The lung is the critical site of entry for the most deadly form of anthrax infection, inhalation anthrax. Inhalation anthrax s relatively unique in that germinated vegetative bacteria of the etiologic agent of this disease, B.anthracis (Ba), do not cause disease at the site of entry. Instead Ba spores are taken up by resident lung cells and carried through lung ymphatic ducts to the thoracic lymph nodes (TLN), from which site Ba disseminates to cause the highly lethal, terminal phase of the disease. There remain many unanswered questions about this deadly disease. It is not known why vegetative Ba do not cause disease at the site of entry. It is not known what cells take the pathogen out of the lung to the TLN. Most importantly, it s not known what role Ba toxins (lethal toxin, LT;edema toxin, ET) play in this process. The overall goal of this proposal is to answer these questions. The current paradigm, based on mouse models and mouse cell lines, is that LT and ET do not play a significant role in the pathogenesis of inhalation anthrax. This may be correct for mice, but may not apply to humans. Mouse macrophage cell lines are very sensitive to the immunosuppressive effects of LT and express anthrax toxin receptors (ATR). In the last granting period we have determined that human alveolar macrophages (HAM) efficiently kill Ba vegetative bacteria, do not express ATR and are resistant to immunosuppressive effects of LT. We will test a new paradigm that holds that Ba toxins are very important in the early stages of inhalation anthrax and that the role of key lung cells is due to variable expression of the Ba toxins. We will test our new paradigm and answer the unanswered questions regarding inhalation anthrax in three Aims using a novel human lung organ culture model and a baboon inhalation model that is being developed by our colleague, Dr. Kurosawa. In the first Aim we will determine the human lung cells that internalize Ba and the state of the pathogen in these cells by exploiting our human lung organ culture model and by using flow cytometry, cell sorting, and quantitative confocal immunofluorescence microscopy. In the second Aim we will use a modification of the lung organ culture model, and tissue from Dr. Kurosawa's model to determine and confirm the cells that facilitate escape of Ba from the lung using techniques developed in the first Aim. In the final Aim, we will determine the role that Ba toxins play in inhalation anthrax, and whether downregulation of ATR in the lung organ culture model decreases internalization, survival and escape of the pathogen in human lung. This last set of experiments should provide a proof of concept to determine whether or not modulation of anthrax toxin receptors in human lung may be useful as preventative therapy for inhalation anthrax.

Public Health Relevance

Anthrax remains a significant bioterrorist health threat. The disease, when clinically apparent is extremely lethal, the spores are long lived and can be manufactured and distributed easily, the vaccine is difficult to administer, is associated with adverse effects and is not provided to the general public. Furthermore it is difficult to diagnose and thus treatment is often instituted too late to lead to cure. It is also relatively easy to distribute a large dose to an unsuspecting populous.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Program--Cooperative Agreements (U19)
Project #
2U19AI062629-06
Application #
7695607
Study Section
Special Emphasis Panel (ZAI1-KS-I (J3))
Project Start
2009-09-01
Project End
2014-08-31
Budget Start
2009-09-01
Budget End
2010-08-31
Support Year
6
Fiscal Year
2009
Total Cost
$375,738
Indirect Cost
Name
Oklahoma Medical Research Foundation
Department
Type
DUNS #
077333797
City
Oklahoma City
State
OK
Country
United States
Zip Code
73104
More, Sunil; Yang, Xiaoyun; Zhu, Zhengyu et al. (2018) Regulation of influenza virus replication by Wnt/?-catenin signaling. PLoS One 13:e0191010
Hu, Zihua; Jiang, Kaiyu; Frank, Mark Barton et al. (2018) Modeling Transcriptional Rewiring in Neutrophils Through the Course of Treated Juvenile Idiopathic Arthritis. Sci Rep 8:7805
Booth, J Leland; Duggan, Elizabeth S; Patel, Vineet I et al. (2018) Gene expression profiling of primary human type I alveolar epithelial cells exposed to Bacillus anthracis spores reveals induction of neutrophil and monocyte chemokines. Microb Pathog 121:9-21
Seshadri, Sudarshan; Pope, Rosemary L; Zenewicz, Lauren A (2018) Glucocorticoids Inhibit Group 3 Innate Lymphocyte IL-22 Production. J Immunol 201:1267-1274
Girton, Alanson W; Popescu, Narcis I; Keshari, Ravi S et al. (2018) Serum Amyloid P and IgG Exhibit Differential Capabilities in the Activation of the Innate Immune System in Response to Bacillus anthracis Peptidoglycan. Infect Immun 86:
Langer, Marybeth; Girton, Alanson W; Popescu, Narcis I et al. (2018) Neither Lys- and DAP-type peptidoglycans stimulate mouse or human innate immune cells via Toll-like receptor 2. PLoS One 13:e0193207
DeVette, Christa I; Andreatta, Massimo; Bardet, Wilfried et al. (2018) NetH2pan: A Computational Tool to Guide MHC Peptide Prediction on Murine Tumors. Cancer Immunol Res 6:636-644
Popescu, Narcis I; Silasi, Robert; Keshari, Ravi S et al. (2018) Peptidoglycan induces disseminated intravascular coagulation in baboons through activation of both coagulation pathways. Blood 132:849-860
Fuentes-Mattei, Enrique; Giza, Dana Elena; Shimizu, Masayoshi et al. (2017) Plasma Viral miRNAs Indicate a High Prevalence of Occult Viral Infections. EBioMedicine 20:182-192
Dumas, Eric K; Garman, Lori; Cuthbertson, Hannah et al. (2017) Lethal factor antibodies contribute to lethal toxin neutralization in recipients of anthrax vaccine precipitated. Vaccine 35:3416-3422

Showing the most recent 10 out of 121 publications