The role of NLRC4 inflammasome in autoinflammatory diseases

Project Information

INFLA-AID

Grant agreement ID: 798068

DOI

10.3030/798068

Project terminated on 30 September 2020

EC signature date 24 April 2018

Start date 1 October 2018

End date 29 January 2021

Funded under

• EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions

Total cost

€ 172 800,00

EU contribution

€ 172 800,00

Coordinated by

VIB VZW
Belgium

Periodic Reporting for period 1 - INFLA-AID (The role of NLRC4 inflammasome in autoinflammatory diseases)

Reporting period: 2018-10-01 to 2020-09-30

Summary of the context and overall objectives of the project

"Our immune system provides a protective mechanism to control and eliminate elements from pathogenic microbes and toxic substances. Upon bacterial infection, such as the foodborne illness caused by Salmonella, our innate immune system initiates an inflammatory response by activating ""inflammasomes"". These multiprotein platforms process proinflammatory cytokines, which are signalling molecules released into the extracellular matrix to resolve the infection.

Although inflammasome-mediated signalling pathways are highly regulated to avoid unwanted immune responses, a gain-of-function mutation in these pathways can cause hyperactivation of the inflammasome. This leads to overproduction of inflammasome-regulated cytokines and provokes autoinflammatory diseases (AID). Recently, gain-of-function mutations in the NLRC4 inflammasome have been attributed to the manifestation of NLRC4-associated AID (NLRC4-AID). In these patients, the onset of life-threatening systematic inflammation begins already at infancy. What is common amongst NLRC4-AID patients is their limited response to IL-1 inhibitors typically administered for AIDs. The objective of the INFLA-AID project is to identify how a mutation in the NLRC4 protein is causing such devastating AID by characterising some of the cellular and molecular mechanisms underlying the activation of the NLRC4 inflammasome."

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

Upon completion of the INFLA-AID project, we have obtained new insights into NLRC4 inflammasome-mediated signalling pathway:

1. We obtained in vivo endogenous NLRC4 protein expression patterns to locate organs important for NLRC4-mediated inflammation.

2. Using NLRC4 mutant mice generated in the host laboratory, we observed that only certain types of cells showed mutation-mediated hyperactivation of the NLRC4 inflammasome signalling pathway that promoted significantly higher release of an inflammasome-generated cytokine.

Currently, the cell type specific upstream regulatory mechanisms of NLRC4 inflammasome signalling are being investigated in the context of healthy and the NLRC4-AID patients.

The results obtained from the INFLA-AID project have been presented in numerous international conferences for immunologists.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

This study will provide an insight into the mechanisms by which one mutation in the NLRC4 protein can sabotage our immune system and will contribute to a better understanding of inflammasomopathies.

By working closely with clinicians specialised in AIDs, we aim to delay disease onset and mitigate the symptoms in patients with aberrant NLRC4 inflammasome activities.

Furthermore, our findings will be of interest for immunologists as they highlight a unique characteristic of NLRC4 inflammasome that originates from its cell type-specific activation mechanism.

Inflammatory signalling outcomes of healthy or mutated NLRC4 inflammasome