: This is a revised, new application to examine the role of dendritic cells (DC) in the induction of Th2 responses to schistosome antigens. Initiation of the immune response to extracellular pathogens such as schistosomes occurs when DC present antigen (Ag) peptides to CD4+ T helper (Th) cells. This signal, along essential co-stimulatory signals from other DC surface molecules, promotes clonal expansion of T cells expressing relevant TCR. Thereafter the immune response focuses such that the majority of Th cells proceed to produce similar panels of effector cytokines. The outcome is usually an immune response dominated by Th1 or Th2 cells, where Th1 cells make IFN-g and IL-2, whereas Th2 cells make IL-4, -5, -6, -10 and -13. Expression of the transcription factors T-bet or GATA3 are respectively essential for acquisition of the Th1 or Th2 phenotype. IL-12 selects strongly for Th1 cells and IL-4 selects for Th2 cells. DC participates in Th1 by making IL-12 directly in response to certain microbial pathogens and upon ligation of CD40 by CD 154. However, little is known of the DC response to pathogens that induce Th2 responses. The hypothesis to be tested is that DC, by recognizing pathogen associated molecular patterns on schistosome Ag, respond in a way that is yet to be fully characterized, but which is distinct from their response to Th1 Ag, to orchestrate the development of a Th2 response. The following specific aims are designed to test this hypothesis:
Specific Aim 1) To delineate the differences in the response of DC to schistosome Ag (which induce Th2 responses) versus their response to Th1 Ag (e.g., Propionebacterium acnes).
Specific Aim 2) To link DC phenotype following exposure to schistosome Ag to the induction of Th2 responses by these Ag, with a focus on the role of soluble mediators and on co-stimulatory signals.
Specific Aim 3) To assess the function of DC in promoting Th1 and Th2 responses in vivo following the injection of Ag and during infection. We will use micro-arrays, proteomics and subtractive cDNA libraries to identify genes expressed specifically by schistosome Ag-stimulated DC, combined with an adoptive transfer system in which DC are pulsed with Ag in vitro and injected into mice to examine the influence of identified genes on Th response outcome. DC activation during infection will be examined and the interaction of DC with other immune system cells will be investigated using flow cytometry and immunofluorescence microscopy. The long-term goal of this approach is to more fully understand the function of DC in polarized T cell response initiation with a view to improving vaccination or immuno-therapy strategies. .

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
1R01AI053825-01
Application #
6574061
Study Section
Tropical Medicine and Parasitology Study Section (TMP)
Program Officer
Wali, Tonu M
Project Start
2002-04-01
Project End
2006-03-31
Budget Start
2002-04-01
Budget End
2003-03-31
Support Year
1
Fiscal Year
2002
Total Cost
$351,676
Indirect Cost
Name
University of Pennsylvania
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Everts, Bart; Tussiwand, Roxane; Dreesen, Leentje et al. (2016) Migratory CD103+ dendritic cells suppress helminth-driven type 2 immunity through constitutive expression of IL-12. J Exp Med 213:35-51
Everts, Bart; Amiel, Eyal; Huang, Stanley Ching-Cheng et al. (2014) TLR-driven early glycolytic reprogramming via the kinases TBK1-IKK? supports the anabolic demands of dendritic cell activation. Nat Immunol 15:323-32
Amiel, Eyal; Everts, Bart; Fritz, Daniel et al. (2014) Mechanistic target of rapamycin inhibition extends cellular lifespan in dendritic cells by preserving mitochondrial function. J Immunol 193:2821-30
Amiel, Eyal; Everts, Bart; Freitas, Tori C et al. (2012) Inhibition of mechanistic target of rapamycin promotes dendritic cell activation and enhances therapeutic autologous vaccination in mice. J Immunol 189:2151-8
Everts, Bart; Amiel, Eyal; van der Windt, Gerritje J W et al. (2012) Commitment to glycolysis sustains survival of NO-producing inflammatory dendritic cells. Blood 120:1422-31
Everts, Bart; Hussaarts, Leonie; Driessen, Nicole N et al. (2012) Schistosome-derived omega-1 drives Th2 polarization by suppressing protein synthesis following internalization by the mannose receptor. J Exp Med 209:1753-67, S1
Thomas, Rajan M; Chen, Chunxia; Chunder, Neelanjana et al. (2010) Ikaros silences T-bet expression and interferon-gamma production during T helper 2 differentiation. J Biol Chem 285:2545-53
Krawczyk, Connie M; Holowka, Thomas; Sun, Jie et al. (2010) Toll-like receptor-induced changes in glycolytic metabolism regulate dendritic cell activation. Blood 115:4742-9
Nair, Meera G; Du, Yurong; Perrigoue, Jacqueline G et al. (2009) Alternatively activated macrophage-derived RELM-{alpha} is a negative regulator of type 2 inflammation in the lung. J Exp Med 206:937-52
Carvalho, Lucas; Sun, Jie; Kane, Colleen et al. (2009) Review series on helminths, immune modulation and the hygiene hypothesis: mechanisms underlying helminth modulation of dendritic cell function. Immunology 126:28-34

Showing the most recent 10 out of 28 publications