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Biomedical subjects

F Hiepe

Publications and source records attributed to F Hiepe.

At least 109 records · Page 6Linked to original sources
PubMed1990

Binding of C1q and DNA to support materials by means of a new coupling procedure.

Since several years matrix-bound biologically active substances are widely used in biosciences, biotechnology and medicine. We are presenting a simple and inexpensive activation procedure for support materials which allows stable binding of C1q and DNA. We could not found a remarkable leakage of the bound ligands. In connection with the good biocompatibility of our procedure, both are important for the application in extracorporeal immunoadsorption. The method is technologically simple and represents an alternative to the activation methods applied so far.

Biocompatible Materials↗
PubMed1990

Development of a DNA-adsorbent for the specific removal of anti-DNA autoantibodies in systemic lupus erythematosus (SLE).

Autoantibodies against DNA are of primary importance for the diagnosis and pathogenesis of systemic lupus erythematousus (SLE). The level of anti-DNA antibodies correlates well with the disease activity and renal involvement. In such patients the removal of anti-DNA antibodies from plasma may lead to a clinical improvement. For this reason an adsorbent was made by covalent coupling of calf thymus DNA to a solid support based on ethylene dimethacrylate cross-linked hydroxethyl methacrylate. Up to 2.5 mg of DNA were immobolized to 1 ml of the support activated chemically by aminosilane and glutaraldehyde. The incubation of 40 ml of SLE plasma with 1 ml of the adsorbent resulted in a 50% decline in anti-DNA activity. There was no release of immobilized P-32-DNA into the plasma. Biocompatibility, sterilisation, and reapplication (without loss of binding capacity) of the adsorbent could be demonstrated. We concluded that the adsorbent may be suitable for treatment.

Autoantibodies↗
PubMed1990

Development of a C1q-adsorbent for the selective removal of circulating immune complexes.

In body fluids circulating immune complexes possess a substantial pathogenic effect on a variety of diseases. Thus it seems to be reasonable to influence the pathogenic mechanism of such diseases by removing the circulating immune complexes out of the body fluids. The selective adsorbent for binding immune complexes were developed as possible alternative of plasmapheresis for specific removal of immune complexes out of the blood plasma. The principle is based on the biospecific binding of immune complexes to C1q that is immobilized by a covalent binding to different solid phases. Thus: so bound immune complexes can be separated by detaching the solid phases. The adsorbent may be regenerated by non-denaturated media and can be used manyfold. This adsorbent has a high biocompatibility and offers the possibility for clinical use.

Antigen-Antibody Complex↗
PubMed1990

Multireactive human monoclonal antibodies.

Human monoclonal antibodies were tested using different immunochemical procedures for their reactivity with various antigens. The great majority of human monoclonal IgM antibodies (15 out of 24) turned out to bind to a whole series of recognized antigens (DNA, keratin, tetanus toxin, ricin etc.). The specificity of these reactions was detected by competitive assays. For some antibodies a simultaneous reaction with two antigens could be demonstrated by capture bridge technique. IgG antibodies also turned out to be multireactive, but not to the same extent (range of antigens much smaller, only 5-6 out of 53).

Antibodies, Antinuclear↗
PubMed1990

[Chemiluminescence measurements of bronchoalveolar lavage cells in patients with collagenosis].

The purpose of the study was to determine the role of reactive oxygen metabolites in the pathogenesis of interstitial lung involvement in 13 patients with collagen vascular diseases (CVD) in comparison with 10 control subjects. The cellular activity of bronchoalveolar lavage (BAL) cells was measured by means of chemiluminescence (CL), spontaneously and after challenge of the cells with opsonized zymosan (simultaneously luminol- and lucigenin-dependent). The findings show an increase of the spontaneous and stimulated CL of BAL cells in CVD, more pronounced in luminol-dependent CL. The luminol-dependent CL correlates with neutrophils in BAL cell differentiation. The results suggest that reactive oxygen metabolites take part in interstitial lung involvement in patients with CVD. Therefore the measurement CL of BAL cells is useful in addition to BAL cell differentiation in diagnostic of interstitial lung involvement in CVD.

