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J Schaller

Publications and source records attributed to J Schaller.

At least 91 records · Page 5Linked to original sources
PubMed1991

HLA in bullous pemphigoid. The probable role of HLA-B7 as a marker for poor responders to immunosuppressive therapy.

The frequency of HLA-class I and DR antigen frequencies were studied in 38 (class I) and 19 (DR) patients with bullous pemphigoid, respectively, and compared with controls. There was no important difference in the frequency of HLA-A,B,C, and DR antigens between patients and controls. An increase in the HLA-B7 frequency in poor responders to immunosuppressants (50% vs. 27% in the control group and vs. 13% in the group of all patients) was noticed, and the possible role of this antigen as a marker for poor responders to therapy was suggested.

Aged↗
PubMed1991

Complete amino acid sequence of equine miniplasminogen.

The complete amino acid sequence of equine miniplasminogen (Mr 37,132, 338 residues) was determined with the aid of fragments obtained by cleavage with 2-(2-nitrophenylsulfenyl)-3-methyl-3'-bromoindolenine, cyanogen bromide or clostripain. The fragments were aligned with overlapping sequences. Sequence comparison with other species gave identities in the range of 76% (bovine) and 81% (canine), indicating the presence of the same structural and functional domains as in the other species. Sequence comparison of different miniplasminogens showed that positions 49 (Arg), 83 (Arg) and 161 (Ser) may play a role in the interaction between plasminogen and streptokinase.

Amino Acid Sequence↗
PubMed1990

MP38 contains the membrane-embedded domain of the lens fiber gap junction protein MP70.

A 70-kDa lens membrane polypeptide (MP70) is a specific component of the fiber gap junctions. The C-terminal portion of MP70 is removed by age-related proteolytic processing, leaving an N-terminal 38-kDa polypeptide (MP38) in the membrane. Membrane association and topology of MP70 and of its processed form MP38 have been studied by hydrophobic labeling with 3-(trifluoromethyl)-3-(m-[125I]iodophenyl)diazirine and phenyl isothio[14C]cyanate. Membrane-embedded segments have been identified. They are localized in the N-terminal 30-kDa portion of MP70 and MP38. The C-terminal 40-kDa portion of MP70 appears to be exposed entirely at the cytoplasmic side of the junctional membranes. Hence, potentially poreforming peptide segments in the MP70 molecule are conserved upon age-related processing to MP38.

Amino Acid Sequence↗
PubMed1990

Interleukin-2 receptor expression and interleukin-2 production in bullous pemphigoid.

Expression of interleukin-2 (IL2) receptors was studied on peripheral blood lymphocytes (PBLs) in 25 patients with bullous pemphigoid. Analysis was carried out by flow cytometry. Without immunosuppressive therapy expression of IL2 receptors only on T cells (CD5) was significantly increased as shown by double staining (11.9% +/- 7.8% vs 2.1% +/- 1% in controls). After 2-3 weeks under immunosuppressive treatment with prednisolone and azathioprine, however, BP lymphocytes did not exhibit any IL2 receptors. PBLs of 18 BP patients showed an increase in IL2 production (1027.4 +/- 670.5 U/ml vs 270 +/- 100 U/ml in controls) during the acute stage of the disease after stimulation with phytohaemagglutinin (PHA)/phorbol myristate acetate (PMA). On the contrary, IL2 production of the same cells in five patients was only in the lowest range of control values after PHA stimulation without PMA (12.5 +/- 29.6 U/ml vs 40 +/- 20 U/ml in controls). Under treatment with immunosuppressants the IL2 production normalized after PHA/PMA stimulation and slightly decreased following PHA stimulation. From these results we conclude that a T-cell activation via activation antigens, as IL2 receptors, and the production of the specific ligand, IL2, may play a role in the pathogenesis of bullous pemphigoid, especially in the earliest stages, and serve as a marker of disease activity.

Aged↗
PubMed1990

Changes in muscarinic acetylcholine receptor binding in skin slices of cholinergic urticaria.

