PPARβ/δ-orchestrated metabolic reprogramming supports the formation and maintenance of memory CD8+ T cells 2024 Bevilacqua et al

Abstract

The formation of memory T cells is a fundamental feature of adaptative immunity, allowing the establishment of long-term protection against pathogens. Although emerging evidence suggests that metabolic reprogramming is crucial for memory T cell differentiation and survival, the underlying mechanisms that drive metabolic rewiring in memory T cells remain unclear.

Here, we found that up-regulation of the nuclear receptor peroxisome proliferator–activated receptor β/δ (PPARβ/δ) instructs the metabolic reprogramming that occurs during the establishment of central memory CD8+ T cells. PPARβ/δ-regulated changes included suppression of aerobic glycolysis and enhancement of oxidative metabolism and fatty acid oxidation. Mechanistically, exposure to interleukin-15 and expression of T cell factor 1 facilitated activation of the PPARβ/δ pathway, counteracting apoptosis induced by antigen clearance and metabolic stress. Together, our findings indicate that PPARβ/δ is a master metabolic regulator orchestrating a metabolic switch that may be favorable for T cell longevity.

Editor’s summary

After initial antigen encounter, some T cells persist and differentiate into long-lived memory cells. This process is accompanied by metabolic reprogramming that supports survival and memory functions, but the key factors driving memory T cell metabolic adaptation remain unclear.

Using mouse models of viral infection and melanoma, Bevilacqua et al. found that the nuclear receptor peroxisome proliferator–activated receptor β/δ (PPARβ/δ) supports the switch from aerobic glycolysis to oxidative metabolism during central memory CD8+ T cell formation. PPARβ/δ expression was required for memory T cell responses upon rechallenge, as well as the generation of TCF-1+ progenitor exhausted T cells during chronic antigen exposure. Together, these findings identify PPARβ/δ as a key regulator of metabolic reprogramming during memory T cell differentiation.

Paywall, https://www.science.org/doi/10.1126/sciimmunol.adn2717