Zentralblatt für Bakteriologie, Mikrobiologie und Hygiene. Series A: Medical Microbiology, Infectious Diseases, Virology, Parasitology最新文献

With the present study, the effects of intravenous applications of Staphylococcus epidermidis (SE) on the course of experimental infections of mice with Listeria monocytogenes were evaluated. SE treatment 24 h prior to Listeria infection led to a reduced growth of Listeria organisms in both livers and spleens and to an increased resistance of infected animals against a lethal Listeria challenge. SE treatment 24 h after Listeria infection resulted in an enhanced growth of and retarded elimination of Listeria organisms from animal organs as well as in a reduction of delayed-type hypersensitivity to soluble Listeria antigen. Adoptive immunotherapy accomplished by transferring immune peritoneal exudate T-lymphocyte-enriched cells (PETLEs) to Listeria-infected recipients 24 h before SE treatment did not prevent the delay in clearance of Listeria organisms. When Listeria-infected recipients compromised in their immune response by SE treatment were infused with immune PETLEs either immediately or 24 h after the application of SE, the immunosuppression induced by SE proved to be reversible. It is concluded that, in analogy to other bacterial immunomodulators, Staphylococcus epidermidis is able to either nonspecifically activate macrophages or interfere with T-lymphocyte functions.

Dot blot hybridization was performed for the detection of cytomegalovirus (CMV) genomes in urine samples. This assay was applied to the diagnosis of CMV infection in transplant patients, who were tested continuously after transplantation and the results were compared to the detection of early antigen (EA) in fibroblasts inoculated with urine specimens as well as to serological methods.

It turned out that discrepancies between EA-detection and dot blot hybridization are partially caused by the different appearance and disappearance of the two parameters at different time points. In most cases the dot blot hybridization assay proved to be an earlier marker than EA-detection in the course of infection.

In several patients, however, hybridization showed positive signals although there was no sign for a productive CMV infection.

Dot Blot Hybridisierung wurde zum Nachweis von Zytomegalievirus-(CMV)-Genomen in Harnproben von Transplantationspatienten angewandt. Die Patienten wurden in regelmäßigen Intervallen vom Zeitpunkt der Transplantation an getestet, und die Ergebnisse wurden mit serologischen Daten und dem CMV-Frühantigen-(FA)-Nachweis in den mit Harnproben inokulierten Fibroblasten verglichen.

Unterschiede zwischen FA-Nachweis und Dot Blot Hybridisierung waren offensichtlich größtenteils dadurch bedingt, daß beide Tests in verschiedenen Stadien des Krankheitsverlaufs positive Resultate lieferten. In den meisten Fällen gab die Dot Blot Hybridisierung früher positive Resultate als der FA-Nachweis. Allerdings wurden auch bei einigen Patienten, die sicher nicht produktiv infiziert waren, ebenfalls CMV-Genome gefunden.

Incubation of Propionibacterium acnes but not of Propionibacterium granulosum or Propionibacterium avidum (for 30 min at 37°C in physiological saline) released a soluble factor that produced enhanced chemiluminescence response of human granulocytes as well as increased chemotactic motility of these cells. Sephadex G-25 filtration of the granulocyte activating factor (GAF) revealed its low molecular weight and apparent peptide character. Thus, GAF may be a stimulus for inflammation in acne vulgaris since low molecular weight chemotactic factors can be expected to penetrate follicular walls.

Inkubation von Propionibacterium acnes in physiologischer Pufferlösung (30 Min., 37 °C) bewirkt eine massive Freisetzung eines löslichen, Granulozyten aktivierenden Faktors (GAF); Propionibacterium avidum und Propionibacterium granulosum besaßen diese Fähigkeit hingegen nicht. Im Chemilumineszenz- und Chemotaxis-Test mit menschlichen Granulozyten konnte eine stark gesteigerte Aktivität der Zellen nach Inkubation mit GAF nachgewiesen werden. Sephadex G-25 Filtration des GAF offenbarte ein niedriges Molekulargewicht. Es wird vermutet, daß es sich um ein Peptid handelt. GAF ist offenbar einer der Stimuli für Entzündungsreaktionen in Akne vulgaris. Aufgrund des niedrigen Molekulargewichtes ist anzunehmen, daß GAF die Follikelwand penetrieren und Entzündungserscheinungen initiieren und aufrechterhalten kann.

