Serum antibodies to pathogenic actinomycetes in the normal human population.

Sera of persons without known actinomycotic infection (n = 153) were tested for antibodies reacting with antigenic preparations of different Actinomyces spp. and Nocardia spp. By using an enzyme immunoassay, 16% of all of the sera analyzed reacted significantly with antigens of A. viscosus and 2% those of with A. naeslundii. The antigens detected by these antibodies were of low molecular mass (14-32 kDa) and showed a uniform reaction pattern in the immunoblot analysis. Multiple bands coccurred with a difference of approximately 2 kDa in size suggesting the presence of repetitive units. Analogous antibodies were not observed with A. israelii serovar 1 and serovar 2 antigens, which were only insignificantly bound by the sera. The antibodies demonstrated were most probably acquired during episodes of periodontal disease or gingivitis in which A. viscosus is etiologically involved. Antibodies against nocardial antigens were not demonstrated in significant proportions by enzyme immunoassay and immunoblot analysis.

Biosynthesis of the lantibiotic Pep5. Isolation and characterization of a prepeptide containing dehydroamino acids.

Pep5 is a tricyclic peptide antibiotic which contains the unusual amino acids dehydrobutyrine, lanthionine and 3-methyllanthionine. It is matured from a 60-amino-acid precursor peptide (pre-Pep5) deduced from the sequence of the structural gene pepA. To study the biosynthesis of Pep5 we tried to isolate the primary translation product. We identified a peptide in crude extracts of the Pep5-producing Staphylococcus epidermidis strain using antibodies raised against a synthetic 26-residue peptide representing the leader peptide region of pre-Pep5. The putative precursor was purified by reversed-phase HPLC. The isolated peptide did not react with antibodies directed against a C-terminal fragment of mature Pep5 containing two sulfide bridges. Neither lanthionine nor 3-methyllanthionine was detected in amino acid analysis of the isolated precursor. Its amino acid sequence was identical with the sequence predicted from pepA, but Edman degradation stopped at the first threonine residue of the prolantibiotic region indicating a posttranslational modification at this position. The molecular mass of the isolated peptide was 6575.4 +/- 1.7 Da, determined by ion-spray mass spectrometry. This is in agreement with a molecule being dehydrated at the four threonine and the two serine residues in the propeptide region; such a peptide has a calculated molecular mass of 6576.7 Da. The results strongly suggest that maturation of the lantibiotic Pep5 is initiated by selective dehydration of hydroxyamino acids in the propeptide region of the primary translation product and that thioether ring formation is not closely linked to dehydration.

[Serum and cerebrospinal fluid kinetics of ceftazidime]. / Serum- und Liquorkinetik von Ceftazidim.

Ceftazidime serum concentrations and cerebrospinal fluid (CSF) penetration across non-inflamed meninges were evaluated in 10 patients after intravenous application of 2 g ceftazidime over a period of 30 min. After a continuous increase during infusion the highest level of ceftazidime in serum with 172.27 micrograms/ml (+/- 60.43 micrograms/ml) was ascertained at the end of the infusion. The further development demonstrated a continuous decrease of serum concentrations. Concentrations in serum followed a two-compartment open kinetic model. Mean distribution volume was 17.6 l, the total clearance was 142.97 ml/min, half-life was 1.8 h and the determined area under the curve was 139.89 micrograms x min/ml. Penetration of ceftazidime into CSF could only be pointed out in 5 patients. The highest level with 5.11 micrograms/ml (+/- 1.2 micrograms/ml) was observed 32 min after starting the infusion. A steady state with CSF-concentrations over 2 micrograms/ml could be ascertained during the following 4 hours in these patients. Obviously high statistic significance (p less than or equal to 0.01) was present when penetration into CSF was correlated to body surface area (BSA) using the exact Fisher test with Yates correction. Penetration of ceftazidime into CSF across non-inflamed meninges with therapeutic concentrations over a period of 4 hours could only be achieved when BSA was less than 1.95 m2. Further investigations in more patients are necessary to evaluate if BSA is the only parameter which affects distribution of ceftazidime into CSF.

