Background: species, particularly , but also constitute emerging pathogens causing gastroenteritis in humans. However, isolation of may often fail during routine diagnostic procedures due to the lack of standard protocols. Furthermore, defined breakpoints for the interpretation of antimicrobial susceptibilities of are missing.
View Article and Find Full Text PDFBackground: constitute emerging food- and waterborne pathogens causing gastroenteritis in humans, but the underlying mechanisms are only incompletely understood. We therefore characterized isolates derived from human stool samples that had been collected during a prospective prevalence study in Germany in vitro. Thirty-six bacterial isolates belonging to the species (n = 24), (n = 10) and (n = 2) were genotyped by ERIC-PCR, the presence of 10 putative virulence genes was assessed and cytotoxic effects on the human intestinal cell line HT-29/B6 were analyzed applying the WST-assay.
View Article and Find Full Text PDFInt J Hyg Environ Health
March 2019
In Germany community-acquired Legionnaires' disease is usually caused by the species Legionella pneumophila. Recurrent cases of Legionnaires' disease are rarely reported and are due either to a second infection (reinfection) or a relapse of a previous case. We report a case of recurrent Legionnaires' disease in an 86-year-old female patient infected with Legionella pneumophila serogroup 1, monoclonal antibody-subtype Knoxville, sequence type unknown.
View Article and Find Full Text PDFBackground: Bacterial vectors have been proposed as novel vaccine strategies to induce strong cellular immunity. Attenuated strains of Brucella abortus comprise promising vector candidates since they have the potential to induce strong CD4(+) and CD8(+) T-cell mediated immune responses in the absence of excessive inflammation as observed with other Gram-negative bacteria. However, some Brucella strains interfere with the maturation of dendritic cells (DCs), which is essential for antigen-specific T-cell priming.
View Article and Find Full Text PDFStudying the interaction of dendritic cells (DCs) with bacteria controlled by T-cell-mediated immune responses may reveal novel adjuvants for the induction of cellular immunity. Murine studies and the observation that nocardias infect predominantly immunosuppressed patients have suggested that these bacteria may possess an adjuvant potential. Moreover, adjuvants on the basis of the nocardial cell wall have been applied in clinical studies.
View Article and Find Full Text PDFPerfluoroalkyl carboxylic acids (PFCA) are commercially used for their surfactant properties combined with chemical and thermal stability. Differentiation of peripheral monocytes to immature dendritic cells (DCs) in the presence of the PFCA, ammonium perfluorooctanoate (APFO, 200 microM) led to a considerably increased expression of CD86 and HLA-DR on immature DCs. However, these phenotypic changes were not reflected by an increased T cell-stimulatory capacity of the cells.
View Article and Find Full Text PDFToll-like receptor (TLR) ligands are being considered as adjuvants for the induction of antigen-specific immune responses, as in the design of vaccines. Polyriboinosinic-polyribocytoidylic acid (poly I:C), a synthetic double-stranded RNA (dsRNA), is recognized by TLR3 and other intracellular receptors. Poly ICLC is a poly I:C analogue, which has been stabilized against the serum nucleases that are present in the plasma of primates.
View Article and Find Full Text PDFExperimental studies in monkeys on the basis of ex vivo-generated, reinjected dendritic cells (DCs) allow investigations of primate DC biology in vivo. To study in vitro and in vivo properties of DCs with a reduced capacity to produce IL-12, we adapted findings obtained in vitro with human cells to the rhesus macaque model. Following exposure of immature monocyte-derived monkey DCs to the immunomodulating synthetic polypeptide glatiramer acetate (GA) and to dibutyryl-cAMP (d-cAMP; i.
View Article and Find Full Text PDFAdoptive cell transfer may be a successful strategy in anticancer therapy and its therapeutic efficiency depends on the access of transferred cells to the tumor site and their persistence in vivo. Nevertheless, the migration properties of autologous in vitro-activated T cells in primates are largely unknown. Here, we established the long-term tracking of T-cell migration into various compartments of rhesus macaques as a preclinical model for the evaluation of T-cell-based immunotherapy.
View Article and Find Full Text PDFElucidating the mechanisms that protect monkeys previously immunized with attenuated SIV (SIVDeltanef) against challenge infection with pathogenic virus may reveal new strategies for the development of an effective HIV vaccine. Here we show that a single atraumatic application of SIVDeltanef to the tonsils of four rhesus macaques conferred protection against SIVmac251 applied intrarectally 26 weeks later. While this protection was not complete, i.
View Article and Find Full Text PDFOligonucleotides containing CpG motifs (CpG ODN) are strong adjuvants for humoral immune responses but data on cellular immune responses in primates are scarce. Rhesus macaque blood contained similar numbers of plasmacytoid dendritic cells and B cells, the key sensors of CpG ODN, as human blood, and these cells were activated by CpG-A and CpG-B in vitro. In vivo, both ODNs induced equal plasma levels of interferon-inducible protein 10 and similarly enhanced antibody responses following i.
View Article and Find Full Text PDFGranulocyte/macrophage-colony stimulating factor (GM-CSF) is a valuable adjuvant to enhance induction of cellular immune responses in rodents. Less information is available regarding its use as an adjuvant in primates or humans. We explored recombinant human GM-CSF for potential vaccine studies in rhesus macaques and focused on its effect on peripheral monocytes as progenitors of dendritic cells and its potential immunogenicity.
View Article and Find Full Text PDFTo elucidate Campylobacter jejuni resistance to antibiotics in Germany, MICs of ciprofloxacin, moxifloxacin, erythromycin, clindamycin, and tetracycline were determined (using agar dilution) for 144 clinical isolates. The data indicate a considerable ciprofloxacin resistance (45.1%) without a clonal relationship of the strains and a greater in vitro activity of moxifloxacin, erythromycin, and clindamycin.
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