caa a22 4500 475737792 CHVBK 20180406123451.0 cr unu---uuuuu 170329e20000601xx s 000 0 eng 10.1007/s004300000038 doi (NATIONALLICENCE)springer-10.1007/s004300000038 Infection of dendritic cells by enterobacteriaceae [Elektronische Daten] [Michael Schoppet, Hans-Iko Huppertz, Andreas Simm, Andreas Bubert] Dendritic cells (DC) are potent antigen-presenting cells that play a crucial role in initiation and modulation of specific immune responses. Various pathogens like viruses or bacteria are able to persist inside DC. In this study we investigated the ability of the Gram-negative bacteria Salmonella typhimurium and Escherichia coli to infect DC. DC isolated from peripheral blood of healthy donors were infected with wild-type S. typhimurium and a nonpathogenic E. coli stool isolate. Association of bacteria with DC was assessed by labeling of the bacteria with green fluorescent protein. Both Gram-negative bacteria were associated with DC as evidenced by microscopy and flow cytometry. The intracellular location could be confirmed by lysis of DC and subsequent determination of colony-forming units on agar plates, which showed a rapid decline in viable Gram-negative bacteria 6 h after infection, being by far more pronounced for E. coli than for S. typhimurium. Testing the stimulation of T cells by infected versus uninfected but otherwise identically treated human immature DC in a mitogen-dependent T cell proliferation assay, we found that S. typhimurium, but not E. coli exhibited a suppressive effect on T cell stimulation, being most significant on days 3-5 after infection. Thus, suppression of dendritic cell function was associated with an enteropathogenic bacterium, S. typhimurium, which can cause severe forms of enteritis. The bacteria with normally mild or no gastric symptoms, E. coli, had no influence on stimulation of T cells by DC. Springer-Verlag Berlin Heidelberg, 2000 Key wordsSalmonella nationallicence Escherichia coli nationallicence Dendritic cells nationallicence Immunosuppression nationallicence Bacterial invasion nationallicence Schoppet Michael Children's Hospital, University of Würzburg, 97080, Würzburg, Deutschland aut Huppertz Hans-Iko Children's Hospital, University of Würzburg, 97080, Würzburg, Deutschland aut Simm Andreas Institut für Klinische Biochemie, Universität Würzburg, 97078, Würzburg, Deutschland aut Bubert Andreas Lehrstuhl für Mikrobiologie, Theodor-Boveri-Institut für Biowissenschaften, Universität Würzburg, 97074, Würzburg, Deutschland aut https://doi.org/10.1007/s004300000038 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s004300000038 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Schoppet Michael Children's Hospital, University of Würzburg, 97080, Würzburg, Deutschland aut NATIONALLICENCE 700 1- Huppertz Hans-Iko Children's Hospital, University of Würzburg, 97080, Würzburg, Deutschland aut NATIONALLICENCE 700 1- Simm Andreas Institut für Klinische Biochemie, Universität Würzburg, 97078, Würzburg, Deutschland aut NATIONALLICENCE 700 1- Bubert Andreas Lehrstuhl für Mikrobiologie, Theodor-Boveri-Institut für Biowissenschaften, Universität Würzburg, 97074, Würzburg, Deutschland aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer