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Biomedical subjects

O Closs

Publications and source records attributed to O Closs.

At least 73 records · Page 4Linked to original sources
PubMed1977

Antibodies against BCG antigen 60 in mycobacterial infection.

A sensitive specific radioimmunoassay was developed to measure antibodies against BCG antigen 60, a prominent antigenic component of BCG bacilli which cross-reacts with similar components in many mycobacterial species including Mycobacterium leprae and M tuberculosis. A lepromatous serum pool had anti-BCG-60 activity with a titre of 10(5) and the tuberculoid pool a titre of 10(4). Testing of individual sera showed striking variations within groups of patients with lepromatous and tuberculoid leprosy. In five of the 20 tuberculoid leprosy sera the anti-BCG-60 activity was above the median for the lepromatous group. The current view that antibody formation against mycobacterial antigens is very low in tuberculoid leprosy thus no longer appears to be tenable. Sera from eight patients with active pulmonary tuberculosis also showed a striking variation in anti-BCG-60 content, and the median value of this group was even higher than in those with lepromatous leprosy.

Antibody Formation↗
PubMed1977

Common antigen of Mycobacterium leprae, M. lepraemurium, M. avium, and M. fortuitum in comparative studies using two different types of antisera.

No. 21 mycobacterial antigens of Mycobacterium lepraemurium, M. avium, M. fortuitum, and M. leprae were compared in crossed immunoelectrophoresis using two different antibody sources, a serum pool from lepromatous leprosy patients (LSII) and a rabbit anti-M. smegmatis antiserum. M. lepraemurium, like M. avium, was found to contain the 21 A and 21 C determinants. M. fortuitum contained in addition a new type of determinant, 21 D.M. leprae antigen no. 21 carried the A as well as the B dertminants, the latter found so far only in the leprosy bacillus. The separate taxonomic position of M. leprae, suggested by earlier studies of the no. 21 antigen, is further supported by the present results, which also demonstrate the potential use of submolecular heterogeneity for such investigations.

Animals↗
PubMed1977

Production and assay of antibodies against one antigenic component of Mycobacterium bovis BCG.

Monospecific antisera against BCG antigen 60 were produced by all of four rabbits during immunization with precipitates containing antigen 60 cut out of gels after crossed immunoelectrophoresis. During electrolytic iodination of a crude antigen 60 preparation, preferential labeling of antigen 60 was demonstrated, and a specific radioimmunoassay was established to follow the development of anti-BCG-60 activity during immunization.

Animals↗
PubMed1977

Antibody response in rabbits to immunization with Mycobacterium leprae.

Mycobacterium leprae purified from liver tissue of an infected armadillo (the A/10 preparation) was tested for antigenic composition by immunization of rabbits and characterization of the antibody response by crossed immunoelectrophoresis. The rabbit antisera detected seven distinct components in the M. leprae preparation. This number is far lower than in similar experiments with other mycobacteria. The M. leprae sonic extract gave far fewer lines after polyacrylamide gel electrophoresis and staining with Coomassie brillant blue than sonic extracts prepared from BCG, M. smegmatis, and M. phlei adjusted to the same protein concentration based on the Folin assay. The seven components detected in M. leprae cross-reacted extensively with M. avium, BCG, M. lepraemurium, M. smegmatis, and Nocardia asteroides. The seven components are involved in immune reactions in leprosy; antibodies against all of them were demonstrated in sera from patients with lepromatous leprosy, but the specificity of the antibodies varied from patient to patient. The reason for the demonstration of so few antigenic components and some of the implications of these findings for the use of armadillo-grown M. leprae to develop specific skin test reagents and in other aspects of leprosy research are discussed.

Animals↗
PubMed1976

Production of monospecific antisera against antigenic componentsof Mycobacterium bovis (BCG).

Monospecific antisera against four different antigenic components of Mycobacterium bovis (BCG) were produced by immunization of rabbits with precipitates cut out of gels after crossed immunoelectrophoresis (CIE). An important feature is to use a semipurified mycobacterial antigenic preparation, or a cross-reactive antigen, to obtain a simpler pattern in CIE so that a clean precipitate, free from contaminating antigens, can be obtained for immunization. The findings with one particular antigen are shown, and the use of such antisera is discussed.

