P2X7R mutation disrupts the NLRP3-mediated Th program and predicts poor cardiac allograft outcomes

Area of Science:

• Immunology
• Molecular Biology
• Transplantation Science

Background:

• Purinergic receptor-7 (P2X7R) and NOD-like receptor P3 (NLRP3) signaling pathways are crucial in T-cell differentiation.
• P2X7R regulates Th17 and Th1 generation, while NLRP3 influences Th2 transcription.

Purpose of the Study:

• To investigate the P2X7R/NLRP3 pathway in T cells and its role in cardiac transplantation outcomes.
• To elucidate the impact of a P2X7R intracellular region loss-of-function mutation on T-cell differentiation and allograft outcomes.

Main Methods:

• Analysis of the P2X7R/NLRP3 pathway in T cells from cardiac-transplanted patients with a specific P2X7R mutation.
• In vitro studies involving transient NLRP3 silencing or overexpression in T cells.
• Preclinical models with genetic deletion of P2X7R and in vitro human T-cell assays with IL-17 blockade.

Main Results:

• A P2X7R mutation leads to NLRP3 displacement, excessive Th17 generation, and abrogated Th2 programming.
• Cardiac transplant patients with the mutant allele exhibit abnormal Th17 generation and poor outcomes.
• NLRP3 modulation (silencing or overexpression) normalized T-cell profiles.
• IL-17 blockade reduced Th17 skewing and abrogated severe allograft vasculopathy in preclinical models.

Conclusions:

• The identified P2X7R mutation dysregulates the P2X7R/NLRP3 pathway in T cells, promoting Th17 skewing.
• This pathway disruption contributes to adverse outcomes in cardiac-transplanted patients.
• Targeting this pathway, particularly IL-17, offers potential for personalized therapy in high-risk patients.