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1.
Nervenarzt ; 83(4): 450-7, 2012 Apr.
Article in German | MEDLINE | ID: mdl-22038386

ABSTRACT

BACKGROUND: The increasing therapeutic options for relapsing-remitting multiple sclerosis require a specific treatment and risk management to recognize the individual response as well as potential side effects. To switch from pure MS documentation to MS management by implementing a new multiple sclerosis management and documentation tool may be of importance. METHOD: This article presents the novel computer-based patient management system "multiple sclerosis management system 3D" (MSDS 3D). RESULTS: MSDS 3D allows documentation and visualization of visit schedules and mandatory examinations via defined study modules by integration of data input from patients, attending physicians and MS nurses. It provides forms for the documentation of patient visits as well as clinical and diagnostic findings. Information is collected via interactive touch screens. A specific module which is part of MSDS 3D's current version allows the monthly monitoring of patients under treatment with natalizumab. A checklist covering clinical signs of progressive multifocal leukoencephalopathy (PML) and a detailed questionnaire about the handling of natalizumab in practice have additionally been added. DISCUSSION: The MS patient management system MSDS 3D has successfully been implemented and is currently being evaluated in a multi-centre setting. Advanced assessment of patient data may allow improvements in clinical practice and research work. The addition of a checklist and a questionnaire into the natalizumab module may support the recognition of PML during its early, treatable course.


Subject(s)
Antibodies, Monoclonal, Humanized/administration & dosage , Decision Support Systems, Clinical/organization & administration , Documentation/methods , Multiple Sclerosis/diagnosis , Multiple Sclerosis/drug therapy , Telemedicine/methods , Therapy, Computer-Assisted/methods , Diagnosis, Computer-Assisted/methods , Humans , Natalizumab , Software , User-Computer Interface
2.
Mol Cell Biol ; 16(10): 5409-18, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8816453

ABSTRACT

The elevation of cyclic AMP (cAMP) levels in the cell downregulates the activity of the Raf-1 kinase. It has been suggested that this effect is due to the activation of cAMP-dependent protein kinase (PKA), which can directly phosphorylate Raf-1 in vitro. In this study, we confirmed this hypothesis by coexpressing Raf-1 with the constitutively active catalytic subunit of PKA, which could fully reproduce the inhibition previously achieved by cAMP. PKA-phosphorylated Raf-1 exhibits a reduced affinity for GTP-loaded Ras as well as impaired catalytic activity. As the binding to GTP-loaded Ras induces Raf-1 activation in the cell, we examined which mechanism is required for PKA-mediated Raf-1 inhibition in vivo. A Raf-1 point mutant (RafR89L), which is unable to bind Ras, as well as the isolated Raf-1 kinase domain were still fully susceptible to inhibition by PKA, demonstrating that the phosphorylation of the Raf-1 kinase suffices for inhibition. By the use of mass spectroscopy and point mutants, PKA phosphorylation site was mapped to a single site in the Raf-1 kinase domain, serine 621. Replacement of serine 621 by alanine or cysteine or destruction of the PKA consensus motif by changing arginine 618 resulted in the loss of catalytic activity. Notably, a mutation of serine 619 to alanine did not significantly affect kinase activity or regulation by activators or PKA. Changing serine 621 to aspartic acid yielded a Raf-1 protein which, when expressed to high levels in Sf-9 insect cells, retained a very low inducible kinase activity that was resistant to PKA downregulation. The purified Raf-1 kinase domain displayed slow autophosphorylation of serine 621, which correlated with a decrease in catalytic function. The Raf-1 kinase domain activated by tyrosine phosphorylation could be downregulated by PKA. Specific removal of the phosphate residue at serine 621 reactivated the catalytic activity. These results are most consistent with a dual role of serine 621. On the one hand, serine 621 appears essential for catalytic activity; on the other hand, it serves as a phosphorylation site which confers negative regulation.


