Allergic asthma is thought to stem from inappropriate immune responses to inhaled antigens. Therefore, to prevent or treat allergic asthma, it is important to identify the cellular and molecular mechanisms that initially give rise to allergic sensitization. Accordingly, our laboratory uses mouse models of asthma to study allergic sensitization through the airway. To do this, we sensitize mice to ovalbumin by delivering this protein to the airway together with low levels of lipopolysaccharide (LPS). Pulmonary dendritic cells that line the airway epithelium take up this antigen and migrate to draining thoracic lymph nodes to present OVA-derived peptides to nave T cells. We have found that this method of sensitization primes a qualitatively different type of immune response than the more conventional method of sensitization involving intraperitoneal (i.p.) injections of OVA complexed with aluminum hydroxide (alum). Thus, sensitization through the airway, but not through the peritoneum, induces robust T helper (Th)17 responses. These Th17 cells produce IL-17 upon challenge with OVA that in turn leads to airway neutrophilia and airway hyperresponsiveness (AHR). Ongoing Th17 responses to inhaled allergens might therefore distinguish severe asthma from less serious Th2-mediated diseases of the airway.? ? In addition to studying the mechanisms underlying the induction of Th17 cells in the lung, we also study the impact of various environmental pollutants on pulmonary dendritic cell activation, and how these pollutants can act as adjuvants in the lung to promote allergic sensitization through the airway.? ? The molecules that direct homing of antigen-specific T cells to the lung have not been identified. We seek to identify these molecules by culturing pulmonary dendritic cells with OVA-specific T cells from OT-II mice.? ? Pulmonary dendritic cells are thought to arise from monocytes that arrive in the lung from the blood. Although the chemokine receptors, CCR2 and CX3CR1 have both been implicated in the recruitment of monocytes to the lung, it is still unclear whether monocytes displaying these two molecules give rise to pulmonary dendritic cells having different functional properties. One of the projects in our laboratory is directed at identifying such differences.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Intramural Research (Z01)
Project #
1Z01ES102025-03
Application #
7734552
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
3
Fiscal Year
2008
Total Cost
$1,691,556
Indirect Cost
City
State
Country
United States
Zip Code
Zhang, Song; Takaku, Motoki; Zou, Liyun et al. (2017) Reversing SKI-SMAD4-mediated suppression is essential for TH17 cell differentiation. Nature 551:105-109
Wilson, Rhonda H; Whitehead, Gregory S; Nakano, Hideki et al. (2009) Allergic sensitization through the airway primes Th17-dependent neutrophilia and airway hyperresponsiveness. Am J Respir Crit Care Med 180:720-30
Cook, Donald N; Bottomly, Kim (2007) Innate immune control of pulmonary dendritic cell trafficking. Proc Am Thorac Soc 4:234-9
Whitehead, Gregory S; Wang, Tie; DeGraff, Laura M et al. (2007) The chemokine receptor D6 has opposing effects on allergic inflammation and airway reactivity. Am J Respir Crit Care Med 175:243-9
Martinez de la Torre, Yeny; Buracchi, Chiara; Borroni, Elena M et al. (2007) Protection against inflammation- and autoantibody-caused fetal loss by the chemokine decoy receptor D6. Proc Natl Acad Sci U S A 104:2319-24
Garantziotis, Stavros; Palmer, Scott M; Snyder, Laurie D et al. (2007) Alloimmune lung injury induced by local innate immune activation through inhaled lipopolysaccharide. Transplantation 84:1012-9
Wen, Haitao; Hogaboam, Cory M; Lukacs, Nicholas W et al. (2007) The chemokine receptor CCR6 is an important component of the innate immune response. Eur J Immunol 37:2487-98
Cardona, Astrid E; Pioro, Erik P; Sasse, Margaret E et al. (2006) Control of microglial neurotoxicity by the fractalkine receptor. Nat Neurosci 9:917-24
Liu, LiPing; Graham, Gerard J; Damodaran, Anita et al. (2006) Cutting edge: the silent chemokine receptor D6 is required for generating T cell responses that mediate experimental autoimmune encephalomyelitis. J Immunol 177:17-21
Hollingsworth, John W; Whitehead, Gregory S; Lin, Kaifeng Lisa et al. (2006) TLR4 signaling attenuates ongoing allergic inflammation. J Immunol 176:5856-62

Showing the most recent 10 out of 16 publications