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Biomedical subjects

C Koch

Publications and source records attributed to C Koch.

At least 451 records · Page 25Linked to original sources
PubMed1982

Specificities of anti-rabbit VH antibodies in mammalian and fowl antisera.

Antibodies against rabbit VH-determinants were produced by immunizing mammals and birds with rabbit IgG, IgA or VH. Most of the anti-VH produced in mammals was specific for allotype VH-determinants, but small amounts of antibody against non-allotype VH-determinants were also produced. By contrast the immunization of chickens led to the production of predominantly non-allotype VH antibody. Further analysis of the antibody specificity revealed the production of antibody against VH-determinants available in the intact immunoglobulin (H- + L-chain) as well as antibody reacting with determinants only accessible in the absence of L-chain. Antibody of the latter specificity prevailed after immunization with VH. The purified VH was not deficient in antigen determinants when compared with VH in the intact immunoglobulin (IgA). Unexpectedly, none of our chicken anti-rabbit VH antisera showed crossreactivity with VH from other mammalian species.

Animals↗
PubMed1982

Diagnostic value of fibrinopeptide A and beta-thromboglobulin in acute deep venous thrombosis and pulmonary embolism.

The purpose of this study was to assess the predictive values of the assays of fibrinopeptide A (FPA), beta-thromboglobulin (BTG) and their combination in patients suspected of having acute deep venous thrombosis (DVT) or pulmonary embolism (PE). In 80 controls the mean (+/- SD) plasma concentrations of FPA and BTG were 0.72 +/- 0.47 and 28.2 +/- 10.1 ng/ml, respectively. In 26 patients in whom DVT was confirmed by phlebography and Doppler ultrasound, clearly raised mean FPA (5.62 ng/ml) and BTG (70.6 ng/ml) concentrations were measured compared to those in 13 patients in whom this disorder was excluded (1.00 and 33.6 ng/ml, respectively). Also in 25 patients, in whom PE was established by perfusion lung scanning, clearly increased mean FPA (6.28 ng/ml) and BTG (82.4 ng/ml) concentrations were measured compared to those in 12 patients without this disease (1.03 and 32.5 ng/ml, respectively). Raised FPA and BTG concentrations were also found in 20 patients with inflammatory disorders and in 10 with various types of malignancy. The mean FPA and BTG concentrations did not differ between patients with renal failure or diabetes mellitus and patients without these diseases. From the predictive values of these assays and their combination it can be concluded that raised FPA and BTG concentrations are not specific for thrombosis. However, when normal FPA and BTG concentrations are present, acute DVT or PE can safely be excluded in symptomatic patients. In the group with confirmed DVT/PE, anticoagulant treatment (heparin and phenprocoumon) brought down the mean FPA concentration to levels within the normal range in less than 1 hour while the mean BTG concentration remained elevated throughout the 10-day study period.

Acute Disease↗
PubMed1982

Studies on hypersensitivity to bacterial antigens in intrinsic asthma.

Twelve children, aged 4 to 14 years, with moderate to severe intrinsic asthma (IA) were studied. Symptom-Score charts were used to confirm the relationship of acute respiratory tract infections to exacerbations of asthma. Hypersensitivity to eight commonly occurring bacteria from the normal flora of the upper respiratory tract was studied by skin test, by crossed immunoelectrophoresis, and by basophil histamine release in vitro, using ultrasonicates of the bacteria as antigens. Skin tests were all negative. All children contained low titers of precipitating antibodies against most of the bacteria, but in this respect they did not differ from normal children. In contrast, release of histamine was induced in leukocytes from the IA children by all, or most sonicates, while such reactions, were less frequent in control children. The pattern of responses indicated an element of specificity. These was no correlation to precipitating antibodies, or to the microbial flora of the children. Positive responses were characterized by low values of maximal histamine release, and by a tendency to fluctuations with time. Because of these fluctuations, and because the IA children and control children were tested on separate occasions, we cannot be certain as to the real difference between these two groups. Our studies do, however, demonstrate that water-soluble constituents of all the bacterial strains tested were capable of causing the release of histamine in vitro, but that this phenomenon is not restricted to IA. The clinical significance of these findings awaits further investigations on the mechanism(s) of release in vitro by such agents.

