Burkholderia pseudomallei triggers canonical inflammasome activation in a human primary macrophage-based infection model.
Most of the current knowledge on Burkholderia pseudomallei-induced inflammasome activation and cell death in macrophages is derived from murine systems. Little is known about the involved bacterial structures and mechanisms in primary human macrophages. This is of particular relevance since murine a...
Published in: | PLOS Neglected Tropical Diseases |
---|---|
Main Authors: | , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Public Library of Science (PLoS)
2020
|
Subjects: | |
Online Access: | https://doi.org/10.1371/journal.pntd.0008840 https://doaj.org/article/b6847a495f534362b08508c603985871 |
id |
ftdoajarticles:oai:doaj.org/article:b6847a495f534362b08508c603985871 |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:b6847a495f534362b08508c603985871 2023-05-15T15:15:30+02:00 Burkholderia pseudomallei triggers canonical inflammasome activation in a human primary macrophage-based infection model. Sabine Lichtenegger Julia Stiehler Sabine Saiger Andrea Zauner Barbara Kleinhappl Claudia Bernecker Peter Schlenke Gabriel E Wagner Kathrin Krause Magdalena Gastager Ivo Steinmetz 2020-11-01T00:00:00Z https://doi.org/10.1371/journal.pntd.0008840 https://doaj.org/article/b6847a495f534362b08508c603985871 EN eng Public Library of Science (PLoS) https://doi.org/10.1371/journal.pntd.0008840 https://doaj.org/toc/1935-2727 https://doaj.org/toc/1935-2735 1935-2727 1935-2735 doi:10.1371/journal.pntd.0008840 https://doaj.org/article/b6847a495f534362b08508c603985871 PLoS Neglected Tropical Diseases, Vol 14, Iss 11, p e0008840 (2020) Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 article 2020 ftdoajarticles https://doi.org/10.1371/journal.pntd.0008840 2022-12-31T07:36:41Z Most of the current knowledge on Burkholderia pseudomallei-induced inflammasome activation and cell death in macrophages is derived from murine systems. Little is known about the involved bacterial structures and mechanisms in primary human macrophages. This is of particular relevance since murine and human macrophages as well as primary cells and cell lines differ in many aspects of inflammasome activation, including the proteins involved in the recognition of bacterial patterns. In this study, we therefore aimed (i) to establish an in vitro B. pseudomallei infection model with human monocyte-derived primary macrophages from single donors as these cells more closely resemble macrophages in the human host and (ii) to analyze B. pseudomallei-triggered cell death and bacterial elimination in those cells. Our results show that B. pseudomallei-infected primary human macrophages not only release the inflammasome-independent pro-inflammatory cytokines IL-8 and TNF-α, but are also engaged in canonical inflammasome activation as evidenced by caspase-1 and gasdermin D processing. Absence of the B. pseudomallei T3SS-3 needle protein BsaL, a potent activator of the canonical inflammasome, abolished lytic cell death, reduced IL-1β release, and caspase-1 and gasdermin D processing. IFN-γ, known to promote non-canonical inflammasome activation, did not influence pyroptosis induction or IL-1β release from infected primary human macrophages. Nevertheless, it reduced intracellular B. pseudomallei loads, an effect which was partially antagonist by the inhibition of NADPH oxidase. Overall, our data implicate T3SS-3 dependent inflammasome activation and IFN-γ induced immune mechanisms as critical defense mechanisms of human macrophages against B. pseudomallei. In addition, our infection model provides a versatile tool to study human host-pathogen interactions and has the potential to elucidate the role of human individual genetic variations in B. pseudomallei infections. Article in Journal/Newspaper Arctic Directory of Open Access Journals: DOAJ Articles Arctic PLOS Neglected Tropical Diseases 14 11 e0008840 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
spellingShingle |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 Sabine Lichtenegger Julia Stiehler Sabine Saiger Andrea Zauner Barbara Kleinhappl Claudia Bernecker Peter Schlenke Gabriel E Wagner Kathrin Krause Magdalena Gastager Ivo Steinmetz Burkholderia pseudomallei triggers canonical inflammasome activation in a human primary macrophage-based infection model. |
