Approximately one-fourth of the world's population is latently infected (LTBI) with Mycobacterium tuberculosis (Mtb) and those infected have a 10% lifetime risk of developing clinical pulmonary TB (PTB) disease over their lifetime. Global efforts to combat TB are hampered by the emergence of extensively drug-resistant and multidrug- resistant strains and the variable efficacy of the currently available vaccine, M. bovis Bacille Calmette Guerin. Unfortunately, the immune mechanisms that govern progression from LTBI to PTB are poorly defined, preventing rational design of treatments or vaccines that stimulate immune control of TB. Thus, there is an urgent need to better understand the immune parameters that contribute to Mtb control. The tubercle granuloma is a hallmark of TB and is important for the immune control of Mtb infection. However, not all granulomas effectively control TB, as they are seen both during LTBI and during TB reactivation (TB-R) and PTB. During the previous R01 funding period, we used human TB samples and non-human primate (NHP) and mouse models of TB to demonstrate an unequivocal protective role for inducible bronchus-associated lymphoid tissue (iBALT) containing clearly defined B-cell follicles during both primary and vaccine-induced responses to Mtb infection. Additionally, we determined that a dominant feature of granulomas during PTB is the accumulation of neutrophils that produce proinflammatory molecules such as S100A8/A9 proteins and limit iBALT formation. Our long-term goal is to develop clinical strategies to restrain Mtb growth and prevent progression from LTBI to TB disease. Based on work from this funded R01, the objective of this R01 renewal is to identify the roles of granuloma- associated B cells and neutrophils in TB infection and disease progression and to determine if iBALT is an effective target for preventing TB progression. Towards this overall goal, we propose to use both small animal and large animal models to address the following specific aims:
In Specific Aim 1 we will investigate the role of iBALT-residing B cells in protecting against TB;
In Specific Aim 2, we will evaluate the role of neutrophilic proteins such as S100A8/A9 in limiting iBALT during PTB, and to determine if targeting S100A8/A9 pathways will reduce TB disease and improve Mtb control; Finally, in Specific Aim 3, we will determine if iBALT structures can be targeted to prevent TB progression in Mtb-infected hosts. The knowledge to be gained from these studies is significant, as it will directly advance the development of new therapeutics and vaccine strategies for limiting TB-R and progression to TB.

Public Health Relevance

Mycobacterium tuberculosis (Mtb), the causative agent of the disease tuberculosis (TB), is estimated to infect one-fourth of the world's population, resulting in approximately 1.6 million deaths each year. There is a critical need to better understand the mechanisms of TB immunopathogenesis, as such mechanisms can be targeted to improve host control of Mtb infection. The work proposed in this R01 renewal will further elucidate the mechanisms by which inducible Bronchus Associated Lymphoid Tissue (iBALT) - containing granulomas confer protection against TB and will test approaches for clinically improving iBALT formation and limiting neutrophil accumulation. The knowledge to be gained from these studies is significant, as it will advance the development of new therapeutics and vaccine strategies for limiting TB reactivation and progression to TB.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
2R01AI111914-06A1
Application #
10223661
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Eichelberg, Katrin
Project Start
2015-04-01
Project End
2026-01-31
Budget Start
2021-02-15
Budget End
2022-01-31
Support Year
6
Fiscal Year
2021
Total Cost
Indirect Cost
Name
Washington University
Department
Microbiology/Immun/Virology
Type
Schools of Medicine
DUNS #
068552207
City
Saint Louis
State
MO
Country
United States
Zip Code
63130
Gautam, Uma S; Foreman, Taylor W; Bucsan, Allison N et al. (2018) In vivo inhibition of tryptophan catabolism reorganizes the tuberculoma and augments immune-mediated control of Mycobacterium tuberculosis. Proc Natl Acad Sci U S A 115:E62-E71
Dunlap, Micah D; Howard, Nicole; Das, Shibali et al. (2018) A novel role for C-C motif chemokine receptor 2 during infection with hypervirulent Mycobacterium tuberculosis. Mucosal Immunol 11:1727-1742
Sundar, Isaac K; Rashid, Kahkashan; Gerloff, Janice et al. (2018) Genetic ablation of histone deacetylase 2 leads to lung cellular senescence and lymphoid follicle formation in COPD/emphysema. FASEB J 32:4955-4971
Howard, Nicole C; Marin, Nancy D; Ahmed, Mushtaq et al. (2018) Mycobacterium tuberculosis carrying a rifampicin drug resistance mutation reprograms macrophage metabolism through cell wall lipid changes. Nat Microbiol 3:1099-1108
Eddens, Taylor; Elsegeiny, Waleed; Garcia-Hernadez, Maria de la Luz et al. (2017) Pneumocystis-Driven Inducible Bronchus-Associated Lymphoid Tissue Formation Requires Th2 and Th17 Immunity. Cell Rep 18:3078-3090
Foreman, Taylor W; Veatch, Ashley V; LoBato, Denae N et al. (2017) Nonpathologic Infection of Macaques by an Attenuated Mycobacterial Vaccine Is Not Reactivated in the Setting of HIV Co-Infection. Am J Pathol 187:2811-2820
Treerat, P; Prince, O; Cruz-Lagunas, A et al. (2017) Novel role for IL-22 in protection during chronic Mycobacterium tuberculosis HN878 infection. Mucosal Immunol 10:1069-1081
Das, Shibali; Khader, Shabaana (2017) Yin and yang of interleukin-17 in host immunity to infection. F1000Res 6:741
Foreman, Taylor W; Mehra, Smriti; LoBato, Denae N et al. (2016) CD4+ T-cell-independent mechanisms suppress reactivation of latent tuberculosis in a macaque model of HIV coinfection. Proc Natl Acad Sci U S A 113:E5636-44
Domingo-Gonzalez, Racquel; Prince, Oliver; Cooper, Andrea et al. (2016) Cytokines and Chemokines in Mycobacterium tuberculosis Infection. Microbiol Spectr 4:

Showing the most recent 10 out of 11 publications