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Biomedical subjects

H Ambrosius

Publications and source records attributed to H Ambrosius.

At least 73 records · Page 4Linked to original sources
PubMed1981

[Suppressive effects of 5-bromuracile and 5-bromuracile-epsilon-aminocaproic acid on the humoral anti-sheep erythrocyte immune response of mice in vivo and in vitro (author's transl)].

4 x 30 mg/kg 5-bromuracile (5-BrU) - injected shortly after the antigen once per day - suppress the development of direct plaque forming cells (PFC) in the spleen of immunized mice on the 4th day of the primary reaction weakly. 5 higher doses epsilon-aminocapronic acid (ACA) were not immunosuppressive, but those of 5-BrU-ACA. The immunosuppression was of short time, 6 days later equal direct PFCs were found in the spleens of experimental and control groups. 5 x 150 mg/kg 5-BrU-ACA or ACA decreased the formation of indirect PFCs on the 10th day of immune response. In vivo 5-BrU and 5-BrU-ACA inhibited the development of non or specific stimulated spleen cells to direct PFCs only in partially cytotoxic concentrations of 5 times 10(-4) Mol.

Aminocaproates↗
PubMed1981

[Immunological investigations of patients after thermic injury (author's transl)].

A burn toxin, which is important for the manifestation of clinical and septical processes during the burn disease, was isolated from burned skin of mice. Using this antigen we have studied the immunological reactions against burn toxin in 10 patients following thermic trauma. We determined the specific antibodies against the burn toxin by means of the passive hemagglutination test, the level of IgM, IgG and IgA in the serum using Mancini-immunodiffusion, the burn toxin binding cells by means of the antigen specific rosette technique and the cell-mediate immunity using the macrophage electrophoretic mobility test (MEM-test). A rise of the burn toxin-specific cells could be observed with maximum at day 4 and a second peak at day 10 and cell mediated immunity between day 10 and day 15. The titer of specific antibodies increased, most following an initial decrease, after day 6, a correlation seemed to exist between this titer and the level of immunoglobulins in the serum.

Antibody Formation↗
PubMed1981

Macrophage adherence inhibition assay: measurements of adherent cells by the TV image analysis system Densitron.

A procedure is described to automate the cell counting step in the indirect macrophage adherence inhibition assay using the TV image analysis system Densitron. Comparison of the results of direct visual counting and of Densitron measurements of the adherent cells in the haemocytometer chamber indicates the qualification on principle of Densitron to substitute the time consuming and exerting visual counting procedure.

Animals↗
PubMed1981

Detection of a monoclonal human myeloma protein of IgM and IgG class by carp anti-idiotypic sera.

In the Patient St. with a Morbus Waldenström macroglobulinemia a double paraproteinemia could be detected. Besides the IgM myeloma protein an IgG myeloma protein was identified during the clinical course. A strong cross reactivity between the IgM and the IgG myeloma proteins was shown using anti-idiotypic antisera. This is an indirect indication for a common precursor cell clone of the IgM- and IgG-myeloma protein producing cells. The anti-idiotypic antisera were made in carp. The high specificity of these antisera could be confirmed by inhibition assays. The double paraproteinemia has been proved to be convenient model for testing the idiotypic specificity of anti-Id antisera of carp.

Animals↗
PubMed1981

[Alpha 1-antitrypsin: production and binding of in vitro stimulated peripheral blood lymphocytes].

Three day cultures of human peripheral blood lymphocytes (PBL) contain significant numbers of lymphoblasts binding 125I-alpha 1-AT as well as those with membrane-associated alpha 1-AT detectable by immunofluorescence. Co-cultivation of PBL with T cell mitogens leads to the appearance of lymphoblasts with membrane-associated alpha 1-AT while B cell mitogens induce lymphoblasts with a binding capacity for 125I-alpha 1-AT. It could be shown that unstimulated lymphocytes neither have membrane-associated alpha 1-AT nor possess a binding capacity for it. The highest number of lymphoblasts with membrane-associated alpha 1-AT was found in Con A stimulated cultures as revealed by indirect immunofluorescence. By contrast, PHA or PPD stimulated cultures contained much less such cells of lower fluorescence intensity. Co-cultivation of PBL with the B cell mitogens LPS and rabbit-anti-human gammaglobulin-IgG-F(ab')2 induced lymphoblasts with a clear binding capacity for 125I-alpha 1-AT, while dextran-sulphate had no effect. A possible regulative role of alpha 1-AT in the immune response is discussed.

Humans↗
PubMed1981

Comparison of the hemocytometer and tube modifications of the leukocyte adherence inhibition assay -- II. Application of both modifications for detection of anti-tumor immunity in man.

The hemocytometer and the tube modifications of the leukocyte adherence inhibition (LAI) assay were compared under identical experimental conditions in patients with carcinoma of the larynx. In the direct test, both modifications showed adherence inhibition if patients peripheral blood leukocytes (PBL) were incubated with a larynx cancer antigen preparation. Cell-free supernatants obtained by cocultivation of patients PBL with the antigenic extract yielded positive results only in the hemocytometer modification. Those supernatants inhibited the adherence of both normal human PBL and guinea pig peritoneal cells. Human encephalitogenic protein used as antigenic preparation in both direct and indirect hemocytometer modifications caused changes in adherence too. The presented results confirm the opinion that the hemocytometer and tube LAI assays base on different mechanisms.

