmüller and B. Zachmann (1983) FEBS Lett. 159,237-240]. Previously no radioimmunoassay existed with specificity for the carboxy terminus.

Antibody Specificity↗
PubMed1981

Isolation and amino acid sequence of a morphogenetic peptide from hydra.

From Anthopleura elegantissima and from Hydra attenuata, a morphogenetic peptide-the head activator-was isolated in pure form. The sequence of the head activator was established by enzymatic and by chemical degradation of the whole peptide or fragments thereof and subsequent analysis of the amino acids by micromethods. The head activator from both sources was identical and has the sequence:<pGlu-Pro-Pro-Gly-Gly-Ser-Lys-Val-Ile-Leu-Phe.

Journal Article↗
PubMed1980

Virotoxins: actin-binding cyclic peptides of Amanita virosa mushrooms.

Virotoxins are toxic peptides singularly found in Amanita virosa mushrooms. After purification and resolution by high-pressure liquid chromatography, the main component, viroisin, was selectively cleaved and submitted to Edman degradation. The structure could be completely elucidated and was in part found to be the same as in phallotoxins. Differing from the phallotoxins, however, virotoxins are monocyclic peptides and contain D-serine instead of L-cysteine. In addition, two amino acids were detected in virotoxins which thus far have not been found in nature: 2,3-trans-3,4-dihydroxy-L-proline and 2'-(methylsulfonyl)-L-tryptophan. The biological activity of viroisin is comparable to that of the phallotoxins: e.g., with 2.5 mg of viroisin per kg (white mouse), 50% of the animals die within 2-5 h by hemorrhagia of the liver. Also, on the molecular level, the virotoxins behave similar to the phallotoxins. Thus, viroisin binds to rabbit muscle actin as proved by difference UV spectroscopy. With an apparent equilibrium dissociation constant KD approximately 2 x 10(-8) M, the affinity of viroisin is very similar to that of phalloidin. However, the flexibility of the monocyclic structure and the presence of two additional hydroxy groups in the virotoxins suggest a different mode of interaction with actin. While there is proof that the bicyclic phallotoxins possess a rigid binding site, the virotoxins may adopt the biologically active conformation by an induced-fit mechanism upon contact with actin.

Actins↗
PubMed1980

Amaninamide, a new toxin of Amanita virosa mushrooms.

Amaninamide, a toxin closely related to the family of amatoxins, was found exclusively in Amanita virosa mushrooms. It differs from the well known toxin alpha-amanitin in that it lacks the 6'-hydroxyl group of the tryptophan unit, and from the toxin amanin found in Amanita phalloides by the presence of a carboxamide group instead of a carboxylic acid groups.

Agaricales↗
PubMed1980

Human hypothalamus and intestine contain a hydra-neuropeptide.

From human hypothalamus and intestine a substance was isolated which has the same physico-chemical and biological properties as the head activator from hydra. The hypothalamus of an adult man contained activity corresponding to at least 10(8) hydra. An intestine of a 3-month-old human embryo contained approx. 10(5) hydra equivalents and that of a 6-month-old embryo 10(6). A gradual increase in content of head activator during development was also found in rat intestine.

Animals↗
PubMedDate not supplied

Immunohistochemical profiles of 30 monoclonal antibodies against cytokeratins 8, 18 and 19. Second report of the TD5 workshop.

