» Articles » PMID: 24932221

The Impact of Toll-like-receptor-9 on Intestinal Microbiota Composition and Extra-intestinal Sequelae in Experimental Toxoplasma Gondii Induced Ileitis

Overview
Journal Gut Pathog
Publisher Biomed Central
Specialty Gastroenterology
Date 2014 Jun 17
PMID 24932221
Citations 31
Authors
Affiliations
Soon will be listed here.
Abstract

Background: Following peroral Toxoplasma (T.) gondii infection, susceptible mice develop acute ileitis due to a microbiota-dependent Th1 type immunopathology. Toll-like-receptor (TLR)-9 is known to recognize bacterial DNA and mediates intestinal inflammation, but its impact on intestinal microbiota composition and extra-intestinal sequelae following T. gondii infection has not yet been elucidated.

Methods And Results: Seven days following peroral infection (p.i.) with 100 cysts of T. gondii ME49 strain, TLR-9(-/-) and wildtype (WT) mice suffered from comparable ileitis, whereas ileal parasitic loads as well as IFN-γ and nitric oxide levels were higher in TLR-9(-/-) compared to WT mice. Locally, TLR-9(-/-) mice exhibited increased ileal CD3+, but not FOXP3+ cell numbers at day 7 p.i.; in mesenteric lymph nodes IFN-γ-producing CD4+ cell numbers and TNF-α and IFN-γ concentrations were also increased in TLR-9(-/-) compared to WT mice. T. gondii DNA levels, however, did not differ in mice of either genotype. Differences in intestinal microbiota were rather subtle except for bifidobacteria that were virtually absent in both, naïve and T. gondii infected TLR-9(-/-), but not WT mice. Extra-intestinally, TLR-9(-/-) mice displayed less distinct systemic immune responses as indicated by lower serum IL-6, and splenic TNF-α and IFN-γ levels as compared to WT mice despite higher translocation rates of intestinal bacteria to extra-intestinal compartments such as liver, spleen, kidney, and cardiac blood. Most importantly, brains were also affected in this inflammatory scenario as early as day 7 p.i. Remarkably, TLR-9(-/-) mice exhibited more pronounced inflammatory infiltrates with higher numbers of F4/80+ macrophages and microglia in the cortex and meninges as compared to WT mice, whereas T. gondii DNA levels did not differ.

Conclusion: We here show that TLR-9 is not required for the development of T. gondii induced ileitis but mediates distinct inflammatory changes in intestinal and extra-intestinal compartments including the brain.

Citing Articles

Pathological mechanisms of glial cell activation and neurodegenerative and neuropsychiatric disorders caused by infection.

Yang Z, Chen J, Zhang C, Peng H Front Microbiol. 2024; 15:1512233.

PMID: 39723133 PMC: 11668811. DOI: 10.3389/fmicb.2024.1512233.


Toxoplasma-induced behavior changes - is microbial dysbiosis the missing link?.

Prandovszky E, Severance E, Splan V, Liu H, Xiao J, Yolken R Front Cell Infect Microbiol. 2024; 14:1415079.

PMID: 39403206 PMC: 11471644. DOI: 10.3389/fcimb.2024.1415079.


P2X7 Receptor Modulation of the Gut Microbiota and the Inflammasome Determines the Severity of -Induced Ileitis.

Moreira-Souza A, Nanini H, Rangel T, da Silva S, Damasceno B, Ribeiro B Biomedicines. 2023; 11(2).

PMID: 36831091 PMC: 9952899. DOI: 10.3390/biomedicines11020555.


Parasite infections, neuroinflammation, and potential contributions of gut microbiota.

Alloo J, Leleu I, Grangette C, Pied S Front Immunol. 2022; 13:1024998.

PMID: 36569929 PMC: 9772015. DOI: 10.3389/fimmu.2022.1024998.


Persisting Microbiota and Neuronal Imbalance Following Infection Reliant on the Infection Route.

French T, Steffen J, Glas A, Osbelt L, Strowig T, Schott B Front Immunol. 2022; 13:920658.

PMID: 35898505 PMC: 9311312. DOI: 10.3389/fimmu.2022.920658.


References
1.
Kim J, Kim N, Oh Y, Kim Y, Youn J, Ahn M . CpG oligodeoxynucleotides induce IL-8 expression in CD34+ cells via mitogen-activated protein kinase-dependent and NF-kappaB-independent pathways. Int Immunol. 2005; 17(12):1525-31. DOI: 10.1093/intimm/dxh345. View

2.
Wilson E, Wille-Reece U, Dzierszinski F, Hunter C . A critical role for IL-10 in limiting inflammation during toxoplasmic encephalitis. J Neuroimmunol. 2005; 165(1-2):63-74. DOI: 10.1016/j.jneuroim.2005.04.018. View

3.
OMahony D, Murphy S, Boileau T, Park J, OBrien F, Groeger D . Bifidobacterium animalis AHC7 protects against pathogen-induced NF-κB activation in vivo. BMC Immunol. 2010; 11:63. PMC: 3016395. DOI: 10.1186/1471-2172-11-63. View

4.
Naito Y, Takagi T, Kuroda M, Katada K, Ichikawa H, Kokura S . An orally active matrix metalloproteinase inhibitor, ONO-4817, reduces dextran sulfate sodium-induced colitis in mice. Inflamm Res. 2004; 53(9):462-8. DOI: 10.1007/s00011-004-1281-1. View

5.
Munoz M, Heimesaat M, Danker K, Struck D, Lohmann U, Plickert R . Interleukin (IL)-23 mediates Toxoplasma gondii-induced immunopathology in the gut via matrixmetalloproteinase-2 and IL-22 but independent of IL-17. J Exp Med. 2009; 206(13):3047-59. PMC: 2806449. DOI: 10.1084/jem.20090900. View