Dendritic Cells/immunology; Dendritic Cells/metabolism; Fluorescein-5-isothiocyanate/analogs & derivatives; Histocompatibility Antigens Class II/physiology; Interleukin-10/biosynthesis; Nuclear Proteins/deficiency; Nuclear Proteins/genetics; Trans-Activators/deficiency; Trans-Activators/genetics; Up-Regulation/genetics; Up-Regulation/immunology; Animals; B-Lymphocyte Subsets/immunology; B-Lymphocyte Subsets/metabolism; Biomarkers/metabolism; Bone Marrow Cells/immunology; Bone Marrow Cells/metabolism; Cell Membrane/genetics; Cell Membrane/immunology; Cell Membrane/metabolism; Cells, Cultured; CpG Islands/immunology; Cytokines/biosynthesis; Dextrans/immunology; Dextrans/metabolism; Down-Regulation/genetics; Down-Regulation/immunology; Fluorescein-5-isothiocyanate/metabolism; Histocompatibility Antigens Class II/genetics; Interleukin-10/antagonists & inhibitors; Interleukin-10/genetics; Lipopolysaccharides/pharmacology; Mice; Mice, Inbred C57BL; Mice, Knockout; Promoter Regions, Genetic/immunology; Retroviridae/genetics; Retroviridae/immunology; Spleen/cytology; Spleen/immunology; Spleen/metabolism; Transduction, Genetic/methods