Parasitic helminths exhibit the remarkable ability to establish chronic, often lifelong, infections by triggering multiple mechanisms to dampen the host immune response. These immunoregulatory pathways protect the host from excessive infection-induced tissue damage, and can be exploited for new therapies to treat inflammation. Using transgenic mice that express human resistin (hRetn) and Nippostrongylus brasiliensis as a mouse model of geohelminth infection, we identified hRetn as an immunomodulatory protein that impaired helminth expulsion but was critically protective in a mouse model of sepsis involving injection of a fatal dose of LPS. Mechanistically, hRetn bound the LPS receptor TLR4 and inhibited LPS binding and signaling. Based on these results, we hypothesize that the function of helminth-induced resistin is to dampen excessive LPS-induced inflammatory responses, which may arise from helminth- induced tissue damage or sepsis. We propose to elucidate the mechanism by which helminth- induced hRetn protects against sepsis and generate new hRetn fusion proteins to treat LPS- induced inflammation.
In Aim 1, we will examine how helminth-induced hRetn regulates LPS- induced pathogenesis and if this regulatory pathway is dependent on TLR4.
In Aim 2, we will generate new hRetn proteins fused with human Fc immunoglobulin and hRetn peptides that can be used therapeutically to treat sepsis.

Public Health Relevance

Parasitic helminths trigger multiple immunoregulatory pathways to prevent their own expulsion that can be harnessed to treat inflammation. We identify human resistin as a helminth-induced protein that prevents endotoxic shock, and will elucidate this anti- inflammatory pathway and test new resistin reagents to treat endotoxic shock. Identifying new regulators of LPS-induced inflammation has therapeutic implications for several inflammatory diseases beyond helminth infection, including sepsis.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21AI137830-02
Application #
9614890
Study Section
Immunity and Host Defense (IHD)
Program Officer
Singleton, Kentner L
Project Start
2017-12-15
Project End
2020-11-30
Budget Start
2018-12-01
Budget End
2020-11-30
Support Year
2
Fiscal Year
2019
Total Cost
Indirect Cost
Name
University of California Riverside
Department
Type
Schools of Medicine
DUNS #
627797426
City
Riverside
State
CA
Country
United States
Zip Code
92521
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Batugedara, Hashini M; Argueta, Donovan; Jang, Jessica C et al. (2018) Host- and Helminth-Derived Endocannabinoids That Have Effects on Host Immunity Are Generated during Infection. Infect Immun 86:
Jang, Jessica C; Li, Jiang; Gambini, Luca et al. (2017) Human resistin protects against endotoxic shock by blocking LPS-TLR4 interaction. Proc Natl Acad Sci U S A 114:E10399-E10408