Under randomized double-blind conditions, 220 medical students were vaccinated with either a 2.5, 5,10, or 20 μg dose of a recombinant yeast-derived hepatitis B or a 20 μg dose of a plasma-derived vaccine. Vaccines were administered at months 0, 1, and 2. After 11 months, all vaccinees received a 20 μg booster dose of the recombinant vaccine.

There were no significant differences in adverse reactions between the study groups. Induction of IgE antibodies to yeast was not observed. One month after the third vaccination, seroconversion rates reached 100% in all vaccinees. Mean anti-HBs levels varied between 150 and 1470 IU/l after 3 vaccinations, with the lowest dose resulting in the lowest titres. Following the booster vaccination, dose-dependent effects were no longer observed. Anti-HBs concentrations were reanalyzed 29 and 36 months after the study had started. The data indicate that the recombinant hepatitis B vaccine is safe and immunogenic for use in man and comparable to the plasma-derived vaccine in terms of safety and efficacy.

In einer randomisierten Doppelblindstudie wurden 220 junge, gesunde Erwachsene mit unterschiedlichen Dosen (2,5; 5; 10; 20 μg) einer neuen, rekombinanten Hepatitis-B-Vakzine auf Hefezellbasis geimpft. In einer Kontrollgruppe erfolgte die Impfung mit der 20 μg Dosis eines Plasmaderivatimpfstoffs. Die Impfungen erfolgten zu Beginn der Studie, nach einem und nach zwei Monaten (0–1–2). Elf Monate nach der ersten Impfung erhielten alle Impflinge die 20 μg Dosis der rekombinanten Vakzine.

Die Nebenwirkungen waren in den 5 Gruppen ähnlich gering. IgE Antikörper gegen Hefematerial wurden nicht induziert. Ein Monat nach der dritten Impfung wurde zu 100% Serokonversion erzielt. Die mittleren anti-HBs-Antikörperspiegel lagen nach drei Impfungen zwischen 150 und 1470 IU/l, wobei die niedrigste Dosis die niedrigsten Werte ergab. Nach der Booster-Impfung wurden keine dosisabhängigen Wirkungen mehr gesehen. In den 5 Impfgruppen lagen zum Monat 12 die mittleren anti-HBs-Werte zwischen 9230 und 51404 IU/l. Kontrolluntersuchungen erfolgten 29 und 36 Monate nach Studienbeginn. Die Studie hat gezeigt, daß die rekombinante Hepatitis B-Vakzine sicher und immunogen beim Menschen ist und vergleichbare Wirkungen wie der Plasmaderivatimpfstoff zeigt.

Binding of ¹²⁵I-fibronectin, its ¹²⁵I-labelled 29-kDa aminoterminal fragment, and ¹²⁵I-collagen to cells of 13 Salmonella strains grown in broth and agar media at three different temperatures was studied. Of the 13 strains, 7 had only smooth colony morphologies while three strains were pairs of both smooth strains and their corresponding rough variants. The three rough variants showed higher binding to fibronectin, it's 29-kDa fragment and to collagen, than the corresponding smooth forms. However, the percentage of ¹²⁵I-protein bound was greatly influenced by the growth conditions. In these three pairs of strains, there was a direct correlation between cell-surface hydrophobicity and the binding activity, but this correlation was not observed in the remaining strains. Thus, some of the strains showed high cell-surface hydrophobicity but low binding activity under optimal growth conditions. The highest binding rates of fibronectin and of it's 29-kDA fragment were obtained with bacteria grown on colonisation factor antigen (CFA) agar at 33 °C, while the binding to collagen was slighly higher when bacteria were cultured on tryptic soy agar.