Muscarinic acetylcholine receptors were studied in slices of unaffected skin and in lymphocyte membranes from 3 patients with cholinergic urticaria and 5 healthy subjects using receptor autoradiography and the radioligand [3H]quinuclidinyl benzilate binding technique. Autoradiography revealed that muscarinic acetylcholine receptors were located in regions with sweat glands. The distribution of receptors did not differ qualitatively between patients and controls. However, the maximum number of muscarinic acetylcholine receptors was reduced in skin from patients with cholinergic urticaria, by 44% as compared with the controls, whereas the binding affinity was not affected. Muscarinic cholinergic binding in lymphocyte membrane fractions obtained from patients with cholinergic urticaria did not differ statistically from that of healthy control persons.

Acetylcholine↗
PubMed1990

[A simple method for separating fresh and cryopreserved human sperm using dextran-visotrast density gradient centrifugation].

A procedure for the separation of fresh and cryopreserved human spermatozoa is presented, compared with the Ficoll method according to Harrison [7] and clinically tested. The principle includes a filtration through glass wool and a gradient centrifugation. The gradient medium consists of Ca2(+)-free buffer, Dextran "70" and Visotrast, a radio-opaque medium. The sperm concentration, the sperm-migration-index and the sperm morphology checked by FACS 440 corresponds to the results of the Ficoll-method described by Harrison [7]. Furthermore, our method is usable for semen samples after adding of a cryoprotective medium with egg yolk and glycerol. An improvement of the chance of conception after artificial insemination by husband (AIH) by our method could not be found up to now.

Centrifugation, Density Gradient↗
PubMed1990

[Characterization of lymphocytic infiltrate cells in bullous pemphigoid and pemphigus vulgaris].

By means of monoclonal antibodies (mab) and alkaline phosphatase anti-alkaline-phosphatase (APAAP) technique, the distribution and characteristics of lymphocytic infiltrates were studied in biopsies from 15 patients with bullous pemphigoid (b.P.) and 5 patients with pemphigus vulgaris (P.v.). The biopsies were obtained from freshly developed blisters along with perilesional tissue. The lymphocytic infiltrates in b.P. as well as in P.v. were located in the area of the fresh lesions and consisted almost exclusively of T cells (CD3 positive lymphocytes). In b.P., the discrepancy between a decreased number of CD2 positive lymphocytes (10-20%) and markedly higher number of CD3 staining cells (50-60% of all infiltrate cells) was striking. The characterization of the T cell subpopulations in both dermatoses showed mainly T helper cell infiltrates (CD4), while only up to 10% of T suppressor cells (CD8) were detected. CD45R positive (CD4+/CD45R+: suppression inducing) as well as CD29-positive (CD4+CD29+: cells which provide help for antibody production) T-cell subpopulations were detected in both dermatoses particularly adjacent to blister in up to 10% of the cell infiltrates. Epidermal staining with CD29 mab in b.P. up to the stratum spinosum and in P.v. within intraepidermal blisters was detected. By means of CD19 and CD21 mab B lymphocytes were minimal. Perivascular individual cell staining occurred with CD7 CD16, CD56 and CD57 mab (K/NK cells) in b.P. as well as in P.v. patients. The predominance in T cell infiltrates, particularly T helper cells, suggests the role of cellular immune mechanism in the pathogenesis of these diseases, in b.P. the CD2 antigen (SE receptor) appears to be of particular importance.

B-Lymphocyte Subsets↗
PubMed1989

Neonatal imitation of tongue protrusion and mouth opening: methodological aspects and evidence of early individual differences.

The present work examines imitation of mouth opening and tongue protrusion in 32 full-term infants at three different occasions: When the infants are two to three days, three weeks, and three months old. The analysis focuses (1) on individual differences in imitative behaviour and (2) on how to operationalize the infants' responses. The overall group analysis revealed that imitation of tongue protrusion was statistically significant for both two- to three-day-old and three-week-old infants but not when the children had become three months old. No statistically significant effect was observed for imitation of mouth opening. Two different imitation indexes were constructed in order to assess individual differences in early imitative behaviour. Results show that short-term stability in imitative tendencies exists between the first and second observation. The results further reveal that methodological factors must be seriously considered when studying neonatal imitation: the overall imitation found for tongue protrusion is demonstrated to be dependent on how the infants' responses are coded.

