The long term objective of this proposal is to gain insight into mechanisms of host defense against infectious agents in humans, through the study of leprosy as a model. At the site of infection, organized collections of macrophages form granulomas to defend against the pathogen, Mycobacterium leprae. Our goal is to understand mechanisms of granuloma formation and function in human infectious disease. We will test the hypothesis that distinct subsets of macrophages regulate granuloma formation, and hence host defense. This will be accomplished by using bioengineered 3D microconstructs to encapsulate and confine M?, facilitating immune cell interaction, replicating the in vivo tissue microenvironment where granulomas form.
Our aims are: 1) Fabricate artificial granulomas using droplet microfluidics to model human leprosy infection, and, 2) Investigate the role of macrophage subsets in granuloma formation and function. In addition we will study the function of Langhans multinucleated giant cells, a hallmark of host defense in chronic infection. Together these aims target an integrated understanding of the interaction between a microbial pathogen and host-derived M?, with the goal to uncover novel mechanisms of immune responses that contain the pathogen, which might serve as targets host-directed therapies to modulate the immune response in human infectious disease. As such, this project brings together two laboratories, the Modlin lab with expertise in cellular immunology and the Revzin lab with expertise in bioengineering microstructures to optimize cell-cell interactions, to develop a new approach to study mechanisms by which granulomas are formed and contribute to host defense in humans.

Public Health Relevance

Our immune system must recognize and respond to microbes to combat infection. By studying leprosy, we propose to identify the types of immune responses that are generated, and the mechanism by which these immune responses are regulated. Insights into the host response to infection will provide new avenues for therapeutic intervention in infectious disease.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21AI121779-02
Application #
9260822
Study Section
Immunity and Host Defense (IHD)
Program Officer
Gondre-Lewis, Timothy A
Project Start
2016-04-15
Project End
2018-03-31
Budget Start
2017-04-01
Budget End
2018-03-31
Support Year
2
Fiscal Year
2017
Total Cost
$188,311
Indirect Cost
$33,750
Name
University of California Los Angeles
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
092530369
City
Los Angeles
State
CA
Country
United States
Zip Code
90095
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Lopez, David; Montoya, Dennis; Ambrose, Michael et al. (2017) SaVanT: a web-based tool for the sample-level visualization of molecular signatures in gene expression profiles. BMC Genomics 18:824
Scumpia, Philip O; Botten, Giovanni A; Norman, Joshua S et al. (2017) Opposing roles of Toll-like receptor and cytosolic DNA-STING signaling pathways for Staphylococcus aureus cutaneous host defense. PLoS Pathog 13:e1006496
Kibbie, Jon; Teles, Rosane M B; Wang, Zhiming et al. (2016) Jagged1 Instructs Macrophage Differentiation in Leprosy. PLoS Pathog 12:e1005808
Inkeles, Megan S; Teles, Rosane M B; Pouldar, Delila et al. (2016) Cell-type deconvolution with immune pathways identifies gene networks of host defense and immunopathology in leprosy. JCI Insight 1:e88843