In the first report of the TD5 workshop (TD5-1), the epitope specificities of 30 different monoclonal antibodies against cytokeratins 8, 18 and 19 were determined. This second report presents the immunohistochemical profiles of these antibodies using human appendix and normal skin for evaluation. Each antibody was tested by one or two different laboratories recruited from the Dutch Working Group on Immunohistochemistry and Cytochemistry. Eight different laboratories participated. The histological specimens were pretreated by the participants in three different ways for immunohistochemistry: microwave antigen retrieval in citrate buffer, enzymatic digestion to restore epitope exposure, no specific treatment (untreated paraffin-embedded samples), and tested blindly without knowledge of cytokeratin or epitope specificity of the antibodies at three different concentrations of 50, 10 and 1 microg/ml. Most of the tested antibodies (29/30) were useful in at least one pretreatment method, with microwave antigen retrieval being the most sensitive approach. For some antibodies, very high backgrounds were observed. Furthermore, it can be concluded that 11 MAbs performed well using all three staining protocols, including untreated paraffin-embedded sections. Interestingly, all the antibodies with documented selected specificity towards cytokeratin 8 (i.e. 178, 191, 199, 202 and 206) are reactive with an immunodominant region corresponding to amino acids 340-365 on cytokeratin 8, which evidently is well-suited as target for immunohistochemical interactions. Similarly, three antibodies with the same capacity to react with untreated samples had specificity against cytokeratin 19 (i.e. 179, 197 and 204) in the corresponding region in this filament, i.e. amino acids 311-335, or the KS 19.1 epitope. None of the six antibodies against the other major cytokeratin 19 epitope (BM 19.21) were found useful for immunohistochemistry on untreated samples. The overall conclusions from the present investigation are that all cytokeratin-8-specific antibodies with defined epitope specificities were very useful. Only one of the major two epitopes on cytokeratin 19 seems to be available for efficient immunohistochemistry. Cytokeratin 18 exposes some epitopes outside the immunodominant region reactive with the antibodies 190, 203 and 205 which can be used for untreated samples. The implications of these findings are of significance both for diagnostic histopathology and for the biology of tumor marker epitope expression in tissues.

Animals↗
PubMedDate not supplied

The tumor markers TPA, TPS, TPACYK and CYFRA 21-1 react differently with the keratins 8, 18 and 19.

The commercially available tumor marker tests TPA, TPS, TPACYK and CYFRA 21-1 react with simple epithelium keratins. From clinical studies it can be deduced that the pattern of keratin recognition must be different for each of these tests. We therefore studied the reactivity of the keratin fragment combinations K8/K18 and K8/K19 in the different tests and determined the reactivity of the corresponding soluble antibodies with purified keratin 8, 18 and 19 in immunoblots. TPS and CYFRA 21-1 were found to distinguish clearly between the keratin fragment combinations K8/K18 (TPS) and K8/K19 (CYFRA 21-1). TPA and TPACYK reacted with both combinations, however, with different intensities. On immunoblots the CYFRA 21-1 antibodies reacted exclusively with K19, whereas the antibodies of the other assays reacted with at least 2 of the keratins investigated.

Antibodies↗
PubMedDate not supplied

Lung cancer-associated keratin 19 fragments: development and biochemical characterisation of the new serum assay Enzymun-Test CYFRA 21-1.

From a panel of 4 murine monoclonal antibodies directed against keratin 19 various antibody combinations were evaluated in solid-phase enzyme-linked sandwich immunoassays for detection of soluble keratin 19 fragments in patient sera. One of these antibody combinations, comprised of the monoclonal antibodies Ks 19.1 and BM 19.21, was selected for further development to a routine test (Enzymun-Test CYFRA 21-1) because of its high diagnostic sensitivity and specificity for non-small cell lung carcinoma (NSCLC). Both antibodies are specific for keratin 19, no reactivity could be observed with cytokeratin 8 or 18. The epitopes of the two antibodies were determined to be within helix 2B of the rod romain. The epitope sequences lie within the sequence 311-335 for the catcher antibody Ks 19.1 and 346-367 for the detector antibody BM 19.21. These sequences are unique, as could be confirmed from sequence databases. The standard material for the assay was prepared from a cytoskeleton fraction of cultivated MCF-7 cells. Subsequent digestion of this fraction with chymotrypsin yielded a soluble and stable standard material. Both the standard material and the serum analyte appeared as oligomers when analysed on gel chromatography: the serum analyte appeared exclusively at a M(r) of 100 +/- 10 kD, whereas the standard material eluted in fractions corresponding to 100 +/- 10 kD and 450 kD. Due to the precise definition of the antigen and the localisation of the antibody binding sequences, Enzymun-Test CYFRA 21-1 is one of the best characterised tumor markers so far.

Animals↗