Group-2 innate lymphoid cell-dependent regulation of tissue neutrophil migration by alternatively activated macrophage-secreted Ear11

Mucosal Immunol. 2021 Jan;14(1):26-37. doi: 10.1038/s41385-020-0298-2. Epub 2020 May 26.

Abstract

Type-2 immunity is characterised by interleukin (IL)-4, IL-5 and IL-13, eosinophilia, mucus production, IgE, and alternatively activated macrophages (AAM). However, despite the lack of neutrophil chemoattractants such as CXCL1, neutrophils, a feature of type-1 immunity, are observed in type-2 responses. Consequently, alternative mechanisms must exist to ensure that neutrophils can contribute to type-2 immune reactions without escalation of deleterious inflammation. We now demonstrate that type-2 immune-associated neutrophil infiltration is regulated by the mouse RNase A homologue, eosinophil-associated ribonuclease 11 (Ear11), which is secreted by AAM downstream of IL-25-stimulated ILC2. Transgenic overexpression of Ear11 resulted in tissue neutrophilia, whereas Ear11-deficient mice have fewer resting tissue neutrophils, whilst other type-2 immune responses are not impaired. Notably, administration of recombinant mouse Ear11 increases neutrophil motility and recruitment. Thus, Ear11 helps maintain tissue neutrophils at homoeostasis and during type-2 reactions when chemokine-producing classically activated macrophages are infrequently elicited.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dendritic Cells / immunology
  • Dendritic Cells / metabolism
  • Eosinophils / immunology
  • Eosinophils / metabolism
  • Immunity, Innate*
  • Immunomodulation
  • Immunophenotyping
  • Interleukin-13 / biosynthesis
  • Lung / immunology
  • Lung / metabolism
  • Lung / pathology
  • Lymphocytes / physiology*
  • Macrophage Activation / immunology*
  • Macrophages / physiology*
  • Mice
  • Mice, Transgenic
  • Neutrophil Infiltration / immunology*
  • Neutrophils / physiology*
  • Ribonucleases / biosynthesis*
  • Ribonucleases / genetics

Substances

  • Interleukin-13
  • EAR11 protein, mouse
  • Ribonucleases