Bronchoalveolar Lavage Fluid↗
PubMed1989

[Circulating immune complexes in patients with mouth mucosa carcinoma].

In 76 patients with untreated, advanced carcinomas of the oro-facial region the immune complex titer in the serum was determined by the C1q binding test. The determination of the immune complexes, accompanying the therapy, was carried out before onset of therapy and after surgical, combined radiosurgical and radiation therapy respectively. Immune complex values did not differ significantly before and after therapy and were of no value regarding the evaluation of the effectiveness of therapeutic measures.

Antigen-Antibody Complex↗
PubMed1989

Prevention of graft-vs-host reaction induced immunodeficiency by treatment with splenopentin (DAc-SP5).

Early experiments had shown that splenopentin, the active part of the splenic hormone splenin, stimulates the differentiation of virgin B- and T-lymphocytes and significantly enhanced the reconstitution of immune reactions after immune suppression. The present study investigates the influence of splenopentin on the course of the graft-vs-host reaction (GVHR). The experimental model used were adult hybrid mice which received intravenously parental spleen cells. During the GVHR which has an chronical course in the strain combinations used a short stimulatory phase is followed by a long-lasting immunosuppression detected by antibody formation against sheep erythrocytes. Furthermore, the splenomegaly in the first weeks after spleen cell injection changed to a drastic decrease of the spleen weight up to strongly beyond normal values. Continuous treatment with splenopentin significantly prevented both symptoms of the GVHR: The suppression of the antibody formation was diminished widely, and no loss of spleen weight occurred. Furthermore, during the stimulatory phase anti-DNA-autoantibodies were produced in the untreated animals, while the splenopentin therapy prevented this reaction. During the further course of the experiment no increase of autoantibody production was detected later on.

Animals↗
PubMed1988

Establishment of human Ig producing heterohybridomas by fusion of mouse myeloma cells with human lymphocytes derived from peripheral blood, bone marrow, spleen, lymph node, and synovial fluid. Effect of polyclonal prestimulation and cryopreservation.

50 fusion experiments were carried out to analyse heterohybridization efficiencies on mouse myeloma cells of the P3 X63 Ag8/653 line with human lymphocytes derived from peripheral blood, bone marrow, lymph node, spleen or synovial fluid. We found higher yields of growing and human Ig-producing hybridoma lines when lymphocytes from spleen or lymph node were fused. Although primary hybridomas could be established from fusions with bone marrow-derived cells, only in nine out of 1616 initially seeded wells was Ig production registered. Four fusions using immune cells from synovial fluid were made without success. Independently of the source of lymphocytes pokeweed mitogen (PWM) prestimulation had no enhancing effect on the percentage of wells with cell growth and this did not alter the IgM:IgG ratio in primary hybridomas (9:1), although cells from all compartments used here (with the exception of bone marrow cells) could be stimulated with PWM to produce both IgG and IgM in cultures. Cryopreserved lymphocytes from different sources could be used for fusions with comparable results registered for the fresh material.

Animals↗
PubMed1988

A myelopeptide from unstimulated bone marrow cells with immunomodulatory activity in lymphocyte cultures from healthy donors and patients with hypogammaglobulinemia and active lupus erythematosus.