Female↗
PubMed1989

[Expression of leukocyte antigens in human sperm].

The expression of leukocyte antigens on human ejaculated spermatozoa and lymphocytes was compared by means of the immunofluorescence technique and monoclonal antibodies against anti-HLA class I (pan-HLA-A,B,C) and class II (DR, DR/DP). Lymphocytes showed specific fluorescence phenomena after incubation with the antibodies. However, in the case of spermatozoa no immunofluorescent labeling was detected. Modifications of the method of sperm preparation (Ficoll centrifugation, swim-up technique, addition of azide, fetal calf serum or benzamidinchloride) did not lead to different results. We were not able to find HLA-antigen expression on fresh human spermatozoa using immunofluorescence.

Epitopes↗
PubMed1989

[The behavior of membrane receptors of peripheral blood lymphocytes in bullous pemphigoid].

In 35 patients with bullous pemphigoid (BP) various parameters of the cellular immune system were studied. It was shown that the average 29% decrease in the number rosette-forming lymphocytes in sheep red blood cells is converted by the immune complexes and by a second serum factor in the acute stage of BP that has not yet been characterized precisely. These changes were reversible in patients who were placed on immunosuppressants. Obviously, this mechanism is partly due to the binding of immune complexes via Fc receptors on T-lymphocytes and is consequently due to the steral blocking of sheep erythrocyte receptors. No decrease in the number of T-cells was found by means of monoclonal antibodies (CD2, CD3), and the number of suppressor cells was also normal (CD8). On the other hand, the number of T-helper cells increased by an average of 15% (CD4). In addition, in the acute stage, there is a significant increase in the number of activation antigen Tac (CD25) and DR-bearing lymphocytes: 29% and 37% respectively (the normal values are 2% and 11%, respectively). Double staining permitted the phenotype of activated lymphocytes to be detected within the T-cells and the T-helper cell subpopulation, respectively. The number of activated T-helper cells correlates with the disease activity, and from that point it seems to be useful as a marker of activity in follow-up studies.

Aged↗
PubMed1989

Complete amino acid sequence of canine miniplasminogen.

The complete amino acid sequence of canine miniplasminogen (Mr 36,678, 333 residues) was determined with the aid of fragments obtained by cleavage with BNPS-skatole, cyanogen bromide or clostripain. The fragments were aligned with overlapping sequences. Sequence comparison with miniplasminogens of other species gave identities in the range of 80% (bovine) and 88% (human), indicating the presence of the same structural and functional domains as in the other species. Sequence comparison of different miniplasminogens showed that plasminogens of species activated by streptokinase have identical residues in positions 49, 83 and 161 of the plasmin light chain. The triad of these amino acids may represent at least one of eventually several prerequisites for the interaction and activation of plasminogen with streptokinase.

Amino Acid Sequence↗
PubMed1989

[HLA-A, B, C phenotype frequencies in progressive systemic scleroderma].

In 41 patients suffering from progressive systemic sclerosis (PSS) the phenotype frequencies of 28 HLA-A, B, C antigens were determined. Compared to 2947 blood donors the PSS patients exhibited an increase in the HLA-B8 frequency (37% versus 19%). This difference revealed to be not significant after the correction according to the number of antigens tested. The same was with the increase in the frequency of HLA-B5, B13, B27, Cw2 and the decrease in the frequency of HLA-A2, B12, B14, B15, B4 and Cw3. The results were compared with the data reported in the literature. Additionally, there were no differences when compared the diffuse PSS with the acral form and CREST, respectively.

Adolescent↗
PubMed1988

The N- and O-linked carbohydrate chains of human, bovine and porcine plasminogen. Species specificity in relation to sialylation and fucosylation patterns.

