Commensal Bacteria Calibrate The Activation Threshold Of Innate Antiviral Immunity

Front 1

What two aspects of immune cells can signals from commensal bacteria influence?

Back 1

Cell development and susceptibility

Front 2

Antibiotic-treated mice (ABX) were subjected to what viruses in this paper?

Back 2

LCMV and influenza virus

Front 3

How were the immune responses of ABX mice after exposure to systemic LCMV or mucosal influenza virus?

Back 3

ABX mice exhibited impaired innate and adaptive antiviral immune responses and substantially delayed viral clearance.

Front 4

Furthermore, what were the other findings from exposure of influenza virus on ABX mice.

Back 4

ABX mice exhibited severe bronchiole epithelial degeneration and increased host mortality after influenza virus infection.

Front 5

What type of cells from ABX mice was transcriptional profiling done on?

Back 5

Macrophages

Front 6

What did transcriptional profiling of macrophages isolated from ABX mice reveal?

Back 6

Macrophages from ABX mice had decreased expression of genes associated with anti-viral immunity.

Front 7

Describe in the general the response of macrophages from ABX mice in response to type I and type II IFNs.

Back 7

Macrophages from ABX mice exhibited defective responses to type I and type II IFNs.

Front 8

Collectively, what was indicated by this study?

Back 8

Commensal-derived signals provide tonic immune stimulation that establishes the activation threshold of the innate immune system required for optimal antiviral immunity.

Front 9

What are two beneficial properties of commensal bacteria?

Back 9

Commensal bacteria can aid in metabolism and compete with pathogens.

Front 10

Alteration of the gut microbiota results in what? (3)

Back 10

Impaired lymphoid tissue development, dysregulated immune cell homeostasis and altered susceptibility to infectious or inflammatory disease.

Front 11

In regards to altered susceptibility to infectious or inflammatory disease, what were the effects of experimental colonisation of Clostridium species and segmented filamentous bacteria (SFB)

Back 11

Clostridium species induced CD4+ regulatory T-cells which made intestinal inflammation better. In contrast, segmented filamentous bacteria, which is associated with increased frequencies of intestinal CD4+ T-helper 17 cells, exacerbates autoimmune inflammation.

Front 12

Are the mechanisms through which commensal-derived signals regulate innate and adaptive immunity to infection defined?

Back 12

They are poorly defined.

Front 13

Briefly describe the specificity of the mammalian innate immune system.

Back 13

the mammalian innate immune system has evolved diverse receptors to detect and respond to detect pathogens.

Front 14

Describe two possible mechanisms by which commensal bacteria could modulate antiviral immunity.

Back 14

1. Crosstalk between the pathways (of the innate immune system) has been reported in which stimulation from one class of pathogens influences the response to another. This could allow commensal-derived signals to regulate anti-viral immunity.
2. Commensal-derived signals could selectively regulate inflammasome-dependent pathways which are associated with the antiviral response.