A myelopeptide (SAP) was derived from culture supernatants of unstimulated animal bone marrow. SAP consists of a group of peptides with a molecular weight of about 2000 D, having a broad variety of biological activities. Testing immunoregulatory properties of the purified factor Petrov, Mickhailova & Zacharova [(1971). Immunoglobin synthesis in syngenic cells of different lymphoid tissues. J. Immun., 106 1086-1089] found enhanced antibody production in mice (SAP-stimulator of antibody production). We show here that the substance could induce expression of activation markers on human lymphocytes (4F2, HLA-class II antigens, thermostable SE rosette formation) and potentiate their appearance in combination with mitogens (PWM, PHA, Con A). Although SAP was not mitogenic for itself, it enhanced lectin-induced 3H-thymidine incorporation and T-cell-dependent B-cell differentiation in a dose-dependent manner. The factor was able to reconstitute disturbed PWM-driven Ig synthesis in lymphocyte cultures derived from two patients with hypogammaglobulinemia and a healthy non-responder to PWM. On the other side, SAP potentiated the inhibitory activity of PWM on elevated spontaneous IgG secretion in cultures derived from patients with active SLE. Findings of this study indicate immunomodulatory capacity of SAP on human peripheral blood lymphocytes possible via T-cell activation. The results suggest a potential therapeutic application of SAP in patients with disturbances in the T-dependent B-cell differentiation.

Agammaglobulinemia↗
PubMed1987

The influence of interferon-gamma, interleukin-2, prostaglandin E2, and cyclosporine on the polyclonal and anti-DNA antibody secretion in lymphocyte cultures derived from patients with systemic lupus erythematosus.

The influence of various immunoregulatory substances was studied in lymphocyte cultures derived from patients suffering from systemic lupus erythematosus (SLE) by using the model of spontaneous secretion of polyclonal immunoglobulin G (IgG)/immunoglobulin M (IgM) and anti-DNA autoantibodies. Compared with healthy donors, lymphocytes derived from patients with active SLE disease showed an elevated secretion of total IgG as well as anti-DNA-IgG in vitro, which was associated with an increase in the proportion of activated (HLA-class II +) T cells in their peripheral blood. Recombinant interferon-gamma increases the total IgG/IgM as well as anti-DNA-IgG/IgM secretion, which suggests that it has a possible role in the pathogenesis of SLE disease. Recombinant interleukin-2 and prostaglandin E2 normalize the high, spontaneous total IgG secretion, but elevate anti-DNA-IgG/IgM secretion. These results suggest that autoreactive B-cell clones are regulated differently in SLE patients. Cyclosporine inhibits total IgG/IgM secretion in all patients and anti-DNA-IgG/IgM secretion in six of eight patients. The possible therapeutic use of such immunomodulatory substances in SLE disease is discussed.

Adolescent↗
PubMed1986

Extracts from Sarcocystis gigantea macrocysts are mitogenic for human blood lymphocytes.

Extracts were prepared from macrocysts of Sarcocystis gigantea, an animal parasite, by sonication and high speed centrifugation. Mononuclear cells were obtained from the blood of 14 adults and 5 newborns and used for transformation assays. Addition of Sarcocystis extracts (equivalent to 400 micrograms protein/ml) to these cells increased the lymphocyte proliferation approximately 71 fold over the background. The control with Pokeweed mitogen (5 micrograms/ml) gave a stimulation index of 58. There was no difference in the response to the Sarcocystis extract between the lymphocytes of adults and those of newborns. This findings show that the effect of the extract is mitogenic and not due an anamnestic reaction.

Adult↗
PubMed1986

A sensitive and class specific solid phase enzyme immunoassay for anti-DNA autoantibodies in supernatants of lymphocyte cultures and human hybridomas.

A solid phase enzyme immunoassay using methylated bovine serum albumin (BSA)-precoated and DNA-coated microtiter plates was developed for the detection of IgG and IgM anti-DNA autoantibodies in the supernatants of lymphocyte cultures and hybridomas. In patients with systemic lupus erythematosus (SLE) the significantly raised IgG anti-DNA antibody synthesis indicates that preactivated anti-DNA clones circulate in the peripheral blood. This was associated with the detection of anti-DNA antibodies in the sera. The screening of 53 supernatants from human x mouse hybridomas showed an antibody to denatured DNA in 16 supernatants.

Antibodies, Monoclonal↗