Acute Disease↗
PubMed1982

Treatment of pulmonary Pseudomonas aeruginosa infection in cystic fibrosis with cefsulodin.

20 patients with cystic fibrosis and chronic pulmonary Pseudomonas aeruginosa infection underwent a total of 23 courses of treatment with a new cephalosporin, cefsulodin. The patients were given 100-150 mg/kg/day in 3 divided doses for 14 days, alone or in combination with tobramycin. Maximum serum levels were around 150 microgram/ml and 6-h levels above 5 micrograms/ml. 90% of the infecting strains were sensitive to 5 micrograms/ml in vitro. Apart from discomfort in direct relation to intravenous bolus injection the drug was well tolerated. Clinical improvement was pronounced, and in 5 cases. P. aeruginosa disappeared from bronchial secretions. Patients allergic to carbenicillin tolerated cefsulodin without signs of allergy. Cefsulodin thus appears to be an effective alternative to carbenicillin in the treatment of severe P. aeruginosa infections.

Adolescent↗
PubMed1981

Evidence for two populations of B-L (Ia-like) molecules encoded by the chicken MHC.

Two specific alloantisera detecting B-L (Ia-like) antigens on chicken lymphocytes of the B6 and B15 haplotypes were found to cross-react strongly. Anti-B-L6 and anti-B-L15 alloantisera both reacted with B-L molecules on B6 and B15 lymphocytes as demonstrated by immunofluorescence and SDS-PAGE analysis of 125I-labeled B-L antigens isolated by incubation with anti-B-L alloantisera. Absorption studies showed that the anti-B-L alloantisera reacted with at least two kinds of antigenic determinant, one set shared by B-L6 and B-L15 molecules and another set specific for each haplotype. In spite of the absence of genetic evidence for more than one B-L locus in the chicken B complex, it was shown by sequential antibody incubations that these two different B-L antigenic determinants are associated with at least two separate species of B-L molecules, indicating the presence of at least two B-L loci within the MHC of the chicken.

Animals↗
PubMed1981

Eggs: conveniently packaged antibodies. Methods for purification of yolk IgG.

Eggs from immunized chickens may provide a convenient and inexpensive source of antibodies. We describe two simple and efficient methods for purification of IgG from yolk. The antibody is rendered useful for most currently employed immunological techniques. Amounts of antibody corresponding to almost half a litre of antiserum may be recovered from a chicken in one month.

Animals↗
PubMed1981

Characterization of conjugative R plasmids belonging to the new incompatibility group IncU.

Five conjugative plasmids governing different antibiotic resistance patterns were identified in wild strains of enteric bacteria isolated in Czechoslovakia and the G.D.R. between 1976 and 1979. They have been characterized as members of the new incompatibility group IncU (reference plasmid RA3 from Japan). The molecular sizes of the IncU plasmids ranged between 18 and 37 megadaltons; their restriction fragment patterns indicated them to be distinct types.

Citrobacter↗
PubMed1981

Discoid lupus erythematosus-like lesions and stomatitis in female carriers of X-linked chronic granulomatous disease.

The skin and oral mucosa were studied in an unselected series of carriers of x-linked chronic granulomatous disease, a hereditary condition in which phagocytic cells display a pronounced functional defect. Three carriers had discoid lupus erythematosus (DLE)-like skin lesions which histopathologically were consistent with DLE of the hypertrophic and profundus type. Four patients had experienced photosensitivity in childhood. Seven patients had recurrent aphthous-like stomatitis which should be distinguished from the recurrent aphthous stomatitis seen in otherwise healthy individuals. The remarkably high incidence of DLE-like symptoms in heterozygous carriers might be related to the presence of mixed populations of defective and normal phagocytes. The variable expression of skin symptoms may be related to uneven distribution of abnormal and normal phagocytes. Female patients with these clinical symptoms, especially the combination of DLE-like skin lesions and aphthous-like stomatitis, should be suspected of being carriers of chronic granulomatous disease and studies of phagocyte function in vitro should be performed, since the diagnosis of the carrier state is of utmost importance for genetic counselling before pregnancy.

Adult↗
PubMed1981

Haemagglutination-enhancing factor protein in chicken serum. I. Purification of an active protein and production of a monospecific antiserum against it.