Adult↗
PubMed1981

Detection of anti-tumor immunity in man by the indirect macrophage adherence inhibition assay using guinea pig peritoneal cells as indicator cells.

Supernatants obtained after incubation of tumor patient lymphocytes with the homologous tumor-associated antigen (TAA) elicit adherence inhibition in normal guinea pig peritoneal cells. From 37 tested patients with different carcinomas, the supernatants of 30 caused more than 10 per cent adherence inhibition (breast cancer 11/11, lung cancer 7/8, colon cancer 6/7, stomach cancer 6/11). Besides 40 healthy blood donors were tested to a panel of TAA. There was a reactivity more than 10 per cent only in 2 cases. The supernatants of 14 patients with nonmalignant disorders produced adherence inhibition more than 10 per cent in 2 cases. By incubation of tumor patient lymphocytes with the human encephalitogenic protein the supernatants of 19/27 patients elicited a positive reaction. The results suggest that anti-tumor immunity can be detected in an indirect heterologous adherence inhibition system.

Animals↗
PubMed1980

[Cooperation of B- and T-lymphocytes of the human in vitro and in vivo].

It is reported on the experimental proofs for the existence of a cooperation of different populations of lymphocytes in man. Regulatory lymphocytes play a part in the regulation of the synthesis of immunoglobulins by polyclonally stimulated B-lymphocytes, in the generation of killer-T-cells and in the regulation of the DNA-synthesis by mitogenically stimulated T- and B-cells. Typical helper- and suppressor-effects may be proved. Disturbances of lymphocytic interactions may be a cause for the development of immune deficiency diseases. It is very probable that also in several chronic infections a dysfunction of regulatory T-lymphocytes is present.

Autoimmune Diseases↗
PubMed1980

[Evolutionary origin of the T-lymphocyte receptor. II. Production and partial characterization of antisera to the immunoglobulin-like cell membrane protein from thymocytes of the carp].

An immunoglobulin-like protein from Triton X-100 solubilized cell surface proteins from thymocytes can be isolated by specific precipitation using anti-IgM antibodies. Immunizing rabbits with those immune complexes we succeeded to elicit anti-thymocyte mIg sera reacting with both thymocyte mIg and IgM. SDS-PAGE analysis revealed that anti-IgM and anti-thymocyte mIg sera recognize the same thymocytic surface protein. The cross-reactivity between thymocyte mIg and IgM is caused by protein determinants very similar to each other. Anti-thymocyte mIg sera absorbed with IgM lose their capacity to bind thymocyte mIg. However, following absorption with thymocytes anti-IgM sera still possess amounts of antibodies reacting with humoral IgM.

Animals↗
PubMed1980

[Additive suppressive effect of Freund's complete adjuvant on the specific inhibition of anti-DNP immunoreaction (author's transl)].

Injection of DNP 38-Ficoll in 0,9 per cent saline causes a specific suppression of the secondary anti-DNP reaction in AJ-mice to the same antigen. This suppression is amplified by injection of the tolerogen in Freund's complete adjuvant (FCA) or by simultaneous injection of the tolerogen and FCA. --This additive suppressive effect of FCA is distinctly better if there are used small doses of tolerogen. Possible mechanisms interpreting these results are discussed.

Animals↗
PubMed1980

[Studies on the E rosette test (author's transl)].

The number of T lymphocytes in the peripheral blood of normal subjects and patients with bronchial carcinoma was determined by using the E rosette test. In a comparative study we counted the "total" rosette forming cells and the "active" rosette forming cells using a lymphocytes-sheep red cells-ratio (Ly-SRBC-R) of 1:8 and 1:40. The numbers or rosettes in the two test systems are in correlation with the Ly-SRBC-R despite other differences in the techniques. -A significant difference was determined between normal subjects and patients with the "active" rosette test only with a L-SRBC-R of 1:40. By contrast the values with the L-SRBC-R of 1:8 were not very different between the two groups. -Also the number of "total" rosettes was significantly different between blood donors and carcinoma patients, using the L-SRBC-R. 1:40. -These results are not of direct clinical relevance, because the values of normal subjects and carcinoma patients are overlapping.

Bronchial Neoplasms↗
PubMed1980

[Determination of TAA-binding cells in peripheral blood of breast cancer patients (author's transl)].

Circulating human breast tumor-associated antigen (TAA) specific lymphocytes were detected in breast carcinoma patients by antigen specific rosette technique. About 60 percent of patients with breast cancer showed a positive reaction in our test system, the number of rosettes were considerably increased in comparison to the values of blood donors. Following operation normally the number of TAA specific rosettes decrease, contrary, in all cases with recidives, tested, we found positive test results. There is evidence, that our modification of the specific rosette-technique is suitable for detection of malignomas and can be important for the postoperative control of patients with breast carcinoma.

Antigens, Neoplasm↗