The structures of the N- and O-glycans of human, bovine and porcine plasminogen were determined by 500-MHz 1H-NMR spectroscopy. The N-glycans of all three species proved to be of the N-acetyllactosamine type differing from one another with respect to the sialylation and fucosylation patterns. In the N-glycan of human plasminogen the two antennae are sialylated with N-acetylneuraminic acid (NeuAc), whereas in the bovine counterpart both branches carry significant amounts of N-glycolylneuraminic acid (NeuGc). In porcine plasminogen the sialic acid is mainly NeuAc; the Man alpha 1----6 branch, however, is only partially sialylated. In addition, the porcine N-glycan is fucosylated to about 80% in alpha 1----6 linkage to the GlcNAc-1 residue. The O-glycans of the three species possess an identical Gal beta 1----3GalNAc core which is alpha 2----3 sialylated with NeuAc at Gal. The disialylated form, which is also present in all three species, has an additional NeuAc residue in alpha 2----6 linkage to GalNAc. Mono- and disialylated forms occur in different molar ratios in the different plasminogens: 80:20 in human, 70:30 in bovine and 50:50 in porcine. This study on the carbohydrate moiety of these three plasminogens reveals species specificity in terms of various types of microheterogeneities.

Animals↗
PubMed1988

Lymphocytotoxic autoantibodies in progressive systemic sclerosis.

In 53 patients with progressive systemic sclerosis (PSS) the lymphocytotoxic activity of their serum was measured in a microlymphocytotoxicity assay. In 21 of the 53 patients the test reacted distinctly positively in the heterologous system, and in 9 of these 21 also in the autologous system. After preparation of the immunoglobulins from these positive sera, whole cytotoxic activity was detected only in the IgM fraction but not in the IgG fraction. When using prepared T lymphocytes as target cells in the microlymphocytotoxicity test, the cytotoxic activity of the positive PSS sera showed itself to be directed against this lymphocyte population. Further analysis using the Western-blot technique showed that the IgM autoantibody in PSS sera reacted with the cell surface of CD4+ lymphocytes. The cross reactivity with extractable nuclear antigens was rather improbable. These results suggest that lymphocytotoxic autoantibodies may play a role in immunological disturbances in PSS.

Adolescent↗
PubMed1988

Complete amino acid sequence of human plasma Zn-alpha 2-glycoprotein and its homology to histocompatibility antigens.

In the present study the complete amino acid sequence of human plasma Zn-alpha 2-glycoprotein was determined. This protein whose biological function is unknown consists of a single polypeptide chain of 276 amino acid residues including 8 tryptophan residues and has a pyroglutamyl residue at the amino terminus. The location of the two disulfide bonds in the polypeptide chain was also established. The three glycans, whose structure was elucidated with the aid of 500 MHz 1H NMR spectroscopy, were sialylated N-biantennas. The molecular weight calculated from the polypeptide and carbohydrate structure is 38,478, which is close to the reported value of approximately equal to 41,000 based on physicochemical measurements. The predicted secondary structure appeared to be comprised of 23% alpha-helix, 27% beta-sheet, and 22% beta-turns. The three N-glycans were found to be located in beta-turn regions. An unexpected finding was made by computer analysis of the sequence data; this revealed that Zn-alpha 2-glycoprotein is closely related to antigens of the major histocompatibility complex in amino acid sequence and in domain structure. There was an unusually high degree of sequence homology with the alpha chains of class I histocompatibility antigens. Moreover, this plasma protein was shown to be a member of the immunoglobulin gene superfamily. Zn-alpha 2-glycoprotein appears to be a truncated secretory major histocompatibility complex-related molecule, and it may have a role in the expression of the immune response.

Amino Acid Sequence↗
PubMed1988

Structural aspects of the plasminogen of various species.

The N-terminal amino acid sequence of equine, ovine, canine, goat and rabbit plasminogen were determined and compared with those already known of the human, bovine, porcine and feline molecule. Furthermore, the kringle 4 domains of equine, ovine, canine and goat plasminogen, prepared by limited cleavage with elastase, were sequenced and compared with the known species of human, bovine, porcine and chicken plasminogen. Homology with the human kringle 4 ranges between 73% (chicken) and 90% (bovine). Comparison of sequences, fragmentation patterns with elastase and adsorption on lysine-Bio-Gel suggests the same structural and functional domains in the animal species as in human plasminogen.

Amino Acid Sequence↗