The haemagglutinating activity of the IgG fraction of chicken alloantibodies is greatly enhanced by the addition of normal chicken serum. The effect is due to a macromolecular beta-globulin, which has been purified by salt precipitation, gel filtration, and ion-exchange chromatography. Immunization of rabbits with the purified product gave a monospecific antiserum against the haemagglutination-enhancing factor (HEF) protein. By means of this rabbit antiserum it is shown that HEF is co-precipitated with antigen-antibody complexes. This indicates that HEF exerts its effect by binding to chicken IgG antibody after the latter has reacted with antigen.

Animals↗
PubMed1981

B-L antigens (Ia-like antigens) of the chicken major histocompatibility complex.

This paper reviews the present knowledge of B-L antigens encoded by the chicken B complex as regards to the following aspects: (1) identification and cellular expression, (2) structural studies, (3) evidence for two distinct populations of B-L antigens, (4) mapping of B-L loci of the B complex, (5) B-L and immune response, and (6) the role of the B-L antigens for the control of mixed lymphocyte reactions (MLR) and graft-versus-host (GVH) reactions. It is concluded that B-L antigens of the chicken exhibit extensive homology with mammalian Ia antigens. A genetic map of the B complex is presented.

Animals↗
PubMed1981

The still elusive T cell receptor: on the possibility of a common V-gene pool for B- and T-cell-antigen receptor molecules.

The contention that VH constitutes a part of T-cell receptors for antigens was probed by purifying rabbit T cells and analysing these cells for non-immunoglobulin VH, i.e. VH not associated with L chain. A number of anti-VH antisera were employed for this purpose, the most important being goat antiserum, reacting with common a1 allotype determinants (allotype determinants expressed on free VH and H chain as well as on intact immunoglobulins), rat antibody against common non-allotype VH determinants (VH framework determinants expressed on VH and H chain as well as on intact immunoglobulins) and chicken antibody against unmasked non-allotype determinants (VH determinants accessible only in the absence of L chain). VH and L chain was quantified by radioimmunoassays on extracts and supernatants from unstimulated T cells as well as from T cells stimulated by concanavalin A and by allogeneic cells. Absolute depletion of Ig-containing and -producing cells was not achieved but in no case was an excess of VH over L chain observed. This indicated that all detected VH originated from cells of the B lineage. The cells were also cultured in the presence of labelled amino acids followed by analysis of detergent extracts and supernatants by immunoadsorption and sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) fluorography. Again, no evidence for T-cell VH could be found. Affinity purified anit-VH antibody was used to label viable rabbit T cells through the use of secondary fluorescence-labelled anti-immunoglobulin antibody. No VH-specific labelling of T cells could be observed. Mixed lymphocyte cultures were carried out in the presence of affinity-purified anti-VH antibodies. No inhibition of the reaction could be discerned. The failure to detect T-cell VH is in agreement with the recent finding that the VH-genome in T cells is not rearranged in a functional manner similar to that in B cells.

Animals↗
PubMed1981

Studies on the thymus-dependent immunity in the rat mutant "nude".

Different T-cell capacities in nude, athymic rats were tested. Spleen cells from nude rats were unable to give significant responses to Con A as could spleen cells from normal rats. No precipitating antibodies after immunization with chicken serum were observed in nude rats, although such antibodies were found in the haired rats. The experiments confirmed that the used stock of nude rats had a similar T-cell defect as the original Rowett strain of nude rats.

Animals↗
PubMed1981

Relation of monocyte and neutrophil oxidative metabolism to skin and oral lesions in carriers of chronic granulomatous disease.

Out of fifteen carriers of X-linked chronic granulomatous disease five had discoid lupus erythematosus-like skin lesions together with recurrent aphthous-like stomatitis, another five had only recurrent aphthous-like stomatitis, and the remainder were symptom-free. In individual carriers monocytes and neutrophils were equally reduced in their capacity for superoxide production, [1-14C]glucose oxidation and antibody-dependent cytotoxicity; but within he group of carriers a broad spectrum of depression was found. The degree of depression was closely related to the manifestations of clinical disease. It is suggested that the defective oxygen-dependent metabolism might play an aetiological role in the development of inflammatory diseases in carriers of chronic granulomatous disease. Two out of 10 unselected females with discoid lupus erythematosus were shown to be carriers of X-linked chronic granulomatous disease. Screening for this carrier state might therefore be of importance in these patients.

Adult↗