Exposure of Microglia to Interleukin-4 Represses NF-κB-Dependent Transcription of Toll-Like Receptor-Induced Cytokines

Autor: Ella A. Zuiderwijk-Sick, Céline van der Putten, Raissa Timmerman, Jennifer Veth, Erica M. Pasini, Linda van Straalen, Paul van der Valk, Sandra Amor, Jeffrey J. Bajramovic
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Frontiers in Immunology, Vol 12 (2021)
Druh dokumentu: article
ISSN: 1664-3224
DOI: 10.3389/fimmu.2021.771453
Popis: Interleukin (IL)-4 is a cytokine that affects both adaptive and innate immune responses. In the central nervous system, microglia express IL-4 receptors and it has been described that IL-4-exposed microglia acquire anti-inflammatory properties. We here demonstrate that IL-4 exposure induces changes in the cell surface protein expression profile of primary rhesus macaque microglia and enhances their potential to induce proliferation of T cells with a regulatory signature. Moreover, we show that Toll like receptor (TLR)-induced cytokine production is broadly impaired in IL-4-exposed microglia at the transcriptional level. IL-4 type 2 receptor-mediated signaling is shown to be crucial for the inhibition of microglial innate immune responses. TLR-induced nuclear translocalization of NF-κB appeared intact, and we found no evidence for epigenetic modulation of target genes. By contrast, nuclear extracts from IL-4-exposed microglia contained significantly less NF-κB capable of binding to its DNA consensus site. Further identification of the molecular mechanisms that underlie the inhibition of TLR-induced responses in IL-4-exposed microglia may aid the design of strategies that aim to modulate innate immune responses in the brain, for example in gliomas.
Databáze: Directory of Open Access Journals