Animals↗
PubMed1975

Experimental murine leprosy. IX. Antibodies against Mycobacterium lepraemurium in C3H and C57BL mice with murine leprosy and in patients with lepromatous leprosy.

Sera from C3H and C57BL mice infected with Mycobacterium lepraemurium (MLM) and from human leprosy patients were examined for antibodies against MLM by a crossed immunoelectrophoresis (CIE) technique. Altogether antibodies against six or seven MLM antigens were found in the mouse sera. After a small inoculum of MLM, C3H mice produced more antibodies than C57BL mice. After a large inoculum both strains produced about the same amount of antibodies but showed qualitative differences in their response patterns. A serum pool from patients with lepromatous leprosy contained antibodies against six MLM antigens; five of these were identical with the antigens against which antibodies were found in infected mice. C57BL mice that had lost their delayed-type hypersensitivity to MLM during the course of a disseminated infection showed a fairly strong antibody response to three antigens and a weak response to three others. Since almost the same spectrum of antibodies, although in lower titres, could be demonstrated in C57BL mice with intact delayed-type hypersensitivity to the bacilli, these antibodies did not seem to interfere with the expression of cell-mediated immunity.

Animals↗
PubMed1975

Experimental murine leprosy. 6. Cellular reactions in the draining lymph node after injection of Mycobacterium lepraemurium into the foot-pads of mice.

The reaction patterns of the draining lymph nodes were studied in C3H and C57/BL mice after foot-pad inoculation of Mycobacterium lepraemurium (MLM). Bacilli were found in the lymph nodes of both strains already a few days after inoculation, but any marked reaction did not occur until approximately 3 weeks later and then only in the lymph nodes of C57/BL mice. The reaction involved enlargement, epithelioid cell granuloma formation and proliferation of pyroninophilic blast cells in the T-cell area. The lymph nodes in these animals remained large and showed a reactive pattern for up to 230 days. At this stage, bacilli were relatively few. In C3H mice, no reactive changes developed and it was not until much later that they became significantly enlarged. In the advanced stage, normal lymph node structures were replaced completely by giant macrophages loaded with acid-fast bacilli. C3H and C57/BL mice are polar as regards the lymph node reaction against MLM; in C3H mice it resembles the advances stages of human leprosy while it in C57/BL mice mimics the situation in the BT-TT region. Immunofluorescence studies did not reveal any early proliferation of Ig-containing cells and the lack of cellular immune reaction against MLM in C3H mice cannot be explained as an early B-cell reaction to interfere with the development of cell mediated immunity.

Animals↗
PubMed1975

In vitro lymphocyte response to purified protein derivative, BCG and Mycobacterium leprae in a population not exposed to leprosy.

Lymphocytes from 14 BCG-vaccinated donors, seven tuberculin positive and seven tuberculin negative by skin testing, were stimulated in vitro with four mycobacterial antigens, purified protein derivative (PPD), PPD/BCG, whole BCG bacilli, and whole Mycobacterium leprae and also with Candida antigen and phytohemagglutinin. The response was measured by incorporation of (3)H-labeled thymidine. The response to PPD, PPD/BCG, and BCG was found to correlate with the result of skin testing with turberculin. The turberculin-positive group also responded more strongly to M. leprae, whereas the two groups did not differ significantly in their response to Candida antigen or phytohemagglutinin. These findings indicate a certain degree of cross-reactivity between BCG and M. leprae. The use of the lymphocyte transformation test to measure antigenic cross-reactivity is discussed.

Adult↗
PubMed1975

Experimental murine leprosy: growth of Mycobacterium lepraemurium in C3H and C57/BL mice after footpad inoculation.

