A genetic screen identifies a protective type III interferon response to Cryptosporidium that requires TLR3 dependent recognition

AbstractCryptosporidium is a leading cause of severe diarrhea and diarrheal-related death in children worldwide. As an obligate intracellular parasite, Cryptosporidium relies on intestinal epithelial cells to provide a niche for its growth and survival, but little is known about the contributions that the infected cell makes to this relationship. Here we conducted a genome wide CRISPR/Cas9 knockout screen to discover host genes required for Cryptosporidium parvum infection and/or host cell survival. Gene enrichment analysis indicated that the host interferon response, glycosaminoglycan (GAG) and glycosylphosphatidylinositol (GPI) anchor biosynthesis are important determinants of susceptibility to C. parvum infection. Several of these pathways are linked to parasite attachment and invasion and C-type lectins on the surface of the parasite. Evaluation of transcript and protein induction of innate interferons revealed a pronounced type III interferon response to Cryptosporidium in human cells as well as in mice. Treatment of mice with IFNλ reduced infection burden and protected immunocompromised mice from severe outcomes including death, with effects that required STAT1 signaling in the enterocyte. Initiation of this type III interferon response was dependent on sustained intracellular growth and mediated by the pattern recognition receptor TLR3. We conclude that host cell intrinsic recognition of Cryptosporidium results in IFNλ production critical to early protection against this infection.Author SummaryCryptosporidium infection is an important contributor to global childhood mortality. There are currently no vaccines available, and the only drug has limited efficacy in immunocompromised individuals and malnourished children who need it most. To discover which host proteins are essential for Cryptosporidium infection, we conducted a genome wide knockout screen in human host cells. Our results confirm the importance of glycosaminoglycans on the surface of epithelial cells for attachment and invasion of the parasite. We also found that host GPI anchor biosynthesis and interferon signaling pathways were enriched by our screen. Examining the role of interferon signaling further we found a type III interferon response, IFNλ, was generated in response to infection and shown to be initiated in the infected cell. Utilizing mouse models of infection, we found that the type III interferon response was important early during infection with its induction likely preceding IFNγ, a key cytokine for the control of this infection. We also determined that TLR3 was the pattern recognition receptor responsible for IFNλ production during Cryptosporidium infection. Our work shows that IFNλ acts directly on the enterocyte and its use in treating immunocompromised mice produced striking reductions in infection.

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Extremes of age are associated with differences in the expression of selected pattern recognition receptor genes and ACE2, the receptor for SARS-CoV-2: implications for the epidemiology of COVID-19 disease

BMC Medical Genomics ◽

10.1186/s12920-021-00970-7 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Stephen W. Bickler ◽

David M. Cauvi ◽

Kathleen M. Fisch ◽

James M. Prieto ◽

Alicia G. Sykes ◽

...

Keyword(s):

Pattern Recognition ◽

Dermal Fibroblasts ◽

Pattern Recognition Receptor ◽

Human Dermal Fibroblasts ◽

Rna Seq ◽

Large Dataset ◽

Genome Wide ◽

The Individual ◽

Recognition Receptor

Abstract Background Older aged adults and those with pre-existing conditions are at highest risk for severe COVID-19 associated outcomes. Methods Using a large dataset of genome-wide RNA-seq profiles derived from human dermal fibroblasts (GSE113957) we investigated whether age affects the expression of pattern recognition receptor (PRR) genes and ACE2, the receptor for SARS-CoV-2. Results Extremes of age are associated with increased expression of selected PRR genes, ACE2 and four genes that encode proteins that have been shown to interact with SAR2-CoV-2 proteins. Conclusions Assessment of PRR expression might provide a strategy for stratifying the risk of severe COVID-19 disease at both the individual and population levels.

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Regeneration After Radiation- and Immune-Mediated Tissue Injury Is Not Enhanced by Type III Interferon Signaling

International Journal of Radiation Oncology*Biology*Physics ◽

10.1016/j.ijrobp.2018.11.038 ◽

2019 ◽

Vol 103 (4) ◽

pp. 970-976 ◽

Cited By ~ 1

Author(s):

Julius C. Fischer ◽

Chia-Ching Lin ◽

Simon Heidegger ◽

Alexander Wintges ◽

Martin Schlapschy ◽

...