Subject(s)
Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins/metabolism , Serine , Alanine , Amino Acid Sequence , Animals , Binding Sites , Blotting, Western , COS Cells , Chlorocebus aethiops , Cloning, Molecular , Consensus Sequence , Cysteine , Homeostasis , Humans , Molecular Sequence Data , Mutagenesis, Site-Directed , Peptide Fragments/chemistry , Peptide Fragments/isolation & purification , Peptide Mapping , Phosphorylation , Point Mutation , Protein Serine-Threonine Kinases/biosynthesis , Protein Serine-Threonine Kinases/chemistry , Proto-Oncogene Proteins/biosynthesis , Proto-Oncogene Proteins/chemistry , Proto-Oncogene Proteins c-raf , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Transfection
3.
Oncogene ; 20(9): 1052-62, 2001 Mar 01.
Article in English | MEDLINE | ID: mdl-11314042

ABSTRACT

The adapter Grb2 is an important mediator of normal cell proliferation and oncogenic signal transduction events. It consists of a central SH2 domain flanked by two SH3 domains. While the binding specificities of the Grb2 SH2 and N-terminal SH3 domain [Grb2 SH3(N)] have been studied in detail, binding properties of the Grb2 SH3(C) domain remained poorly defined. Gab1, a receptor tyrosine kinase substrate which associates with Grb2 and the c-Met receptor, was previously shown to bind Grb2 via a region which lacks a Grb2 SH3(N)-typical motif (P-x-x-P-x-R). Precipitation experiments with the domains of Grb2 show now that Gab1 can bind stably to the Grb2 SH3(C) domain. For further analyses, Gab1 mutants were generated by PCR to test in vivo residues thought to be crucial for Grb2 SH3(C) binding. The Grb2 SH3(C) binding region of Gab1 has significant homology to a region of the adapter protein SLP-76. Peptides corresponding to epitopes SLP-76, Gab1, SoS and other proteins with related sequences, as well as mutant peptides were synthesized and analysed by tryptophan-fluorescence spectrometry and by in vitro competition experiments. These experiments define a 13 amino acid sequence with the unusual consensus motif P-x-x-x-R-x-x-K-P as required for a stable binding to the SH3(C) domain of Grb2. Additional analyses point to a distinct binding specificity of the Grb2-homologous adapter protein Mona (Gads), indicating that the proteins of the Grb2 adapter family may have partially overlapping, yet distinct protein binding properties.


Subject(s)
Adaptor Proteins, Signal Transducing , Phosphoproteins/metabolism , Proline/chemistry , Proteins/metabolism , src Homology Domains , Amino Acid Sequence , Blotting, Western , Carrier Proteins/metabolism , Cells, Cultured , Consensus Sequence , Electrophoresis, Polyacrylamide Gel , GRB2 Adaptor Protein , Glutathione Transferase/metabolism , Humans , Molecular Sequence Data , Oligodeoxyribonucleotides , Peptide Fragments/metabolism , Phosphoproteins/genetics , Point Mutation , Precipitin Tests , Protein Binding , Proteins/genetics , Recombinant Fusion Proteins/metabolism , Spectrometry, Fluorescence , Tryptophan/chemistry
4.
Protein Sci ; 4(3): 421-32, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7795526

ABSTRACT

The primary structural features that render human monoclonal light chains amyloidogenic are presently unknown. To gain further insight into the physical and biochemical factors that result in the pathologic deposition of these proteins as amyloid fibrils, we have selected for detailed study three closely homologous protein products of the light-chain variable-region single-gene family VkIV. Two of these proteins, REC and SMA, formed amyloid fibrils in vivo. The third protein, LEN, was excreted by the patient at levels of 50 g/day with no indication of amyloid deposits. Sequences of amyloidogenic proteins REC and SMA differed from the sequence of the nonpathogenic protein LEN at 14 and 8 amino acid positions, respectively, and these amino acid differences have been analyzed in terms of the three-dimensional structure of the LEN dimer. To provide a replenishable source of these human proteins, we constructed synthetic genes coding for the REC, SMA, and LEN variable domains and expressed these genes in Escherichia coli. Immunochemical and biophysical comparisons demonstrated that the recombinant VkIV products have tertiary structural features comparable to those of the patient-derived proteins. This well-defined set of three clinically characterized human kIV light chains, together with the capability to produce these kIV proteins recombinantly, provide a system for biophysical and structural comparisons of two different amyloidogenic light-chain proteins and a nonamyloidogenic protein of the same subgroup. This work lays the foundation for future investigations of the structural basis of light-chain amyloidogenicity.


