Cytokine-induced, nitric oxide-dependent, intracellular antirickettsial activity of mouse endothelial cells

David Walker, Vsevolod Popov, Patricia A. Crocquet-Valdes, C. Jane R Welsh, Hui Min Feng

Research output: Contribution to journalArticle

79 Citations (Scopus)

Abstract

In a murine model of rickettsial disease in which, as in human rickettsioses, endothetial cells are the major target of infection, depletion of IFN-γ or TNF-α converts a sublethal infection into a uniformly fatal disease with overwhelming rickettsial growth and decreased nitric oxide (NO) synthesis. The kinetics of NO production and rickettsial survival end growth were examined on Days 1, 2, and 3 after inoculation of endothelial cells with Rickettsia conorii under four different experimental conditions: (a) no cytokine treatment, (b) treatment with IFN-γ and TNF-α, (c) treatment with eytokines and N(G) monomethyl-L-arginine, a competitive inhibitor of NO synthesis, and (d) treatment with sodium nitroprusside, a source of NO. Endothelial cells were examined for the presence of inducible nitric oxide synthase mRNA by specific reverse transcriptase-PCR after stimulation with IFN-γ and TNF-α. Cytokine-stimulated and unstimulated rickettsiae-infected endothelial cells were examined by electron microscopy to observe the cellular and rickettsial events. Transformed and diploid mouse endothelial cells stimulated by the combination of recombinant murine IFN-γ and TNE-α killed intracellular Rickettsia conorii by a mechanism that required the synthesis of NO. The antirickettsial effect and NO synthesis were inhibited by treatment of endothelial cells with N(G) monomethyl-L-arginine. Addition of nitroprusside, which released NO, also exerted a strong antirickettsial effect in the absence of IFN-γ and TNF-α. Endothelial inducible nitric oxide synthase mRNA was detected 4 hours after cytokine stimulation, increased substantially at 8 hours, and decreased to low levels by 72 hours. Ultrastructural evaluation revealed that endothelial cells effected rickettsial killing in association with autophagy. Double membranes of endothelial cell granular endoplasmic reticulum surrounded rickettsiae, which were also observed being destroyed within phagolysosomes. This study demonstrated for the first time that endothelial cells are capable of killing rickettsiae. When stimulated by the combination of IFN-γ and TNF-α, mouse endothelial cells kill Rickettsia conorii by an NO-dependent mechanism. Within the endothelium, NO exerts a rickettsicidal effect.

Original languageEnglish (US)
Pages (from-to)129-138
Number of pages10
JournalLaboratory Investigation
Volume76
Issue number1
StatePublished - Jan 1997

Fingerprint

Nitric Oxide
Endothelial Cells
Cytokines
Rickettsia conorii
Rickettsia
Nitroprusside
Nitric Oxide Synthase Type II
Arginine
Phagosomes
Messenger RNA
Rough Endoplasmic Reticulum
Nitric Oxide Synthase Type III
Autophagy
Growth
Infection
Reverse Transcriptase Polymerase Chain Reaction
Diploidy
Endothelium
Electron Microscopy
Membranes

ASJC Scopus subject areas

  • Pathology and Forensic Medicine

Cite this

Cytokine-induced, nitric oxide-dependent, intracellular antirickettsial activity of mouse endothelial cells. / Walker, David; Popov, Vsevolod; Crocquet-Valdes, Patricia A.; Welsh, C. Jane R; Feng, Hui Min.

In: Laboratory Investigation, Vol. 76, No. 1, 01.1997, p. 129-138.

Research output: Contribution to journalArticle

Walker, David ; Popov, Vsevolod ; Crocquet-Valdes, Patricia A. ; Welsh, C. Jane R ; Feng, Hui Min. / Cytokine-induced, nitric oxide-dependent, intracellular antirickettsial activity of mouse endothelial cells. In: Laboratory Investigation. 1997 ; Vol. 76, No. 1. pp. 129-138.
@article{4ed1eab7862e44a4aae3fe5234eda77d,
title = "Cytokine-induced, nitric oxide-dependent, intracellular antirickettsial activity of mouse endothelial cells",
abstract = "In a murine model of rickettsial disease in which, as in human rickettsioses, endothetial cells are the major target of infection, depletion of IFN-γ or TNF-α converts a sublethal infection into a uniformly fatal disease with overwhelming rickettsial growth and decreased nitric oxide (NO) synthesis. The kinetics of NO production and rickettsial survival end growth were examined on Days 1, 2, and 3 after inoculation of endothelial cells with Rickettsia conorii under four different experimental conditions: (a) no cytokine treatment, (b) treatment with IFN-γ and TNF-α, (c) treatment with eytokines and N(G) monomethyl-L-arginine, a competitive inhibitor of NO synthesis, and (d) treatment with sodium nitroprusside, a source of NO. Endothelial cells were examined for the presence of inducible nitric oxide synthase mRNA by specific reverse transcriptase-PCR after stimulation with IFN-γ and TNF-α. Cytokine-stimulated and unstimulated rickettsiae-infected endothelial cells were examined by electron microscopy to observe the cellular and rickettsial events. Transformed and diploid mouse endothelial cells stimulated by the combination of recombinant murine IFN-γ and TNE-α killed intracellular Rickettsia conorii by a mechanism that required the synthesis of NO. The antirickettsial effect and NO synthesis were inhibited by treatment of endothelial cells with N(G) monomethyl-L-arginine. Addition of nitroprusside, which released NO, also exerted a strong antirickettsial effect in the absence of IFN-γ and TNF-α. Endothelial inducible nitric oxide synthase mRNA was detected 4 hours after cytokine stimulation, increased substantially at 8 hours, and decreased to low levels by 72 hours. Ultrastructural evaluation revealed that endothelial cells effected rickettsial killing in association with autophagy. Double membranes of endothelial cell granular endoplasmic reticulum surrounded rickettsiae, which were also observed being destroyed within phagolysosomes. This study demonstrated for the first time that endothelial cells are capable of killing rickettsiae. When stimulated by the combination of IFN-γ and TNF-α, mouse endothelial cells kill Rickettsia conorii by an NO-dependent mechanism. Within the endothelium, NO exerts a rickettsicidal effect.",
author = "David Walker and Vsevolod Popov and Crocquet-Valdes, {Patricia A.} and Welsh, {C. Jane R} and Feng, {Hui Min}",
year = "1997",
month = "1",
language = "English (US)",
volume = "76",
pages = "129--138",
journal = "Laboratory Investigation",
issn = "0023-6837",
publisher = "Nature Publishing Group",
number = "1",

