IgE Effector Mechanisms, in Concert with Mast Cells, Contribute to Acquired Host Defense against Staphylococcusaureus

Immunity. 2020 Oct 13;53(4):793-804.e9. doi: 10.1016/j.immuni.2020.08.002. Epub 2020 Sep 9.


Allergies are considered to represent mal-directed type 2 immune responses against mostly innocuous exogenous compounds. Immunoglobulin E (IgE) antibodies are a characteristic feature of allergies and mediate hypersensitivity against allergens through activation of effector cells, particularly mast cells (MCs). Although the physiological functions of this dangerous branch of immunity have remained enigmatic, recent evidence shows that allergic immune reactions can help to protect against the toxicity of venoms. Because bacteria are a potent alternative source of toxins, we assessed the possible role of allergy-like type 2 immunity in antibacterial host defense. We discovered that the adaptive immune response against Staphylococcus aureus (SA) skin infection substantially improved systemic host defense against secondary SA infections in mice. Moreover, this acquired protection depended on IgE effector mechanisms and MCs. Importantly, our results reveal a previously unknown physiological function of allergic immune responses, IgE antibodies, and MCs in host defense against a pathogenic bacterium.

Keywords: IgE; Staphylococcus aureus; allergy; allergy module; bacteria; basophils; degranulation; host defense; mast cells; type 2 immunity.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptive Immunity / immunology*
  • Allergens / immunology
  • Animals
  • Female
  • Hypersensitivity / immunology
  • Hypersensitivity / microbiology
  • Immunoglobulin E / immunology*
  • Mast Cells / immunology*
  • Mast Cells / microbiology
  • Mice
  • Mice, Inbred C57BL
  • Skin / immunology
  • Skin / microbiology
  • Staphylococcal Infections / immunology*
  • Staphylococcal Infections / microbiology
  • Staphylococcal Skin Infections / immunology*
  • Staphylococcal Skin Infections / microbiology
  • Staphylococcus aureus / immunology*


  • Allergens
  • Immunoglobulin E