Subject(s)
Amyloid/immunology , Amyloidosis/immunology , Bence Jones Protein/immunology , Immunoglobulin Variable Region/immunology , Immunoglobulin kappa-Chains/immunology , Amino Acid Sequence , Base Sequence , Bence Jones Protein/isolation & purification , Genes, Synthetic , Humans , Immunoglobulin Variable Region/genetics , Immunoglobulin kappa-Chains/genetics , Models, Molecular , Molecular Sequence Data , Protein Conformation , Protein Denaturation , Recombinant Fusion Proteins/immunology , Recombinant Proteins/immunology , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid
5.
FEBS Lett ; 270(1-2): 222-4, 1990 Sep 17.
Article in English | MEDLINE | ID: mdl-2226783

ABSTRACT

The amino acid sequence of the acrosin-trypsin inhibitor HUSI-II from human seminal plasma is presented which unequivocally identifies HUSI-II as being of Kazal-type. In addition, the HUSI-II sequence shows a striking similarity to the middle part of glycoprotein hormone beta-subunits thus revealing a hitherto unknown structural and evolutionary relationship between Kazal-type inhibitors and glycoprotein hormones.


Subject(s)
Acrosin/antagonists & inhibitors , Trypsin Inhibitor, Kazal Pancreatic/chemistry , Trypsin Inhibitors/chemistry , Amino Acid Sequence , Glycoproteins/chemistry , Hormones/chemistry , Humans , Molecular Sequence Data , Semen/chemistry , Sequence Homology, Nucleic Acid , Serine Peptidase Inhibitors, Kazal Type
6.
J Immunol Methods ; 13(3-4): 261-70, 1976.
Article in English | MEDLINE | ID: mdl-796387

ABSTRACT

The unlabeled antibody enzyme method was used to delineate the anatomical distribution of lymphocytes positive with a MBtheta and a-MIg in tissue sections of thymus, spleen, lymph nodes and Peyer's patches of mice. The known T- and B-cell areas were established. Moreover, individual B-cells are detected in T-cell regions, especially in the thymus medulla, and in the periarteriolar section of spleen white pulp. Similarly, individual T-cells occur in B-cell areas, namely in the marginal zone of spleen white pulp, in the medullar cores of lymph nodes, and in germinal centers.


Subject(s)
B-Lymphocytes/immunology , Fluorescent Antibody Technique , Lymphoid Tissue/immunology , Receptors, Antigen, B-Cell/analysis , T-Lymphocytes/immunology , Animals , Lymph Nodes/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Inbred CBA , Peyer's Patches/immunology , Spleen/immunology , Thymus Gland/immunology
7.
J Immunol Methods ; 42(3): 367-74, 1981.
Article in English | MEDLINE | ID: mdl-7288189

ABSTRACT

A simple method has been established for tritium labeling immunoglobulins. This label avoids certain disadvantages of 125iodine such as high radiation hazard and requirement for frequent labeling owing to the short half-life of this isotope. High specific activities (range 1.8-9.0 cpm/mu g protein) were obtained with no loss of functional activity as demonstrated by passive hemagglutination. The labeled conjugate is especially suitable for detection of activity in hybridoma supernatants by indirect binding assay. Adapted to microtiter plates, the method is suitable for large numbers of samples, e.g. up to 800 supernatants may be examined daily. The utility and advantages of the binding assay with respect to reproducibility, sensitivity, binding kinetics, easy and rapid performance are described.


Subject(s)
Antibodies, Monoclonal , Antibody Specificity , Immunoglobulins/metabolism , Propionates/pharmacology , Succinimides/pharmacology , Animals , Binding Sites, Antibody , Cross-Linking Reagents/pharmacology , Goats , Mice , Mice, Inbred AKR , Radioimmunoassay , Tritium
8.
Transplantation ; 35(3): 249-54, 1983 Mar.
Article in English | MEDLINE | ID: mdl-6340277

