The long term objective of this proposal is to gain insight into mechanisms of innate immunity to infectious agents in humans. Our discovery that TLR2 mediates the innate immune response to microbial lipoproteins, prompted us to investigate the regulation of innate immune response, finding that the selective induction of IL- 10 and IL 15, differentially programs macrophages for phagocytosis vs. antimicrobial responses in leprosy. The differential regulation of these pathways optimizes antimicrobial efficiency required for host defense against microbial pathogens, yet the divergence of these programs can also contribute to the pathogenesis of infectious disease. By investigating leprosy as a model, and its causative pathogen, Mycobacterium leprae (mLEP), we hope to gain insight into the innate immune mechanisms that instruct the macrophage functional programs that contribute to pathogenesis and host resistance. We therefore propose to: 1) determine the mechanisms by which mLEP, through distinct ligands, triggers innate immune receptors to differentially induce macrophage phagocytic and antimicrobial programs, 2) elucidate the mechanisms by which the local cytokine environment contributes to divergence of the macrophage functional programs in leprosy;and 3) investigate the mechanisms by which specific miRNAs regulate the phagocytic vs. antimicrobial innate immune responses in leprosy. Together these aims target an integrated understanding by which the innate immune response is programmed with relevance to host defense against microbial infection in humans, starting with the trigger (Aim 1), mechanisms of cytokine amplification (Aim 2) and molecular regulation (Aim 3) leading to the final functional programs at the site of infection in leprosy.

Public Health Relevance

Our immune system rapidly recognizes and responds to microbes to combat infection. By studying leprosy, we propose to identify the parts of microbes that are recognized by the immune system, 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
Research Project (R01)
Project #
5R01AI047868-15
Application #
8678815
Study Section
Clinical Research and Field Studies of Infectious Diseases Study Section (CRFS)
Program Officer
Davidson, Wendy F
Project Start
2000-09-01
Project End
2015-06-30
Budget Start
2014-07-01
Budget End
2015-06-30
Support Year
15
Fiscal Year
2014
Total Cost
Indirect Cost
Name
University of California Los Angeles
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
City
Los Angeles
State
CA
Country
United States
Zip Code
90095
Keegan, Caroline; Krutzik, Stephan; Schenk, Mirjam et al. (2018) Mycobacterium tuberculosis Transfer RNA Induces IL-12p70 via Synergistic Activation of Pattern Recognition Receptors within a Cell Network. J Immunol 200:3244-3258
Realegeno, Susan; Kelly-Scumpia, Kindra M; Dang, Angeline Tilly et al. (2016) S100A12 Is Part of the Antimicrobial Network against Mycobacterium leprae in Human Macrophages. PLoS Pathog 12:e1005705
Kibbie, Jon; Teles, Rosane M B; Wang, Zhiming et al. (2016) Jagged1 Instructs Macrophage Differentiation in Leprosy. PLoS Pathog 12:e1005808
Schenk, Mirjam; Mahapatra, Sebabrata; Le, Phuonganh et al. (2016) Human NOD2 Recognizes Structurally Unique Muramyl Dipeptides from Mycobacterium leprae. Infect Immun 84:2429-38
Meller, Stephan; Di Domizio, Jeremy; Voo, Kui S et al. (2015) T(H)17 cells promote microbial killing and innate immune sensing of DNA via interleukin 26. Nat Immunol 16:970-9
Cappuccio, Antonio; Zollinger, Raphaƫl; Schenk, Mirjam et al. (2015) Combinatorial code governing cellular responses to complex stimuli. Nat Commun 6:6847
Kim, Hee Jin; Brennan, Patrick J; Heaslip, Darragh et al. (2015) Carbohydrate-dependent binding of langerin to SodC, a cell wall glycoprotein of Mycobacterium leprae. J Bacteriol 197:615-25
Teles, Rosane M B; Kelly-Scumpia, Kindra M; Sarno, Euzenir N et al. (2015) IL-27 Suppresses Antimicrobial Activity in Human Leprosy. J Invest Dermatol 135:2410-2417
Ma, Feng; Liu, Su-Yang; Razani, Bahram et al. (2014) Retinoid X receptor ? attenuates host antiviral response by suppressing type I interferon. Nat Commun 5:5494
Montoya, Dennis; Inkeles, Megan S; Liu, Phillip T et al. (2014) IL-32 is a molecular marker of a host defense network in human tuberculosis. Sci Transl Med 6:250ra114

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