Keyword(s):

Tissue Injury ◽

Interferon Signaling ◽

Type Iii ◽

Immune Mediated ◽

Type Iii Interferon

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Rhinovirus-induced IFNβ expression is NFκB-dependent and regulated by the macrophage microenvironment

Scientific Reports ◽

10.1038/s41598-019-50034-1 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Mandy Menzel ◽

Joakim Kosinski ◽

Lena Uller ◽

Hamid Akbarshahi

Keyword(s):

Pattern Recognition ◽

Kinase Inhibitor ◽

Receptor Expression ◽

Interferon Response ◽

Murine Bone Marrow ◽

Gm Csf ◽

Protein Levels ◽

Iκb Kinase ◽

Viral Responses ◽

Recognition Receptor

Abstract Macrophages play an important role in asthma pathogenesis both in the inflammatory and resolution phase of the disease. Macrophages can acquire different polarisation states dependent on their microenvironment. It is yet unclear through which mechanism the microenvironment affects the anti-viral response in macrophages. We hypothesized that the macrophage microenvironment regulates rhinovirus-induced IFNβ expression. Murine bone marrow-derived monocytes and human differentiated THP-1 cells were stimulated with M-CSF or GM-CSF and IFNγ or IL-4/IL-13, respectively, to mimic a Th1 or Th2 environment. Macrophages were infected with rhinovirus and gene and protein levels of IFNβ and pattern recognition receptor expression were measured. In subsequent experiments an IκB kinase inhibitor was used to study the involvement of NFκB. Both murine and human M1-like macrophages exhibited higher levels of IFNβ and pattern recognition receptors after rhinovirus infection than M2-like macrophages. Blockage of NFκB resulted in a lower expression of rhinovirus-induced IFNβ in human M1-like macrophages while inducing a higher expression in M2-like macrophages, suggesting that the interferon response towards viral infection was mediated by NFκB. These findings could contribute to a better understanding of mechanisms causing reduced anti-viral responses at viral-induced exacerbations in asthma.

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Kinetic Differences and Synergistic Antiviral Effects Between Type I and Type III Interferon Signaling Indicate Pathway Independence

Journal of Interferon & Cytokine Research ◽

10.1089/jir.2015.0008 ◽

2015 ◽

Vol 35 (9) ◽

pp. 734-747 ◽

Cited By ~ 17

Author(s):

Emily A. Voigt ◽

John Yin

Keyword(s):

Type I ◽

Interferon Signaling ◽

Type Iii ◽

Antiviral Effects ◽

Type Iii Interferon

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XopC and XopJ, Two Novel Type III Effector Proteinsfrom Xanthomonas campestris pv.vesicatoria

Journal of Bacteriology ◽

10.1128/jb.185.24.7092-7102.2003 ◽

2003 ◽

Vol 185 (24) ◽

pp. 7092-7102 ◽

Cited By ~ 65

Author(s):

Laurent Noël ◽

Frank Thieme ◽

Jana Gäbler ◽

Daniela Büttner ◽

Ulla Bonas

Keyword(s):

Pseudomonas Syringae ◽

Plant Cell ◽

Type Iii Secretion ◽

Xanthomonas Campestris ◽

Pathogenic Bacteria ◽

Effector Proteins ◽

Type Iii ◽

Genome Wide ◽

A Genome ◽

Xanthomonas Campestris Pv.Vesicatoria

ABSTRACT Pathogenicity of the gram-negative plant pathogen Xanthomonas campestris pv. vesicatoria depends on a type III secretion (TTS) system which translocates bacterial effector proteins into the plant cell. Previous transcriptome analysis identified a genome-wide regulon of putative virulence genes that are coexpressed with the TTS system. In this study, we characterized two of these genes, xopC and xopJ. Both genes encode Xanthomonas outer proteins (Xops) that were shown to be secreted by the TTS system. In addition, type III-dependent translocation of both proteins into the plant cell was demonstrated using the AvrBs3 effector domain as a reporter. XopJ belongs to the AvrRxv/YopJ family of effector proteins from plant and animal pathogenic bacteria. By contrast, XopC does not share significant homology to proteins in the database. Sequence analysis revealed that the xopC locus contains several features that are reminiscent of pathogenicity islands. Interestingly, the xopC region is flanked by 62-bp inverted repeats that are also associated with members of the Xanthomonas avrBs3 effector family. Besides xopC, a second gene of the locus, designated hpaJ, was shown to be coexpressed with the TTS system. hpaJ encodes a protein with similarity to transglycosylases and to the Pseudomonas syringae pv. maculicola protein HopPmaG. HpaJ secretion and translocation by the X. campestris pv. vesicatoria TTS system was not detectable, which is consistent with its predicted Sec signal and a putative function as transglycosylase in the bacterial periplasm.

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