ABSTRACT

The in vivo and in vitro effectiveness of several monoclonal antimouse T and B cell antibodies, of anti-Th-1 and of Iak serum, as well as of ATG were compared. The parameters were prolongation of skin graft survival, prevention of graft-versus-host disease (GVHD), antibody and primary and secondary plaque formation against sheep redblood cells (RBCs), and T cell depletion of lymphoid tissues. In general, in vitro effectiveness of the monoclonal antibodies exceeded their in vivo effectiveness. Skin graft survival was prolonged by ATG, but not by monoclonal anti-T, or anti-T plus anti-B antibody. GVHD was prevented by in vitro incubation of donor bone marrow with monoclonal anti-Th-1, but in vivo treatment of marrow donors was ineffective. Treatment with ATG was successful. Anti Iak antibody blocked plaque formation by spleen cells incubated with sheep RBCs, but had no effect on secondary plaque formation when given in vivo. Neither was there any in vivo effect of anti-Iak or anti-Th-1 on antisheep RBC agglutinin formation. ATG was effective in both of these assays, although its cytotoxic and complement-fixing titer did not exceed that of anti-Th-1 or anti-Iak. Although anti-Th-1 was cleared more rapidly from the serum of mice expressing the corresponding Th-1 alloantigen, than from mice with the noncorresponding alloantigen and although anti-Th-1 was shown to bind to the T cell areas of the lymphoid tissue, it did not--unlike ATG--deplete these areas of T cells. Possible reasons for the difference in effectiveness of in vitro and in vivo application of these monoclonal antibodies are discussed.


Subject(s)
Antibodies, Monoclonal/immunology , Antilymphocyte Serum , Bone Marrow Transplantation , Immunosuppression Therapy , Animals , Antibody Formation , Graft vs Host Reaction , Hemolytic Plaque Technique , Mice , Mice, Inbred Strains , Skin Transplantation , T-Lymphocytes/immunology , Transplantation Immunology
9.
Immunobiology ; 201(3-4): 332-46, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10776790

ABSTRACT

CD8-positive cytotoxic T cells (CTL) recognize antigenic peptides in combination with major histocompatibility complex (MHC) class I molecules on the surface of syngeneic antigen presenting cells (APC). In the present paper we show that cells from tumor antigen-specific CTL clones present their cognate antigenic peptide to other CTL from the same clone. Inter-CTL peptide presentation resulted in activation of the cells of one CTL clone to MHC-unrestricted lysis of bystander cells. In contrast to the behaviour of this clone, another CTL clone did not lyse bystander cells after incubation with the cognate peptide, but was activated to self-destruction. The human herpes virus Epstein-Barr virus is involved in the pathogenesis of a broad spectrum of human neoplasias. Using freshly established non-clonal T cells with specificity for a peptide derived from an Epstein-Barr virus encoded antigen we found again lysis of MHC mismatched bystander cells as a consequence of inter-CTL peptide presentation, indicating that bystander lysis following antigen self-presentation is not a phenomenon restricted to long-term in vitro cultured T cell clones. The potential implications for immunosurveillance against cancer and for tumor escape mechanisms are discussed.


Subject(s)
Antigen Presentation/immunology , T-Lymphocytes, Cytotoxic/immunology , Cell Line, Transformed , Cytotoxicity, Immunologic , HLA-A2 Antigen/immunology , Humans , Tumor Cells, Cultured
10.
Am J Clin Pathol ; 116(1): 135-42, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11447744

ABSTRACT

The human amyloidoses represent a heterogeneous group of disorders characterized by the deposition of fibrillar protein in vital organs. Given the fact that at least 20 different molecules can form fibrils, the unambiguous identification of the type of amyloid deposited is critical to the correct diagnosis and treatment of patients with these disorders. Heretofore, this information has been inferred from particular clinical features of the disease, ancillary laboratory tests, and results of immunohistochemical analyses. However, to establish unequivocally the kind of protein that is deposited as amyloid, it is necessary to determine its chemical composition through amino acid sequencing or mass spectroscopy of material extracted from fibrillar deposits. We have developed a micromethod whereby such studies can be performed readily using sections of formalin-fixed, paraffin-embedded biopsy specimens. The ability to identify precisely the nature of the tissue deposits has diagnostic, therapeutic, and prognostic implications for patients with amyloid-associated disorders.