[Laboratory diagnostic possibilities in fungus infections in intensive care patients]. / Labordiagnostische Möglichkeiten bei Sprosspilzinfektionen des Intensivpatienten.

Severe yeast infections of intensive care patients are promoted by numerous predisposing factors among which antibacterial broad spectrum therapy plays an important role. Since typical clinical pictures are lacking, basic procedures of mycological diagnostics are culture and differentiation of yeast strains and detection of immunological reactions against yeast antigens as well. Among 200 intensive-care patients with suspected systemic mycosis, Candida albicans was the prevailing yeast, followed by Torulopsis glabrata and Candida krusei. In the immunocompetent patient, serological procedures discriminating between antibodies of the IgG and IgM class may be suitable for the surveillance of the course of the disease. - In early stages of endomycotic infections and in the immunocompromised host as well, detection of candida antigens by means of specific latex tests and the detection of yeast-specific metabolites (e.g. arabinitol) by gas chromatographic methods provide helpful tools in the diagnosis of severe opportunistic fungal infections.

In situ-differentiation of lymphocytes in fixed tissues with peroxidase-labeled Helix pomatia lectin: revelation of the Helix pomatia lectin receptor on cell surfaces. Application in lymph node tissues and cutaneous lymphomas.

A receptor for Helix pomatia lectin (HPL) occurs on 71.5% of peripheral blood lymphocytes. With double incubation techniques we could show that the population of HPL-positive lymphocytes is by far (greater than 90%) identical with the population of T lymphocytes, as determined by "classical" markers (E rosetting) and newly developed T cell markers like OKT3 or anti-human Lyt3 monoclonal antibodies. In formaldehyde-fixed lymph node sections we could demonstrate the homing area of HPL-positive lymphocytes, the paracortical regions. Conventional histological counterstaining was readily possible. We have employed HPL-peroxidase for differentiation of lymphocytes in benign and malignant infiltrates in human skin. In reactive cutaneous infiltrates, as well as in cutaneous lymphomas, HPL-peroxidase staining allows a clear differentiation of the involved lymphatic cells, and may serve as a tumor marker in certain T lymphomas, where we could demonstrate the lymphoma cells to carry the HPL-receptor.

A new immunoenzyme tracer for localization of antibodies in immunohistology: peroxidase-labeled protein A.

Protein A from Staphylococcus aureus, characterized by high affinity binding properties for IgG-type antibodies, was labeled with peroxidase to form a stable immuno-histological tracer molecule of comparatively low molecular weight. It has been used for demonstration of antibodies against tissue antigens, in direct and indirect techniques, and the findings were consistent with those in routine immunofluorescence and in staining with peroxidase-coupled anti-IgG. In comparison, the lowest unspecific tissue adsorption and staining was obtained with Protein A-peroxidase in buffer containing glucose and mannose. The immunohistological preparations were mounted and stored for documentation without apparent loss of staining.

A new immunoenzyme tracer for immunohistology: peroxidase-labeled protein A. Its application for determination of antinuclear antibodies.

Protein A from Staphylococcus aureus, a cell wall protein with high affinity binding properties for IgG-type antibodies, has been labeled with peroxidase to form a stable immunohistological tracer molecule of relatively low molecular weight. It has been used for demonstration and titration of antinuclear antibodies in SLE sera on mouse liver sections in an indirect technique. The findings were consistent with those obtained by immunofluorescence and by staining with peroxidase-coupled anti-IgG. In contrast to immunofluorescence, the stained sections could be mounted and stored for documentation. In comparison, unspecific tissue adsorption and staining could be minimized by addition of glucose, galactose, and mannose as well as bovine serum albumine to the buffer containing Protein A-peroxidase.

A tumor-cell-agglutinating lectin in snail mucus from Arion lusitanicus (MAB) and Arion empiricorum (Fér.).

A lectin which agglutinates Zajdela hepatoma cells; rat red cells and lymphocytes, but no normal rat liver cells, was detected in the mucus, yielded by simple saline extraction, of the two snail species Arion empiricorum (Fér.) and Arion lusitanicus (MAB). The agglutination spectrum involves also human erythrocytes and red cells of several animal species.