Salmonella enterica Serovar Typhimurium-Induced Maturation of Bone Marrow-Derived Dendritic Cells MATTIAS SVENSSON, CECILIA JOHANSSON,
AND
MARY JO WICK*
Department of Cell and Molecular Biology, Section for Immunology, Lund University, Lund, Sweden Received 30 May 2000/Returned for modification 26 June 2000/Accepted 16 August 2000
Murine bone marrow-derived dendritic cells (DC) can phagocytose and process Salmonella enterica serovar Typhimurium for peptide presentation on major histocompatibility complex class I (MHC-I) and MHC-II molecules. To investigate if a serovar Typhimurium encounter with DC induces maturation and downregulates their ability to present antigens from subsequently encountered bacteria, DC were pulsed with serovar Typhimurium 24 h prior to coincubating with Escherichia coli expressing the model antigen Crl-OVA. Quantitating presentation of OVA epitopes contained within Crl-OVA showed that Salmonella-pulsed DC had a reduced capacity to process Crl-OVA-expressing E. coli for OVA(257-264)/Kb and OVA(265-277)/I-Ab presentation. In addition, time course studies of DC pulsed with Crl-OVA-expressing serovar Typhimurium showed that OVA(257-264)/Kb complexes could stimulate CD8OVA T-hybridoma cells for 24 but