topic_facet |
Arctic medicine. Tropical medicine RC955-962 Public aspects of medicine RA1-1270 |
description |
Most of the current knowledge on Burkholderia pseudomallei-induced inflammasome activation and cell death in macrophages is derived from murine systems. Little is known about the involved bacterial structures and mechanisms in primary human macrophages. This is of particular relevance since murine and human macrophages as well as primary cells and cell lines differ in many aspects of inflammasome activation, including the proteins involved in the recognition of bacterial patterns. In this study, we therefore aimed (i) to establish an in vitro B. pseudomallei infection model with human monocyte-derived primary macrophages from single donors as these cells more closely resemble macrophages in the human host and (ii) to analyze B. pseudomallei-triggered cell death and bacterial elimination in those cells. Our results show that B. pseudomallei-infected primary human macrophages not only release the inflammasome-independent pro-inflammatory cytokines IL-8 and TNF-α, but are also engaged in canonical inflammasome activation as evidenced by caspase-1 and gasdermin D processing. Absence of the B. pseudomallei T3SS-3 needle protein BsaL, a potent activator of the canonical inflammasome, abolished lytic cell death, reduced IL-1β release, and caspase-1 and gasdermin D processing. IFN-γ, known to promote non-canonical inflammasome activation, did not influence pyroptosis induction or IL-1β release from infected primary human macrophages. Nevertheless, it reduced intracellular B. pseudomallei loads, an effect which was partially antagonist by the inhibition of NADPH oxidase. Overall, our data implicate T3SS-3 dependent inflammasome activation and IFN-γ induced immune mechanisms as critical defense mechanisms of human macrophages against B. pseudomallei. In addition, our infection model provides a versatile tool to study human host-pathogen interactions and has the potential to elucidate the role of human individual genetic variations in B. pseudomallei infections. |
format |
Article in Journal/Newspaper |
author |
Sabine Lichtenegger Julia Stiehler Sabine Saiger Andrea Zauner Barbara Kleinhappl Claudia Bernecker Peter Schlenke Gabriel E Wagner Kathrin Krause Magdalena Gastager Ivo Steinmetz |
author_facet |
Sabine Lichtenegger Julia Stiehler Sabine Saiger Andrea Zauner Barbara Kleinhappl Claudia Bernecker Peter Schlenke Gabriel E Wagner Kathrin Krause Magdalena Gastager Ivo Steinmetz |
author_sort |
Sabine Lichtenegger |
title |
Burkholderia pseudomallei triggers canonical inflammasome activation in a human primary macrophage-based infection model. |
title_short |
Burkholderia pseudomallei triggers canonical inflammasome activation in a human primary macrophage-based infection model. |
title_full |
Burkholderia pseudomallei triggers canonical inflammasome activation in a human primary macrophage-based infection model. |
title_fullStr |
Burkholderia pseudomallei triggers canonical inflammasome activation in a human primary macrophage-based infection model. |
title_full_unstemmed |
Burkholderia pseudomallei triggers canonical inflammasome activation in a human primary macrophage-based infection model. |
title_sort |
burkholderia pseudomallei triggers canonical inflammasome activation in a human primary macrophage-based infection model. |
publisher |
Public Library of Science (PLoS) |
publishDate |
2020 |
url |
https://doi.org/10.1371/journal.pntd.0008840 https://doaj.org/article/b6847a495f534362b08508c603985871 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic |
genre_facet |
Arctic |
op_source |
PLoS Neglected Tropical Diseases, Vol 14, Iss 11, p e0008840 (2020) |
op_relation |
https://doi.org/10.1371/journal.pntd.0008840 https://doaj.org/toc/1935-2727 https://doaj.org/toc/1935-2735 1935-2727 1935-2735 doi:10.1371/journal.pntd.0008840 https://doaj.org/article/b6847a495f534362b08508c603985871 |
op_doi |
https://doi.org/10.1371/journal.pntd.0008840 |
container_title |
PLOS Neglected Tropical Diseases |
container_volume |
14 |
container_issue |
11 |
container_start_page |
e0008840 |
_version_ |
1766345874440454144 |