Heterogeneity and mitochondrial vulnerability configurate the divergent immunoreactivity of human induced microglia-like cells

Clin Immunol. 2023 Oct:255:109756. doi: 10.1016/j.clim.2023.109756. Epub 2023 Sep 9.

Abstract

Microglia play versatile roles in progression of and protection against neuroinflammatory diseases. Little is known, however, about the mechanisms underlying the diverse reactivity of microglia to inflammatory conditions. We investigated how human induced microglia-like (iMG) cells respond to innate immune ligands. Quantitative PCR showed that poly-I:C and lipopolysaccharide (LPS) activated the expression of IL1B and TNF. Immunoreactivity of iMG did not differ between controls (n = 11) and patients with neuroinflammatory diseases (n = 24). Flow cytometry revealed that CD14high cells expressed interleukin (IL) -1β after LPS treatment. Immunoblotting showed that poly-I:C and LPS differentially activated inflammatory pathways but commonly induced mitochondrial instability and the expression of pyruvate kinase isoform M2 (PKM2). Furthermore, a potent stimulator of PKM2 (DASA-58) alleviated IL-1β production after LPS treatment. These data indicate that heterogeneous cell populations and mitochondrial stability underlie the divergent immunoreactivity of human iMG in environments.

Keywords: Divergence; Heterogeneity; Immunoreactivity; Microglia; Mitochondria; and CD14.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Flow Cytometry
  • Gene Expression
  • Humans
  • Lipopolysaccharides / pharmacology
  • Microglia* / metabolism
  • Neuroinflammatory Diseases*

Substances

  • Lipopolysaccharides