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Biomedical subjects

O Closs

Publications and source records attributed to O Closs.

At least 55 records · Page 3Linked to original sources
PubMed1980

Comparative studies of antigen 21 in Mycobacterium and Nocardia species: possible taxonomic relationships with Mycobacterium leprae.

Studies of Mycobacterium leprae, Mycobacterium tuberculosis and Nocardia caviae in comparison with each other and with other Mycobacterium and Nocardia species were performed on the basis of antigen 21 intramolecular heterogeneity. Three different antisera were used: rabbit anti-Mycobacterium smegmatis antiserum, rabbit anti-Nocardia asteroides antiserum, and a lepromatous serum pool. With reference to each of the three antiserum sources used the strains were ranked in an order of relatedness or sharing of determinants. The three antisera showed distinctly different antigen 21 antibody specificities reflecting the species origin of the immunogen. The present investigations confirmed that antigen 21 of N. caviae shares determinants with antigens from Mycobacterium strains which were not present in corresponding antigens of all other Nocardia strains tested. M. tuberculosis, as judged by antigen 21 analysis, occupies a position separate from both the slow-growing and the fast-growing mycobacterial clusters in accordance with accepted taxonomic relationships. An interesting possibility of establishing a position for M. leprae in relation to other mycobacterial species was apparent. The order of relatedness among the strains studied went from M. leprae to M. tuberculosis to N. caviae to Mycobacterium avium to Mycobacterium fortuitum, the last two being representatives of the slow-growing and fast-growing mycobacteria. It can therefore be concluded that evidence from antigen 21 analysis indicates that M. leprae is more closely related to M. tuberculosis than to the other strains investigated.

Antigens, Bacterial↗
PubMed1979

The humoral immune response to alpha, beta and gamma crystallins of the human lens.

By radioimmunoassay the occurrence of antibodies against alpha, beta and gamma crystallins was examined in sera from groups of patients with clear lenses, cataracts or lens injuries. In about half of the sera from each group low anti alpha crystallin activity was found. No significant difference in antibody activity was found between the groups. Antibody activity against beta or gamma crystallins was not detected in any of the sera. Four patients with lens damage were followed for 2 years; two of them developed uveitis and showed increasing anti alpha crystallin activity. It is suggested that in man immunological tolerance to lens crystallins is normally present.

Adolescent↗
PubMed1979

Cross-reactions between mycobacteria. II. Crossed immunoelectrophoretic analysis of soluble antigens of BCG and comparison with other mycobacteria.

Cross-reactions between Mycobacterium bovis BCG and various other mycobacteria, Nocardia asteroides, Corynebacterium pyogenes and Listeria monocytogenes were studied by incorporating antibodies against these bacteria in the intermediate gel of a crossed immunoelectrophoretic system with BCG antigen and anti-BCG antibodies. In the BCG reference system forty-four distinct antigenic components were recorded, of which thiryt-three cross-reacted with Mycobacterium tuberculosis, twenty-five with M. avium, twenty-one with M. suvalii, eighteen with M. smegmatis, Fifteen with M. nonchromogenicum, twelve with M. phlei, eight with N. anteroides and two with C. pyogenes, whereas no cross-reaction was detected with L. monocytogenes. The value of the method for characterization of mycobacterial antigens is discussed. A taxonomic system based on this method appears particularly valuable for studies of non-cultivativable mycobacteria such as M. leprae. A majority of twenty-one patients with lepromatous leprosy had anti-BCG antibodies of restricted specificity, affecting only four or five BCG antigens, although one patient had twelve anti-BCG specificities. Most of these antibodies reacted with those BCG antigens that cross-react extensively with other mycobacteria.

Antibodies, Bacterial↗
PubMed1979

Antibody response in rabbits to Mycobacterium bovis BCG.

The specificity of the immune response after immunization with Mycobacterium bovis BCG was studied by crossed immunoelectrophoresis with intermediate gel in a BCG/anti-BCG system, in which the reaction against thirty distinct components of BCG was recorded. After a single injection of total sonicate of 3 mg (dry weight) bacilli, the antibody response was markedly similar in eight rabbits. Th earliest and strongest response was directed against nine components of BCG; all but one of these belonged to the group of thirteen components that cross-react extensively with other mycobacteria. After repeated immunization with sonicate from about 0.8 microgram of BCG bacilli, five components still induced a marked antibody response. All but one of these components are among the most widely cross-reacting BCG components, and the observations made after subsequent challenge with the higher dose of BCG indicate that low-zone tolerance was induced against other components of the bacilli. The implication of these findings concerning formation of anti-mycobacterial antibodies in normal individuals and during mycobacterial infection is discussed.

Animals↗
PubMed1979

Antigenic analysis of Mycobacterium leprae.