Subject(s)
Amyloid/chemistry , Amyloid/classification , Amyloidosis/metabolism , Amyloidosis/pathology , Amino Acid Sequence/genetics , Biopsy , Fixatives , Formaldehyde , Humans , Immunohistochemistry , Molecular Sequence Data , Paraffin Embedding , Spleen/metabolism , Spleen/pathology , Tissue Extracts/chemistry
11.
J Biochem ; 124(2): 396-403, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9685732

ABSTRACT

The role of the NH2-terminal hydrophobic patch of cytochrome P4502B4 (CYP2B4) in interactions with NADPH-cytochrome P450 reductase (P450R) and cytochrome b5 (b5) was assessed using a variant lacking the signal anchor sequence (Delta2-27). CD, second-derivative, and fluorescence emission spectra indicated that the structure of the deletion mutant slightly differed from that of the native CYP2B4. Fitting of the initial-velocity patterns for P450R- and b5-directed electron transfer to the ferric CYP2B4 forms to Michaelis-Menten kinetics revealed an approximately 2.3-fold decrease in the affinity of the two electron donors for the engineered enzyme, while the reductive efficiency remained unaffected. Circumstantial analysis suggested that impaired association of the redox proteins with P4502B4(Delta2-27) accounted for this phenomenon. Interestingly, spectral docking of P450R to the truncated pigment was not hampered, while the binding of b5 was blocked. The rates of substrate-triggered aerobic NADPH consumption in systems containing CYP2B4(Delta2-27) and P450R were 16 to 56% those obtained with the unchanged hemoprotein. Decelerated cofactor oxidation did not arise on defective substrate binding or perturbed utilization of the substrate-bound oxy complex. Experiments with b5 as the ultimate electron donor hinted at some damage to second-electron transfer to the truncated enzyme. The results are consistent with the proposal that the NH2-terminal hydrophobic region of CYP2B4 might be of importance in preservation of the catalytic competence of the enzyme.


Subject(s)
Aryl Hydrocarbon Hydroxylases , Cytochrome P-450 Enzyme System/chemistry , Cytochrome P-450 Enzyme System/metabolism , Protein Sorting Signals/physiology , Steroid Hydroxylases/chemistry , Steroid Hydroxylases/metabolism , Amino Acid Sequence , Catalysis , Circular Dichroism , Cytochrome P-450 Enzyme System/genetics , Cytochromes b5/metabolism , Electron Transport , Escherichia coli , Gene Deletion , Kinetics , Models, Molecular , Molecular Sequence Data , Mutagenesis, Site-Directed , NADH, NADPH Oxidoreductases/metabolism , NADPH-Ferrihemoprotein Reductase , Oxidation-Reduction , Oxygen/metabolism , Protein Conformation , Protein Sorting Signals/genetics , Sequence Analysis , Steroid Hydroxylases/genetics
14.
Nervenarzt ; 76(8): 967-75, 2005 Aug.
Article in German | MEDLINE | ID: mdl-15806419

ABSTRACT

In the summer of 2001, a nationwide epidemiological multiple sclerosis (MS) register was initiated under the auspices of the German MS Society (DMSG). This project aimed at collecting epidemiological data on the number of patients with MS, course of the disease, and their social situation in Germany. During the 2-year pilot phase, five MS centers with various regional differences and treatment methods participated, leading to a representative selection of patients. In December 2003, standardised data sets of 3,458 MS patients were available for evaluation. After examining the quality of the data, 3,223 sets remained for further analysis. The demographics were similar to those obtained from other epidemiological studies: 72% of the patients were female, mean age was 42.9+/-11.2 years, mean disease duration 12.6+/-8.7 years, and 64% suffered from the relapsing-remitting form of the disease. The median EDSS was 3.0, and 69% of patients had an EDSS

Subject(s)
Multiple Sclerosis/classification , Multiple Sclerosis/epidemiology , Registries , Risk Assessment/methods , Adult , Age Distribution , Epidemiologic Research Design , Female , Germany/epidemiology , Humans , Incidence , Male , Multiple Sclerosis/diagnosis , Pilot Projects , Risk Factors , Sex Distribution , Socioeconomic Factors
15.
Nervenarzt ; 73(2): 144-8, 2002 Feb.
Article in German | MEDLINE | ID: mdl-11975090

ABSTRACT

The MSDS (multiple sclerosis documentation system) has been developed at the Department of Neurology, Technical University of Dresden, Germany, during the last 4 years. The first version of this database application has been in use since October 2000. The MSDS manages information on MS patients, their treating physicians, patient history (symptoms, other diseases, biographical history, family history, habits, medication), clinical signs, results of laboratory examinations (blood chemistry, autoantibodies, borrelia serology, evoked potentials, cranial and spinal cord magnetic resonance imaging), clinical scores relevant for MS, and biosamples. In principle, MSDS allows online data input and semiautomatically generates reports to all general practitioners and neurologists treating the respective patient. Patient information sheets and internal treatment guidelines are part of the system. During a 3-month evaluation, the first version of MSDS was tested at eight university multiple sclerosis ambulatory care units and one general neurology hospital. The overall judgement was favorable. Suggestions for changes and improvements, as well as practical experiences, were considered when developing MSDS 2.0, which will be available by the end of 2001.