}

TY - JOUR

T1 - Cytokine-induced, nitric oxide-dependent, intracellular antirickettsial activity of mouse endothelial cells

AU - Walker, David

AU - Popov, Vsevolod

AU - Crocquet-Valdes, Patricia A.

AU - Welsh, C. Jane R

AU - Feng, Hui Min

PY - 1997/1

Y1 - 1997/1

N2 - In a murine model of rickettsial disease in which, as in human rickettsioses, endothetial cells are the major target of infection, depletion of IFN-γ or TNF-α converts a sublethal infection into a uniformly fatal disease with overwhelming rickettsial growth and decreased nitric oxide (NO) synthesis. The kinetics of NO production and rickettsial survival end growth were examined on Days 1, 2, and 3 after inoculation of endothelial cells with Rickettsia conorii under four different experimental conditions: (a) no cytokine treatment, (b) treatment with IFN-γ and TNF-α, (c) treatment with eytokines and N(G) monomethyl-L-arginine, a competitive inhibitor of NO synthesis, and (d) treatment with sodium nitroprusside, a source of NO. Endothelial cells were examined for the presence of inducible nitric oxide synthase mRNA by specific reverse transcriptase-PCR after stimulation with IFN-γ and TNF-α. Cytokine-stimulated and unstimulated rickettsiae-infected endothelial cells were examined by electron microscopy to observe the cellular and rickettsial events. Transformed and diploid mouse endothelial cells stimulated by the combination of recombinant murine IFN-γ and TNE-α killed intracellular Rickettsia conorii by a mechanism that required the synthesis of NO. The antirickettsial effect and NO synthesis were inhibited by treatment of endothelial cells with N(G) monomethyl-L-arginine. Addition of nitroprusside, which released NO, also exerted a strong antirickettsial effect in the absence of IFN-γ and TNF-α. Endothelial inducible nitric oxide synthase mRNA was detected 4 hours after cytokine stimulation, increased substantially at 8 hours, and decreased to low levels by 72 hours. Ultrastructural evaluation revealed that endothelial cells effected rickettsial killing in association with autophagy. Double membranes of endothelial cell granular endoplasmic reticulum surrounded rickettsiae, which were also observed being destroyed within phagolysosomes. This study demonstrated for the first time that endothelial cells are capable of killing rickettsiae. When stimulated by the combination of IFN-γ and TNF-α, mouse endothelial cells kill Rickettsia conorii by an NO-dependent mechanism. Within the endothelium, NO exerts a rickettsicidal effect.

AB - In a murine model of rickettsial disease in which, as in human rickettsioses, endothetial cells are the major target of infection, depletion of IFN-γ or TNF-α converts a sublethal infection into a uniformly fatal disease with overwhelming rickettsial growth and decreased nitric oxide (NO) synthesis. The kinetics of NO production and rickettsial survival end growth were examined on Days 1, 2, and 3 after inoculation of endothelial cells with Rickettsia conorii under four different experimental conditions: (a) no cytokine treatment, (b) treatment with IFN-γ and TNF-α, (c) treatment with eytokines and N(G) monomethyl-L-arginine, a competitive inhibitor of NO synthesis, and (d) treatment with sodium nitroprusside, a source of NO. Endothelial cells were examined for the presence of inducible nitric oxide synthase mRNA by specific reverse transcriptase-PCR after stimulation with IFN-γ and TNF-α. Cytokine-stimulated and unstimulated rickettsiae-infected endothelial cells were examined by electron microscopy to observe the cellular and rickettsial events. Transformed and diploid mouse endothelial cells stimulated by the combination of recombinant murine IFN-γ and TNE-α killed intracellular Rickettsia conorii by a mechanism that required the synthesis of NO. The antirickettsial effect and NO synthesis were inhibited by treatment of endothelial cells with N(G) monomethyl-L-arginine. Addition of nitroprusside, which released NO, also exerted a strong antirickettsial effect in the absence of IFN-γ and TNF-α. Endothelial inducible nitric oxide synthase mRNA was detected 4 hours after cytokine stimulation, increased substantially at 8 hours, and decreased to low levels by 72 hours. Ultrastructural evaluation revealed that endothelial cells effected rickettsial killing in association with autophagy. Double membranes of endothelial cell granular endoplasmic reticulum surrounded rickettsiae, which were also observed being destroyed within phagolysosomes. This study demonstrated for the first time that endothelial cells are capable of killing rickettsiae. When stimulated by the combination of IFN-γ and TNF-α, mouse endothelial cells kill Rickettsia conorii by an NO-dependent mechanism. Within the endothelium, NO exerts a rickettsicidal effect.

UR - http://www.scopus.com/inward/record.url?scp=0031035350&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0031035350&partnerID=8YFLogxK

M3 - Article

VL - 76

SP - 129

EP - 138

JO - Laboratory Investigation

JF - Laboratory Investigation

SN - 0023-6837

IS - 1

ER -