About twenty distinct antigenic components have been demonstrated in Mycobacterium leprae (M. leprae) by crossed immunoelectrophoresis against a rabbit antiserum produced by immunization with concentrated M. leprae antigen. This system allows a more detailed analysis of the antigenic relationship between M. leprae and other mycobacteria and a better characterization of the antigenic content of various M leprae preparations than with previously available anstisera of the antigenic content of various M. leprae preparations than with previously available antisera which reacted with far fewer components. The antibody activity in sera of patients with lepromatous leprosy was studied by incorporating the sera into the intermediate gel of the M. leprae reference system. Antibodies were found against only seven of the components. Since those compared are all known to be cross-reacting widely with antigens of other mycobacteria, it is speculated that cross-immunization may influence the antibody response in lepromatous leprosy.

Animals↗
PubMed1979

Cross-reactions between serum proteins and water soluble liver tissue antigens of the nine-banded armadillo (Dasypus novemcinctus Linn.) and man.

Cross-reactions between serum proteins and water soluble liver antigens of the nine-banded armadillo (Dasypus novemcinctus Linn.) and man were studied by crossed immunoelectrophoresis (CIE). Armadillo serum tested with rabbit antiserum against human serum proteins gave twelve components in CIE. Nine of these cross-reacting proteins were identified and showed partial identity with the corresponding human proteins. The electrophoretic mobility of alpha 2-macroglobulin and Gc-globulin differed in the two species. An ultrasonicate of normal armadillo liver gave twenty-eight anodic and eight cathodic components in CIE. By absorption experiments with armadillo serum, twenty of the former and seven of the latter were shown to be liver tissue components. A combination of CIE and crossed-line immunoelectrophoresis (CLIE) revealed the presence of twelve anodic and six cathodic liver tissue components cross-reacting with man. A cathodic armadillo liver antigen called (CALA-17) showed partial identity with that of man both in tandem and fused rocket immunoelectrophoresis. The implications of the findings are discussed in relation to the use of armadillo-grown M. leprae for skin testing and other purposes in man.

Animals↗
PubMed1978

Formation of antibody against Mycobacterium leprae antigen 7 in armadillos.

A radioimmunoassay developed to measure antibody against Mycobacterium leprae antigen 7 in man was applied to the nine-banded armadillo (Dasypus novemcinctus). Normal armadillo sera had low but significant antibody activity in the test. Fourteen of 17 armadillos with systemic mycobacterial infection after inoculation with M. leprae showed increased antibody activity in the assay, and in some instances the activity was higher than in a pool of sera from patients with lepromatous leprosy. Crossed immunoelectrophoresis with armadillo serum in the intermediate gel revealed antibodies against five distinct antigenic components of M. leprae. Development of systemic mycobacterial infection after inoculation with M. leprae is thus associated with a distinct humoral immune response. The use of radioimmunosassay for selection of animals for inoculation and for following the development of the infection is discussed.

Animals↗
PubMed1978

Mycobacterium leprae specific antibodies detected by radioimmunoassay.

A radioimmunoassay was developed for demonstration of antibodies against M. leprae specific antigenic determinants. The specificity of the assay was tested with hyperimmune rabbit antisera against other mycobacteria and shown to be very high. The titre of M. leprae specific antibodies in a lepromatous serum pool was 10(5). Sixty-one of sixty-two lepromatous sera, all of twelve borderline sera and twenty of forty-eight tuberculoid sera were positive in the assay, whereas all of thirty-eight control sera from tuberculin positive individuals from a leprosy non-endemic area were negative. Aplication as a diagnostic test for subclinical infection with M. leprae is discussed. The principle of the test appears promising for serological distinction between pulmonary infection with M. tuberculosis and other mycobacteria.

Antibodies, Bacterial↗
PubMed1978

Characterization of lymphocytes isolated from non-lymphoid human malignant tumours.

Mononuclear cells (MC) were found in suspensions prepared from twenty-one out of twenty-two solid human neoplasms. In three cases it was calculated that more than 1% of the MC could represent contamination by blood MC. Due to technical difficulties and blood lymphocyte contamination, eight cases were excluded from the study. MC could be separated from thirteen of the remaining fourteen tumours and in one tumour no MC were found. On average, 0.44 X 10(6) MC were obtained from each biopsy weighing 1-5 g. The MC were characterized with regard to markers for T and B lymphocytes. On average 41.0% of the MC were T and 18.2% B cells. There was no significant correlation between MC infiltration and tumour size or spread. In all patients blood MC were also isolated and characterized with regard to T (62.0%) and B lymphocytes (14.3%). The T/B ratio of tumour and blood lymphocytes corresponded in most cases. In two cases a markedly depressed T fraction was found within the tumour, whereas the T lymphocyte portions in the blood of these patients were within the normal range.

Aged↗
PubMed1978

False spurs in quantitative immunoelectrophoresis.

Antigens which show reactions of identity in double-diffusion tests in gel may cause spur formation in crossed immunoelectrophoretic techniques. To differentiate these misleading spurs from spurs of double-diffusion tests which show the true immunochemical relationship between antigens, we have denoted the former type "false spurs". False spurs are often formed in tandemcrossed immunoelectrophoresis and fused rocket immunoelectrophoresis when antigens with different electrophoretic mobility are compared. On the basis of model experiments, criteria are set up for accepting a spur as a true spur, and procedures are described for avoiding formation of false spurs in quantitative immunoelectrophoresis.

Animals↗