Subject(s)
Database Management Systems/organization & administration , Documentation/standards , Medical Records Systems, Computerized/organization & administration , Multiple Sclerosis/diagnosis , Ambulatory Care , Germany , Hospital Information Systems/organization & administration , Humans , Patient Care Team , Quality Assurance, Health Care/organization & administration , Software
16.
Biol Chem Hoppe Seyler ; 366(9): 907-15, 1985 Sep.
Article in English | MEDLINE | ID: mdl-3935132

ABSTRACT

Amyloid fibril proteins were isolated from the spleen of a patient with IgD(lambda)-plasmocytoma by extraction and gel filtration in 5M guanidine hydrochloride. The molecular mass of the predominant polypeptide chain was approximately 5000 Da. Its complete amino-acid sequence was elucidated by stepwise automated degradation of the carboxymethylated polypeptide chain and by structural studies of tryptic and thermolysinolytic cleavage products. The length of the polypeptide chain was 58 to 59 residues and it was homologous to the amino acids in positions 8 through 65 of the variable part of an lambda-type immunoglobulin light chain, which was most closely related to the lambda II subgroup. The N-terminal sequence of this amyloid fibril protein proved to be heterogeneous, indicating cleavage after the amino acids in positions 7 and 8. Peptides from the constant part of the lambda-chain were unexpectedly found in the tryptic digest of the denatured amyloid protein HAR. One polypeptide derived from the constant region was separated from the main component by high performance liquid chromatography. Its amino-acid sequence commenced at position 111 and could be traced in 41 steps. In this case, at least two constant region fragments were shown to be constituents of the amyloid fibril protein. The association of fragments from the variable as well as the constant region is discussed with respect to amyloid formation.


Subject(s)
Amyloid/isolation & purification , Immunoglobulin Constant Regions/isolation & purification , Immunoglobulin Light Chains/isolation & purification , Immunoglobulin Variable Region/isolation & purification , Immunoglobulin lambda-Chains/isolation & purification , Immunoglobulins/isolation & purification , Plasmacytoma/immunology , Amino Acid Sequence , Chromatography, High Pressure Liquid , Humans , Molecular Weight , Peptide Fragments/analysis , Spleen/immunology , Thermolysin , Trypsin
17.
Eur J Biochem ; 89(1): 11-7, 1978 Aug 15.
Article in English | MEDLINE | ID: mdl-29753

ABSTRACT

Toxin I from Anemonia sulcata, a major component of the sea anemone venom, consists of 46 amino acid residues which are linked by three disulfide bridges. The [14C]carboxymethylated polypeptide was sequenced to position 29 by automated Edman degradation. The remaining sequence was determined from cyanogen bromide peptides and from tryptic peptides of the citraconylated [14C]carboxymethylated toxin. Toxin I is homologous to toxin II from Anemonia sulcata and to anthopleurin A, a toxin from the sea anemone Anthopleura xanthogrammica. These toxins constitute a new class of polypeptide toxins. No significant homologies exist with toxin III from Anemonia sulcata nor with known sequences of neurotoxins or cardiotoxins of various origin.


Subject(s)
Cnidaria , Cnidarian Venoms , Sea Anemones , Amino Acid Sequence , Animals , Peptide Fragments/analysis , Species Specificity
18.
Histochemistry ; 43(1): 33-49, 1975.
Article in German | MEDLINE | ID: mdl-1141024

ABSTRACT

Iodine 125, an emitter of beta-radiation with an energy lying between that of tritium and carbon-14, is investigated for its applicability in quantitative autoradiography. Absorption and geometric factors of radiation are elucidated. From this, appropriate measuring conditions are derived. The simultaneous exposure of radioactive standard sources permits the evaluation of absolute amounts of radioactivity. Standard cells with labelled membranes are a suitable source of reference taking into account the physical properties of the isotope. Sheep red blood cells are examined for their suitability as standard cells after enzymatic radioiodination. The absolute number of antigenic substances on the surface of single cells is obtained by determining the specific activity of the labelled antibody molecules, and by measuring the silver grain densities of the cells under investigation and of the standard cells. The radioactivity per standard cell can be assessed by conventional procedures. The new method is applied to the quantification of membrane-bound immunoglobulin molecules of the IgG-type on single human lymphocytes. The determination of an immunologic saturation of the labelled antibody is essential for this purpose. On the lymphocytes of a normal person and of a patient with chronic lymphatic leukaemia quite different amounts of immunoglobulins have been evaluated.


