Epidemiologic studies have associated exposure to airborne particulate matter (PM) with exacerbations of asthma. pattern of cytokine production (e.g., enhanced IL-13 and IL-18 and suppressed IFN- production). CD4+ T cells were not functionally triggered on exposure to either DEP AB1010 or CEP. Car- and diesel-enriched particles exert a differential effect on DC activation. Our data support the hypothesis that DEP (and to a lesser degree CEP) regulate important functional aspects of human being DC, assisting an adjuvant part for this material. serotype 0.55:B5) and fluorescein isothiocyanate (FITC)-conjugated dextran (MW of 40,000), were from Sigma-Aldrich (St. Louis, MO). Recombinant human being trimeric CD40-Ligand (CD40L trimer) was a kind gift from Dr. John McDyer, Johns Hopkins University or college. The following monoclonal antibodies were used for circulation cytometry on activation of DC: FITC-conjugated antibodies were IgG1- (isotypic control, clone MOPC-21), HLA-DR (IgG2a-, clone G46C6), and CD206 (IgG1, clone 19.2); phycoerythrin (PE)-conjugated antibodies were IgG1- (isotypic control, clone MOPC-21), IgG2a- (isotypic control, clone G155C178), CD4 (IgG1-, clone RPA-T4), CD80 (IgG1, clone L307.4), CD83 (IgG1, clone HB15e), CD86 (IgG1, clone FUN-1), and CD14 (IgG2a, clone M5E2), all from PharMingen (San Diego, CA). The following PE-conjugated antibodies were from Santa Cruz Inc. (Santa Cruz, CA); TLR-2 (IgG2a, clone TL2.3) and TLR4 (IgG2a, clone HTA125). FITC-conjugated CD40 (IgG1, clone HB14) was from Caltag (Burlingame, CA). The following monoclonal AB1010 antibodies were used for circulation cytometry on activation of CD4+ T cells: FITC-conjugated antibodies were IgG2a- (isotypic control, clone G155C178) and HLA-DR (IgG2a-, clone G46C6, L243); PE-conjugated fluorochromes were IgG1- (isotypic control, clone MOPC-21), IgG2a- (isotypic AB1010 control, clone G155C178), CD4 (IgG1-, clone RPA-T4), CD11b (IgG2a-, clone D12), CD31 (anti-PECAM1; IgG1-, clone L133.1), CCR7 (Rat IgG2a-, clone 3D12), and CD62L (L-selectin or LAM1, IgG1-, clone Dreg 56). Preparation and Enrichment of Highly Pure CD4+ Allogeneic T Cells The methods used to enrich for these cells has been explained (14). In assays of allogeneic T cell reactions, CD4+ T cells were enriched from whole blood using the Rosettesep bad selection system according to the manufacturer’s instructions (Stem Cell Systems, Ltd, Vancouver, BC, Canada). This system depletes the contaminating cells by immunologically cross-linking those cells in whole blood to multiple reddish blood cells (immunorosettes) using an antibody cocktail. In this procedure, the density of the rosetted cells raises and they can be pelleted with free red blood cells by centrifugation over low endotoxin (< 0.12 EU/ml, where 1 EU = 100 pg/ml LPS) cell separation medium (Ficoll-Paque In addition, d = 1.077 g/cm3; GE Healthcare Biosciences Abdominal, Uppsala, Sweden). Briefly, after rosetting cells for 20 moments at space temperature, the blood sample was diluted with an equal volume of divalent cation-free PBS supplemented with 2% vol/vol FBS, combined gently, layered over Ficoll-Paque and centrifuged at 800 for 30 minutes at space heat. Enriched cells were harvested from your separation medium/top plasma interface then washed twice in PBS/2% FBS buffer. By this procedure, the cells were 95% 4% viable by trypan blue dye exclusion assay and cell counting and 92% 4% enriched CD4+ T cells by staining with FITC-conjugated anti-human CD4 (clone RPA-T4, IgG1) and circulation cytometry (data not shown). This method of CD4 T cell purification was chosen because of its high reproducibility of enrichments between donors. Generation, Expansion, and Activation of CD34+ Peripheral Blood Progenitor CellCDerived DC DC were generated from CD34+ enriched Capn1 peripheral blood progenitor cells (PBPC) using protocols that use cytokine-driven growth and propagation of DC precursors (21). PBPC were from an NIH core facility in the University or college of Washington (Seattle, WA) and were used as the starting material for the generation AB1010 of myeloid DC. Enriched CD34+ PBPC were seeded into 6-well tradition dishes at 2.5 105 cells/ml in a total volume of 4 ml DC culture medium inside a 5% CO2/95% air fully humidified atmosphere. DC were cultured continuously for 14 days in DC tradition medium that had been previously optimized AB1010 in pilot experiments. For the tradition of PBPC-derived DC, RPMI 1640 foundation culture medium (GIBCO/BRL, Invitrogen, Carlsbad, CA) was used and supplemented with 8% vol/vol FBS, 2 mM L-glutamine, 1 mM sodium pyruvate, 1% vol/vol nonessential amino acids (GIBCO-BRL), 1 g/mL.