The oral cavity is a portal of entry for many infectious pathogens. However, despite advances in the field of mucosal immunity, mechanisms of immunity in the oral mucosa are surprisingly poorly understood. Whereas much of our understanding of mucosal immunity comes from studies of the gastrointestinal tract, immunity at other mucosal sites does not always parallel the gut. A good example of this dichotomy comes from studies of Candida albicans, a commensal dimorphic fungus that colonizes oral, esophageal and vaginal mucosal surfaces. In healthy individuals, C. albicans colonization is non-pathogenic. However, in conditions of immunodeficiency such as HIV/AIDS, Sj?gren's syndrome or congenital immunodeficiency, this microbe causes severe opportunistic infections of the oral cavity, known as """"""""thrush"""""""" or oropharyngeal candidiasis (OPC). The high incidence of OPC in HIV/AIDS (>90%) implicates CD4+ T cells in immunity against C. albicans. Until recently, this was thought to be the province of Th1 cells and their signature cytokine, IFNg. In 2005, a new subset of T cell was discovered that produces IL-17, and hence is known as """"""""Th17."""""""" IL-17-producing cells are highly enriched at mucosal surfaces, particularly the GI tract, and are selectively depleted in AIDS. In a gastrointestinal model of mucosal candidiasis, Th1 cells and IFNg appear to be host-protective, whereas IL-17 and the Th17-inductive cytokine IL-23 promote a deleterious immunopathology. In contrast, work from our group in mice and new studies in IL-17R-deficient humans indicate that IL-17 is an essential mediator of immunity against oral mucosal candidiasis. However, the specific mechanisms by which IL-17 drives host defense against Candida is not known, including the target cells within the oral mucosa or the downstream receptor signaling mechanisms mediated by the IL-17 receptor. The objective of this application is to fill this gap in our knowledge, by focusing specifically on the role of IL-1 and its receptor in mediating immune defense against Candida albicans in the oral cavity. To that end, we will use a series of gene-targeted mice to systematically define the important IL-17-responsive cell types in the context of OPC, and to delineate specific molecular signaling pathways used by the IL-17 receptor to mediate host defense.
Oral candidiasis, also known as oral thrush, is an AIDS-defining fungal infection of the oral mucosa. This disease also afflicts individuals on chemotherapy, transplant patients taking immunosuppressive drugs, asthma patients using inhaled corticosteroid drugs or others with compromised immune function such as infants and the elderly. The objective of this project is to understand in detail how the immune system normally keeps oral candidiasis under control, with an emphasis on the role of a particular cytokine receptor, the IL-17R. The long-term goal of this research is to develop better therapies or vaccines for mucosal disease of the oral cavity, and to understand the consequences of therapies that suppress specific immune events.
|Amatya, Nilesh; Childs, Erin E; Cruz, J Agustin et al. (2018) IL-17 integrates multiple self-reinforcing, feed-forward mechanisms through the RNA binding protein Arid5a. Sci Signal 11:|
|Verma, Akash H; Zafar, Hanna; Ponde, Nicole O et al. (2018) IL-36 and IL-1/IL-17 Drive Immunity to Oral Candidiasis via Parallel Mechanisms. J Immunol 201:627-634|
|Bichele, Rudolf; Kärner, Jaanika; Truusalu, Kai et al. (2018) IL-22 neutralizing autoantibodies impair fungal clearance in murine oropharyngeal candidiasis model. Eur J Immunol 48:464-470|
|Richardson, Jonathan P; Mogavero, Selene; Moyes, David L et al. (2018) Processing ofCandida albicansEce1p Is Critical for Candidalysin Maturation and Fungal Virulence. MBio 9:|
|Monin, Leticia; Gaffen, Sarah L (2018) Interleukin 17 Family Cytokines: Signaling Mechanisms, Biological Activities, and Therapeutic Implications. Cold Spring Harb Perspect Biol 10:|
|Amatya, Nilesh; Garg, Abhishek V; Gaffen, Sarah L (2017) IL-17 Signaling: The Yin and the Yang. Trends Immunol 38:310-322|
|Verma, Akash H; Richardson, Jonathan P; Zhou, Chunsheng et al. (2017) Oral epithelial cells orchestrate innate type 17 responses to Candida albicans through the virulence factor candidalysin. Sci Immunol 2:|
|Naglik, Julian R; König, Annika; Hube, Bernhard et al. (2017) Candida albicans-epithelial interactions and induction of mucosal innate immunity. Curr Opin Microbiol 40:104-112|
|Simpson-Abelson, Michelle R; Hernandez-Mir, Gerard; Childs, Erin E et al. (2017) CCAAT/Enhancer-binding protein ? promotes pathogenesis of EAE. Cytokine 92:24-32|
|Monin, Leticia; Gudjonsson, Johann E; Childs, Erin E et al. (2017) MCPIP1/Regnase-1 Restricts IL-17A- and IL-17C-Dependent Skin Inflammation. J Immunol 198:767-775|
Showing the most recent 10 out of 42 publications