Subject(s)
Autoradiography/methods , Absorption , Animals , Cell Membrane , Cells , Erythrocytes , Humans , Immunoglobulin G/analysis , Iodine Radioisotopes , Leukemia, Lymphoid/immunology , Lymphocytes , Protein Binding , Sheep
19.
Hoppe Seylers Z Physiol Chem ; 363(11): 1347-58, 1982 Nov.
Article in English | MEDLINE | ID: mdl-6816713

ABSTRACT

The complete amino acid sequence of the variable region of Bence-Jones protein Mev. from a patient suffering from multiple myeloma and generalized amyloidosis is presented. The amino acid sequence of the Bence-Jones protein Mev. is related to other human kappa-immunoglobulin L-chains of subgroup I. With valine established in Position 191 of the constant region, it is of the Inv (3) allotype. Two types of the Bence-Jones protein Mev. were found, one beginning with the typical N-terminal aspartic acid, and another lacking the N-terminal tripeptide and commencing with methionine in Position 4. A unique insertion of glutamic acid after Position 95 was found in the Bence-Jones protein. This is the position where the V- and J-gene segments join. The J-region of Bence-Jones protein Mev. exhibits some marked differences to the five J-regions recently established by nucleic acid sequencing. This suggests, that there must be considerable polymorphism in human kappa-J-genes. The amyloid fibril protein from the same patient (A Mev.) has also been sequenced up to Position 27. It was found to be identical to the sequence of Bence-Jones protein Mev. commencing with aspartic acid. The molecular mass of the amyloid fibril protein was found to be between 11 000 and 12 000 Da as estimated by gelfiltration and dodecyl sulfate-polyacrylamide electrophoresis.


Subject(s)
Bence Jones Protein , Binding Sites, Antibody , Immunoglobulin Light Chains , Immunoglobulin Variable Region , Immunoglobulin kappa-Chains , Amino Acid Sequence , Endopeptidases , Humans , Immunoglobulin Allotypes/genetics , Multiple Myeloma/immunology , Peptide Fragments/analysis , Trypsin
20.
Biochem Biophys Res Commun ; 194(3): 1427-34, 1993 Aug 16.
Article in English | MEDLINE | ID: mdl-8352801

ABSTRACT

The putative precursor molecule of a human AL type amyloid fibril protein was isolated from an ultrafiltrate after hemofiltration. Subsequent separation of this protein was achieved by high performance liquid chromatography (HPLC) after reduction and carboxymethylation of the disulfide bonds. The protein was separated into several fractions which were further analyzed by automatic amino acid sequence determination. It was deduced from the sequence data that the precursor molecule is an immunoglobulin L-chain of the lambda-type. The V-region of this protein is most closely related to the proteins of subgroup II. Internal splits occurred in the molecule after lysine residues in positions 110, 129 and 179. The predominant fragment commences with either serine or alanine in position 9 and extends to a serine in position 65 of the V-region. Tryptic peptides generated from the fragments cover nearly the entire V- and C-region of the L-chain, with the exception of positions 1-8, from which no peptide has been isolated.


Subject(s)
Amyloid beta-Peptides/biosynthesis , Immunoglobulin Light Chains/metabolism , Immunoglobulin Variable Region/metabolism , Immunoglobulin gamma-Chains/metabolism , Protein Precursors/metabolism , Amino Acid Sequence , Humans , Immunoglobulin Light Chains/chemistry , Immunoglobulin Light Chains/isolation & purification , Immunoglobulin Variable Region/chemistry , Immunoglobulin gamma-Chains/chemistry , Immunoglobulin gamma-Chains/isolation & purification , Molecular Sequence Data , Protein Precursors/chemistry , Renal Insufficiency/metabolism , Sequence Homology, Amino Acid
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