Forty-three female C57/BL and C3H mice were inoculated with 2.7 X 10(6) Mycobacterium lepraemurium into each hind footpad. The foot thickness and the number of acid-fast bacilli in the footpad and popliteal and inquinal lymph nodes were recorded. In addition the morphological index and the mean bacillary length were determined in the footpad and in the popliteal lymph node. The bacilli multiplied in both strains during the first 4 weeks after inoculation. After that time no further increase in acid-fast bacilli was observed in the C57/BL strain; the bacilli became elongated and the morphological index decreased. These changes were preceded by a local swelling of the footpad due to the onset of an immune reaction. Thus, under the present conditions, C57/BL mice were able to resist experimental infection with M. lepraemurium by developing an immune response. In C3H mice no indication of an immune reaction was detected, and the bacilli continued to multiply throughout the observation period. The mouse footpad model seems to provide an excellent basis for the use of experimental murine leprosy to study immunity to mycobacterial infections. Certain aspects of the present model are discussed in relation to the mouse footpad model as used in the study of M. leprae infection in mice.

Animals↗
PubMed1975

Experimental murine leprosy: induction of immunity and immune paralysis to Mycobacterium lepraemurium in C57BL mice.

Two series of reinfection experiments were carried out using C57BL mice. In the first series, the mice were inoculated with Mycobacterium lepraemurium (MLM) in one hind footpad and reinoculated in the contralateral footpad, two or four weeks later. Compared with normal mice of the same strain, the mice reinoculated after four weeks showed an increased local reaction to the bacilli and the bacilli did not multiply at the injection site. The responses of mice reinoculated after two weeks were intermediate to those of the other two groups. In the second series, a systemic infection was established by intraperitoneal innoculation of either a large or small dose of MLM. Twenty-two weeks later the mice were reinoculated in one of the hind footpads. Upon reinoculation, mice receiving the small intraperitoneal dose reacted more strongly than normal mice to MLM, whereas mice receiving the large dose were unable to mount any local reaction to the mycobacterium. The experiments have shown that the local reaction which develops in the C57BL strain of mice approximately four weeks after subcutaneous injection of MLM is accompanied by the onset of systemic immunity. Such systemic immunity lasted for more than 20 weeks after intraperitoneal injection of a small dose of bacilli, but was completely abolished during the course of a heavy systemic MLM infection.

Animals↗
PubMed1975

Experimental murine leprosy. 3. Early local reaction to mycobacterium lepraemurium in C3H and C57/BL mice.

M. lepraemurium was injected subcutaneously into two inbred strains of mice, C3H and C57/BL, in order to study the local reaction at various time intervals. Within 6 hours an acute inflammatory reaction developed at the site of injection. In the course of the following days it was replaced by a mononuclear infiltrate. The influx of mononuclear cells appeared to be somewhat greater in C57/BL than in C3H mice. Apart from this, little difference was observed between the two strains until at 4 weeks when a vigorous granulomatous reaction developed in the C57/BL strain. This reaction apparently arrested further local spread of the infection. The histological appearance of the inflitrate indicated that a delayed hypersensitivity reaction was taking place. No signs of such reaction was observed in the C3H strain.

Acute Disease↗
PubMed1975

Experimental murine leprosy. 4. The gross appearance and microscopic features of the local infiltrate after subcutaneous inoculation of C3H and C57/BL mice with mycobacterium lepraemurium.

Mice with the inbred strains C57/BL and C3H were inoculated subcutaneously on the thorax with M. lepraemurium. In C57/BL mice a firm, raised, sharply defined nodular infiltrate developed 4 weeks afterwards, while in the C3H strain of the infection produced a soft, flattened infiltrate with ill-defined margins, which did not become palpable until 10 weeks after inoculation. A limited spread of the infection occurred early in both strains, but apparently multiplication of the microorganisms was very restricted in C57/BL mice; progressive, disseminated growth of the bacilli was observed in the C3H strain only. In C57/BL mice the granulomatous reaction, developing 4 weeks after inoculation and leading to abcess formation, ulceration and scar formation, apparently inhibited both local multiplication and further spread of the bacilli. In C3H mice no host reaction was detected and the bacilli appeared to grow unrestrictedly. In some C57/BL animals, decrease in host resistance occurred during the infection, causing reactivation of the local lesion and an apparently rapid proliferation of bacilli. Observations regarding the lesions in superinfected animals indicated that a systemic immune reaction develops in the C57/BL strain about 4 weeks after inoculation, whereas this does not occur in the C3H strain.

