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O BROBERGER

Publications and source records attributed to O BROBERGER.

16 recordsLinked to original sources
PubMed1963

In vitro studies of ulcerative colitis. I. Reactions of patients' serum with human fetal colon cells in tissue cultures.

By means of immunofluorescent methods it has been shown that sera from children with ulcerative colitis contain antibodies which react with fetal colon cells in tissue culture. 5 out of 13 sera from patients reacted positively when tested for staining antibodies while 12 sera from healthy individuals yielded negative results. The specificity of the staining reactions was confirmed by inhibition experiments. The staining capacity of various sera was correlated to their hemagglutinating titer when tested against phenol-water extracts of human colon. The presence of blood group substances of the ABO system on fetal colon cells in tissue culture could be demonstrated by application of fluorescent H agglutinins from eel. Cross-inhibition experiments indicated that the H agglutinins stained colon antigens which were different from those reacting with the antibodies of ulcerative colitis sera. The reactivity of cultured fetal colon cells with the antibodies in ulcerative colitis sera was retained for up to 12 days, with optimal staining at 4 to 5 days. Reactivity with H agglutinins was present for a longer period, sometimes more than 20 days. Although antigen could be shown to be present on fetal colon cells in tissue culture, exposure of the culture, in the presence of fresh guinea pig serum, to sera from patients with ulcerative colitis did not lead to any visible cytotoxic damage. In order to investigate the possible cytotoxic effect of the sera with a more sensitive technique, freshly explanted fetal colon was dispersed by trypsinization and the cells labeled with (32)P-orthophosphate. Subsequently, these cells were exposed to sera, in a final concentration of 30 per cent, from patients or healthy controls in the presence of fresh guinea pig serum (final concentration 15 per cent). Approximately 20 per cent of the cellular isotope was released into the medium within 150 minutes of incubation, but the release was the same in the samples treated either with patients' sera or normal control sera. Thus, under the present conditions, the patients' sera did not exert any specific cytotoxic action on colon cells.

Antibodies↗
PubMed1963

In vitro studies of ulcerative colitis. II. Cytotoxic action of white blood cells from patients on human fetal colon cells.

Freshly isolated fetal human colon cells were labeled with (32)P-orthophosphate or (14)C-amino acids and exposed to white blood cells from children with ulcerative colitis or from healthy controls. Exposure of the colon cells to patients' white cells led to a rapid isotope release, significantly higher than that obtained with normal white cells. After 150 minutes of incubation, 75 per cent of the total isotope present was found in the media of the colitis samples but only 40 per cent in those of the controls. Consistent results were obtained with white blood cells from 14 patients and 18 healthy individuals. Similar results were obtained with either fresh white cells or with white cells aged for 12 to 18 hours and consisting to 60 to 70 per cent of lymphocytes and to 20 to 30 per cent of large mononuclear cells. No specific cytotoxic activity could be conferred onto normal white cells by pretreating them with patients' serum containing antibodies against colon antigen. The cytotoxic action of the patients' white cells was immunologically specific, since no difference from the controls was found in the isotope release when cells from other organs or animals were similarly treated. Preliminary experiments suggested that the patients' white cells could be desensitized by pretreating them with colon extract. For obtaining a significant cytotoxic effect of the patients' white cells, the presence of 10 to 20 per cent of fresh guinea pig or human serum in the incubation medium was required.

Animals↗
PubMed1962

Demonstration of an epithelial antigen in colon by means of fluorescent antibodies from children with ulcerative colitis.

Thirteen sera from children with ulcerative colitis were examined for antibodies reacting with constituents of human colonic tissue by means of immunofluorescent methods. 3 out of 10 sera reacted positively when tested by the direct staining method while 6 out of 13 reacted positively when tested by the indirect method with conjugates of rabbit anti-human gamma globulin. The specificity of the reactions could be confirmed by inhibition tests. 16 sera from healthy children and adults yielded completely negative results. The staining capacity of various sera was correlated to their hemagglutinating titer when they were tested with sheep erythrocytes, coated with phenol-water extract of human colon. Absorption experiments indicated that the stainable antigen was also present in the extracts used for the hemagglutination experiments. In unfixed tissue sections, fluorescent antibodies were adsorbed onto the epithelial cells of the mucosa. Adsorption on epithelial basement membranes could not be demonstrated. Fluorescent H agglutinins, isolated from eel serum, were adsorbed onto the same mucosal structures of human colon (blood group O) as the antibodies in the sera of patients with ulcerative colitis. However, any immunological relationship between H substance and the colonic antigen of ulcerative colitis could be ruled out by cross-inhibition and hemagglutination inhibition experiments. Fluorescent serum from patients with rheumatoid arthritis also stained sections of human colon but the localization of the stainable antigens was different from that visualized with the ulcerative colitis sera. Inhibition experiments indicated that the rheumatoid arthritis serum contained antibodies staining colon antigens different from those reacting with antibodies in the ulcerative colitis sera. Sera from patients with systemic lupus erythematosus or with the nephrotic syndrome, which all hemagglutinated erythrocytes coated with colon extract, did not stain the sections of the colon tissue either because of suboptimal antibody concentration or because of a difference in type or localization of the antigen.

Adult↗
PubMed1959

Autoantibodies in human ulcerative colitis.

Sera from 30 children, suffering from ulcerative colitis, were examined for the presence of antibodies capable of reacting with antigens of normal human tissue. It was possible to demonstrate that most of the sera contained a precipitating and hemagglutinating factor, reacting with a constituent of human colonic tissue. This constituent was obtained, within 1 hour after death, from colonic tissue of newborn babies who had died without feeding. It could also be prepared from fetal tissue. The antigen can be extracted with phenol-water at 65 degrees C. and seems to be a polysaccharide. The precipitating factor in the sera of the patients behaves electrophoretically as a gamma-globulin. Phenol-water extracts from liver and from kidney also reacted positively with the sera from certain patients. There are indications which suggest that the antigen obtained from these tissues is identical with that from colon. Sera from 38 healthy children did not give any reactions with the extracts used. In additional controls, the sera of 32 children with various diseases, all of suspected autoimmune origin, were also tested. A few of these reacted positively with the phenol-water extracts from the organs mentioned above. Most likely, the antigen reacting in these cases is different from that reacting with the antibodies in the sera from patients with ulcerative colitis. The possible role of the antibodies in the pathogenesis of ulcerative colitis and the mechanism of their formation are discussed.

Antigens↗