Cryptococcus neoformans is a common and devastating opportunistic fungal pathogen that causes substantial mortality worldwide. Current therapies for veterans infected with C. neoformans or related fungal pathogens are lengthy, frequently toxic, and often ineffective. Generation and maintenance of this type 1 or classically-activated immune response over extended time is required to achieve complete clearance of C. neoformans and to prevent the all too common development of persistent infection and/or relapses. One of the side effects of the increasingly prescribed anti-inflammatory TNF?eutralizing monoclonal antibody therapy is susceptibility to fungal infections (including C. neoformans). Our preliminary data strongly suggest that TNF?s a central molecule required for programing of type 1 dendritic cell (DC1) and the subsequent development of a stable, protective Th1/Th17 response. The present studies are designed to determine how TNF?ontributes to programming of myeloid DC to sustain a protective Th1/Th17 response throughout the extended time period required for clearance of C. neoformans. Hypothesis: Our central hypothesis is that effective clearance of C. neoformans requires the TNF?ediated DC1 programming of myeloid DC to sustain a protective Th1/Th17 response throughout the extended time period required for clearance of C. neoformans. We further hypothesize that TNF?ignaling in DC and/or their myeloid precursors contributes to execution of epigenetic modifications that support stability of the DC1 phenotype and prevents the development of a DC2 phenotype. The following aims have been constructed to rigorously test this hypothesis.
Aim 1 : To determine whether TNF?s required for stable DC1-programing during the protective response to cryptococcal infection.
Aim 2 : To determine if TNF?ediates epigenetic programing of the DC1 phenotype in myeloid precursors and/or DC in C. neoformans infected lungs.
Aim 3 : To determine whether TNF?nduced DC1 programming is necessary and sufficient for generating protective immune responses to C. neoformans. Research Plan and Methods: Our proposal utilizes highly translational model of infection of CBA/J mice with the moderately virulent C. neoformans strain 24067 and series of in vitro studies that will define the effects of transient TNF?epletion using one dose of monoclonal antibodies at the time of infection. These studies will allow us to define whether, and to what degree, TNF?nduces stability of the DC1 program. We will define at which stage of DC development (bone marrow precursor, DC differentiation or maturation) TNF?tabilizes DC. We will determine whether the DC1 phenotype stability can be attributed to changes in enzymes responsible for epigenetic chromatin modification and resultant changes in histone methylation signatures at gene promoter regions crucial for execution of DC1 program. The contribution of DC and their myeloid precursors to the execution of stable protective immune responses in the lungs will be then tested in a series of adoptive transfer experiments. Completion of these studies will demonstrate a novel role of TNF?n stabilization of a protective immune response to C. neoformans. This translational study will provide a link between epigenetic chromatin modification and biological effects of TNF?n vivo and provide an insight into a potential mechanism of increased risk of fungal infections in patients treated with anti-TNF?ntibodies, which our lab's mouse model very effectively mimics.

Public Health Relevance

Fungal lung infections are a major source of morbidity and mortality in veterans with compromised immune systems as a result of AIDS, substance abuse, or stemming from treatment of malignancy, auto-immune disease, or organ transplantation. Persistent fungal lung infections in immunocompetent or mildly immunocompromised veterans results in chronic lung disease. Antibiotic therapy is often inadequate; thus knowledge of pulmonary host defense is of central importance to the development of new therapies or vaccine strategies to treat this patient population. This project also has the potential to provide answers relevant to other chronic infections, notably tuberculosis; to how tumors subvert innate immunity to serve rather than eliminate cancers; and to the mechanisms by which lung dendritic cells in individual atopic subjects do or don't drive the development of asthma.

Agency
National Institute of Health (NIH)
Institute
Veterans Affairs (VA)
Type
Non-HHS Research Projects (I01)
Project #
5I01BX000656-07
Application #
9281605
Study Section
Infectious Diseases B (INFB)
Project Start
2009-10-01
Project End
2018-12-31
Budget Start
2017-01-01
Budget End
2017-12-31
Support Year
7
Fiscal Year
2017
Total Cost
Indirect Cost
Name
Veterans Health Administration
Department
Type
DUNS #
096318480
City
Ann Arbor
State
MI
Country
United States
Zip Code
48105
Teitz-Tennenbaum, Seagal; Viglianti, Steven P; Roussey, Jonathan A et al. (2018) Autocrine IL-10 Signaling Promotes Dendritic Cell Type-2 Activation and Persistence of Murine Cryptococcal Lung Infection. J Immunol 201:2004-2015
So, Yee-Seul; Jang, Juyeong; Park, Goun et al. (2018) Sho1 and Msb2 Play Complementary but Distinct Roles in Stress Responses, Sexual Differentiation, and Pathogenicity of Cryptococcus neoformans. Front Microbiol 9:2958
Wang, Shiwen; Yang, Feng; Li, Dong et al. (2018) Clinical application of a multiplex genetic pathogen detection system remaps the aetiology of diarrhoeal infections in Shanghai. Gut Pathog 10:37
Neal, Lori M; Xing, Enze; Xu, Jintao et al. (2017) CD4+ T Cells Orchestrate Lethal Immune Pathology despite Fungal Clearance during Cryptococcus neoformans Meningoencephalitis. MBio 8:
Xu, Jintao; Flaczyk, Adam; Neal, Lori M et al. (2017) Scavenger Receptor MARCO Orchestrates Early Defenses and Contributes to Fungal Containment during Cryptococcal Infection. J Immunol 198:3548-3557
Roussey, Jonathan A; Viglianti, Steven P; Teitz-Tennenbaum, Seagal et al. (2017) Anti-PD-1 Antibody Treatment Promotes Clearance of Persistent Cryptococcal Lung Infection in Mice. J Immunol 199:3535-3546
Xu, Jintao; Flaczyk, Adam; Neal, Lori M et al. (2017) Exploitation of Scavenger Receptor, Macrophage Receptor with Collagenous Structure, by Cryptococcus neoformans Promotes Alternative Activation of Pulmonary Lymph Node CD11b+ Conventional Dendritic Cells and Non-Protective Th2 Bias. Front Immunol 8:1231
Neal, Lori M; Qiu, Yafeng; Chung, Jooho et al. (2017) T Cell-Restricted Notch Signaling Contributes to Pulmonary Th1 and Th2 Immunity during Cryptococcus neoformans Infection. J Immunol 199:643-655
Malachowski, Antoni N; Yosri, Mohamed; Park, Goun et al. (2016) Systemic Approach to Virulence Gene Network Analysis for Gaining New Insight into Cryptococcal Virulence. Front Microbiol 7:1652
Zhang, Yanmei; Wang, Shiwen; Hu, Binjie et al. (2016) Direct detection of Helicobacter pylori in biopsy specimens using a high-throughput multiple genetic detection system. Future Microbiol 11:1521-1534

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