title: Lipoteichoic acid and muramyl dipeptide synergistically induce maturation of human dendritic cells and concurrent expression of proinflammatory cytokines.
abstract: Maturation is an important process by which dendritic cells (DC) develop the potent antigen-presentation capacity necessary for efficient activation of adaptive immunity. Here, we have investigated the ability of lipoteichoic acid (LTA) and muramyl dipeptide (MDP; the minimal structural unit of peptidoglycan with immunostimulating activity) to induce maturation of human immature DC (iDC), derived from peripheral blood CD14-positive cells, and the production of proinflammatory cytokines. Exposure of iDC to staphylococcal LTA (StLTA) at 1 or 10 microg/ml or MDP at 0.1 or 1 microg/ml alone had little effect on the expression of CD80 and CD83, with a minor increase in expression of CD86, all of which are indicative of cell surface markers for maturation. However, there was a synergistic expression of these molecules when iDC were stimulated with StLTA and MDP together. It is interesting that selective induction of MHC Class II expression was observed during the DC maturation, only when costimulated with LTA plus MDP, and Escherichia coli LPS induced dramatic expression of MHC Classes I and II. Endocytosis assay using Dextran-FITC showed that costimulation with StLTA and MDP attenuated the endocytic capacity of the DC, which is a typical phenomenon of DC maturation. Concomitantly, increased expression of DEC-205, but decreased expression of CD206, was observed under the same costimulating condition. Furthermore, ELISA showed that secretions of TNF-alpha and IL-12 p40, but not IL-10, were induced in iDC by the costimulation. These results suggest that StLTA and MDP synergistically induce maturation and activation of human DC.
authors.affiliation: Department of Oral Microbiology and Immunology and Dental Research Institute, School of Dentistry, Seoul National University, Seoul 110-749, Republic of Korea.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Kim
authors.forename: Jae Seung
authors.initials: JS
authors.lastname: Yang
authors.forename: Sang Su
authors.initials: SS
authors.lastname: Woo
authors.forename: Sun Kyung
authors.initials: SK
authors.lastname: Kim
authors.forename: Cheol-Heui
authors.initials: CH
authors.lastname: Yun
authors.forename: Kack Kyun
authors.initials: KK
authors.lastname: Kim
authors.forename: Seung Hyun
authors.initials: SH
authors.lastname: Han
mesh_terms: D000119:Acetylmuramyl-Alanyl-Isoglutamine / Q000494:pharmacology*; D002454:Cell Differentiation; D016207:Cytokines / Q000378:metabolism*; D003713:Dendritic Cells / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D004357:Drug Synergism; D004705:Endocytosis; D000949:Histocompatibility Antigens Class II / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000378:metabolism*; D016753:Interleukin-10 / Q000276:immunology / Q000378:metabolism; D018664:Interleukin-12 / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology*; D009000:Monocytes / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D013682:Teichoic Acids / Q000494:pharmacology*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D016207:Cytokines; D000949:Histocompatibility Antigens Class II; D008070:Lipopolysaccharides; D013682:Teichoic Acids; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D018664:Interleukin-12; D000119:Acetylmuramyl-Alanyl-Isoglutamine; C009900:lipoteichoic acid