Animals↗
PubMed1975

Experimental murine leprosy. 8. Ultrastructural features of the inflammatory exudate and bacterial morphology in C3H and C57BL mice after foot-pad inoculation with Mycobacterium lepraemurium.

Mice of the inbred strains C57BL and C3H were inoculated in the foot-pads with Mycobacterium lepraemurium (MLM) and the inflammatory reaction was studied using light and electron microscopy. In C57BL mice a granulomatous reaction developed 3-4 weeks after inoculation. The inflammatory exudate at this stage showed numerous lymphocytes, monocytes and macrophages. The latter cell type often contained many lysosomes and appeared activated. The bacilli which were all within phagosomes showed extensive electron dense aggregates of the cytoplasm suggesting severe damage. Lymphocytes and macrophages in close contact with each other were often observed. In macrophages which contained damaged bacilli, spherical lipid-like bodies surrounded by granular endoplasmic reticulum were observed. It is suggested that this cell product could be of some significance for the bactericidal function of the macrophage. Contrary to these findings, the cellular infiltrate developing in C3H mice showed no lymphocytes and consisted exclusively of macrophages. These were all heavily loaded with bacilli. The vast majority of bacilli encountered in this strain was morphologically intact and presumably viable. Lipid-like bodies similar to those observed in infected C57BL macrophages were not encountered in C3H mice. It is concluded that unless the infected macrophages become immunologically activited they are unable to cause bacterial damage or to inhibit the growth of MLM.

Animals↗
PubMed1975

Stimulation of human lymphocytes by galactose-specific abrus and ricinus lectins.

Human lymphocyte cultures were incubated with the nontoxic abrus agglutinin and with ricin B chain, and the incorporation of 3H thymidine was measured. Abrus agglutinin stimulated strongly the thymidine incorporation whereas ricin B chain had a much lesser effect. When galactose or lactose was added to the cultures together with the lectins, the abrus agglutinin and ricin B chain induced thymidine incorporation was strongly reduced. There was a linear relationship between the concentration of lectin and the concentration of lactose required for inhibition of lymphocyte stimulation. N-acetyl-galactosamine had a much lesser inhibiting effect and alpha-methyl-mannoside did not cause any inhibition. The abrus agglutinin induced thymidine incorporation was not demonstrable before 36 to 40 hr and reached its maximum after 2 to 5 days. If lactose was added within the first 4 hr of incubation with abrus agglutinin no stimulation was observed.

Abrin↗
PubMed1974

BCG antibody profiles in tuberculoid and lepromatous leprosy.

In sera from 12 patients with polar tuberculoid leprosy, 12 with subpolar tuberculoid leprosy, and 16 with lepromatous leprosy were demonstrated a total number of 125 anti-BCG precipitins by means of crossed immunoelectrophoresis with intermediate gel. Up to 14 different precipitins were found in individual sera, and the complexity in antibody response was higher than previously realized. The specificity of 69% of the antibodies was defined, and these antibodies were titrated in three arbitrary titer units. A highly significant difference (P < 0.002) was found in antibody response between the tuberculoid and the lepromatous group. Due to simplicity, sensitivity, and high resolution, the method used is a promising tool for providing exact data to be used as guidelines for purification of important individual mycobacterial antigens. The need for reference antisera is emphasized.

Animals↗
PubMed1974

Evans blue as counterstain in the demonstration of muscle antibodies by immunofluorescence in myasthenia gravis.

The binding of muscle antibodies to skeletal muscle was studied by immunofluorescence techniques. The non-specific fluorescence was not significantly reduced by absorption of the conjugate by tissue powder but was abolished by counterstaining with a 0.1% Evans blue. Possible explanations for this effect are discussed. By this method, immunofluorescence may become more useful in the demonstration of muscle antibodies.

Animals↗