Identification and characterization of DC-SCRIPT, a novel dendritic cell-expressed member of the zinc finger family of transcriptional regulators.

Contains fulltext : 51364.pdf (publisher's version ) (Closed access)Dendritic cells (DC) compose a heterogeneous population of cells that hold a leading role in initiating and directing immune responses. Although their function in recognizing, capturing, and presenting Ags is well defined, the molecular mechanisms that control their differentiation and immune functions are still largely unknown. In this study, we report the isolation and characterization of DC-SCRIPT, a novel protein encoded by an 8-kb mRNA that is preferentially expressed in DC. DC-SCRIPT is expressed in multiple DC subsets in vivo, including myeloid DC, plasmacytoid DC, and Langerhans cells. At the protein level, DC-SCRIPT consists of a proline-rich region, 11 C2H2-type zinc fingers, and an acidic region. Localization studies reveal that DC-SCRIPT resides in the nucleus and that nuclear localization is critically dependent on the zinc fingers. The protein displays no transcriptional activation properties according to assorted transactivation assays, but interacts with the corepressor C-terminal binding protein 1. Taken together, our results show that we have isolated a novel DC marker that could be involved in transcriptional repression. In contrast to other DC molecules, DC-SCRIPT identifies all DC subsets tested to date

Quantitative analysis of chemokine expression by dendritic cell subsets in vitro and in vivo

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Genomic organization, chromosomal localization, and 5' upstream region of the human DC-STAMP gene.

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LDTFs look to 2009 and beyond.

Item does not contain fulltextDC-CK1 (CCL18) is a dendritic cell (DC)-specific chemokine expressed in both T and B cell areas of secondary lymphoid organs that preferentially attracts CD45RA(+) T cells. In this study, we further explored the nature of DC-CK1 expressing cells in germinal centers (GCs) of secondary lymphoid organs using a newly developed anti-DC-CK1 mAb. Immunohistochemical analysis demonstrated a remarkable difference in the number of DC-CK1 expressing cells in adjacent GCs within one tonsil, implicating that the expression of DC-CK1 in GCs depends on the activation and/or progression stage of the GC reaction. Using immunohistology and RNA analysis, we demonstrated that GCDC are the source of DC-CK1 production in the GCs. Considering the recently described function of GCDC in (naive) B cell proliferation, isotype switching and Ab production, we investigated the ability of DC-CK1 to attract B lymphocytes. Here we demonstrate that DC-CK1 is a pertussis toxin-dependent chemoattractant for B lymphocytes with a preference in attracting mantle zone (CD38(-)) B cells. The findings that GCDC produce DC-CK1 and attract mantle zone B cells support a key role for GCDC in the development of GCs and memory B cell formation

Reduced cord blood immune effector-cell responsiveness mediated by CD4+ cells induced in utero as a consequence of placental Plasmodium falciparum infection.

Contains fulltext : 50468.pdf (publisher's version ) (Closed access)To determine mechanisms of neonatal parasite antigen (Ag)-specific immune suppression associated with placental Plasmodium falciparum infection, we isolated cord blood mononuclear cells (CBMCs) from Gabonese neonates born to mothers with differing histories of P. falciparum infection and performed ex vivo and in vitro studies to evaluate immune regulatory activity. We found increased ex vivo percentages of CD4(+)CD25(hi) and CD4(+)CD25(+)CTLA-4(+) cells and increased interleukin (IL)-10 responses to parasite Ag in vitro in CBMCs from neonates born to mothers with placental P. falciparum infection at delivery. Depleting CBMCs of CD4(+)CD25(+) cells before cell culture led to the abrogation of parasite Ag-specific IL-10 responses, to enhanced interferon- gamma responses, and to enhanced expression of CD25 on CD8(+) T cells and of major histocompatibility complex class I and II on monocytes. These data demonstrate that parasite Ag-specific CD4(+) regulatory cells are generated in utero as a consequence of placental P. falciparum infection

DC-STAMP, a novel multimembrane-spanning molecule preferentially expressed by dendritic cells

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Food Allergy in Ghanaian Schoolchildren: Data on Sensitization and Reported Food Allergy

Background: Epidemiological data on food allergy are scarce in African countries. We studied the prevalence of food sensitization in Ghanaian schoolchildren. Methods: Children (5-16 years; n = 1,714) from 9 Ghanaian schools were given parental consent to participate in the study. Adverse reactions and food consumption were determined by a questionnaire and atopy by skin prick testing (SPT) to peanut and 6 fruits. Subjects with positive SPTs were considered cases (n = 43) and matched with at least 1 control (n = 84), using age, sex, and school as matching criteria. Serum samples from case-control sets were analyzed for specific IgE (sIgE) to foods that elicited a positive SPT response in cases. Results: Overall, 11% of 1,407 children reported adverse reactions to foods, and 5% of 1,431 children showed a positive SPT reaction mostly directed against peanut and pineapple (both 2%). Although there was a positive association between adverse reactions and SPT responses to any food allergen in the urban children (adjusted OR = 3.6, 95% CI 1.2-10.8), most of the reported adverse reactions were not in children showing an SPT reaction to the specific food item. sIgE sensitization was very variable for the different foods, ranging from 0 to 100% in cases, and from 0 to 25% among controls. High IgE levels for a food item significantly increased the risk of SPT positivity to any food item in the urban, but not in the rural, schoolchildren. Conclusions: Specific foods were identified to be allergenic in Ghana. We show a good association between SPT and sIgE in urban, but not in rural, schoolchildren. However, there was no clear association between reported adverse reactions to food and SPT or sIgE.Host-parasite interactio

Analysis of dendritic cells at the genetic level

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Characterization of DC at the molecular level

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