House Dust Mite Allergen Regulates Constitutive Apoptosis of Normal and Asthmatic Neutrophils via Toll-Like Receptor 4

PLoS One. 2015 May 14;10(5):e0125983. doi: 10.1371/journal.pone.0125983. eCollection 2015.

Abstract

House dust mites (HDMs) induce allergic diseases such as asthma. Neutrophil apoptosis is an important process of innate immunity, and its dysregulation is associated with asthma. In this study, we examined the effects of HDM on constitutive apoptosis of normal and asthmatic neutrophils. Extract of Dermatophagoides pteronissinus (DP) inhibited neutrophil apoptosis, but Dermatophagoides farinae extract had no effect. Anti-apoptotic signaling mediated by DP involves in TLR4, Lyn, PI3K, Akt, ERK, and NF-κB in normal neutrophils. DP delayed cleavage of procaspase 9 and procaspase 3 and the decrease in Mcl-1 expression. Supernatant collected from DP-treated normal neutrophils inhibited the constitutive apoptosis of normal neutrophils, and S100A8 and S100A9 were identified as anti-apoptotic proteins in the supernatant. S100A8 and S100A9 transduced the anti-apoptotic signal via TLR4, Lyn, PI3K, Akt, ERK, and NF-κB. DP also suppressed asthmatic neutrophil apoptosis and induced secretion of S100A8 and S100A9, which delayed the constitutive apoptosis. The anti-apoptotic effects of DP, S100A8 and S100A9 in asthmatic neutrophils are associated with TLR4, Lyn, PI3K, Akt, ERK, and NF-κB. The concentrations of S100A8 and S100A9 were significantly elevated in asthmatic bronchoalveolar lavage fluid (BALF) when compared to normal BALF (p<0.01), but not in serum. S100A8 concentration in BALF was positively correlated with the number of BALF neutrophils and negatively correlated with FEV1(%). These findings improve our understanding of the role of HDM in regulation of neutrophil apoptosis in normal individuals and asthmatics and will enable elucidation of asthma pathogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Allergens / pharmacology*
  • Animals
  • Apoptosis / drug effects
  • Asthma / genetics
  • Asthma / immunology*
  • Asthma / pathology
  • Bronchoalveolar Lavage Fluid / cytology
  • Calgranulin A / genetics
  • Calgranulin A / immunology
  • Calgranulin B / genetics
  • Calgranulin B / immunology
  • Case-Control Studies
  • Cell Extracts / pharmacology*
  • Dermatophagoides farinae / chemistry
  • Dermatophagoides farinae / immunology*
  • Dermatophagoides pteronyssinus / chemistry
  • Dermatophagoides pteronyssinus / immunology*
  • Female
  • Gene Expression Regulation
  • Humans
  • Male
  • Middle Aged
  • Mitogen-Activated Protein Kinase 1 / genetics
  • Mitogen-Activated Protein Kinase 1 / immunology
  • Mitogen-Activated Protein Kinase 3 / genetics
  • Mitogen-Activated Protein Kinase 3 / immunology
  • NF-kappa B / genetics
  • NF-kappa B / immunology
  • Neutrophils / drug effects*
  • Neutrophils / immunology
  • Neutrophils / pathology
  • Phosphatidylinositol 3-Kinases / genetics
  • Phosphatidylinositol 3-Kinases / immunology
  • Primary Cell Culture
  • Proto-Oncogene Proteins c-akt / genetics
  • Proto-Oncogene Proteins c-akt / immunology
  • Signal Transduction
  • Toll-Like Receptor 4 / genetics*
  • Toll-Like Receptor 4 / immunology
  • src-Family Kinases / genetics
  • src-Family Kinases / immunology

Substances

  • Allergens
  • Calgranulin A
  • Calgranulin B
  • Cell Extracts
  • NF-kappa B
  • TLR4 protein, human
  • Toll-Like Receptor 4
  • Phosphatidylinositol 3-Kinases
  • lyn protein-tyrosine kinase
  • src-Family Kinases
  • Proto-Oncogene Proteins c-akt
  • MAPK1 protein, human
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3

Grants and funding

This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education.