Contribution of Leptosphaeria species ascospores to autumn asthma in areas of oilseed rape production

Ann Allergy Asthma Immunol. 2016 Nov;117(5):495-501.e1. doi: 10.1016/j.anai.2016.08.027. Epub 2016 Oct 24.

Abstract

Background: An increase in the number of hospital admissions from September to November in the northern hemisphere has been frequently reported. At this time, some species of fungal genus Leptosphaeria produce numerous ascospores, which are easily airborne. However, we lack knowledge about whether Leptosphaeria produces allergenic proteins.

Objective: To evaluate the potential of Leptosphaeria ascospores to contribute to autumn asthma.

Methods: Detailed bioinformatic analysis of proteins produced by Leptosphaeria maculans available in databases was performed and the data compared with allergens found in other airborne fungi. The concentrations of Leptosphaeria ascospores detected at 2 sites were compared to these obtained in other environments worldwide.

Results: We found that Leptosphaeria species produce proteins with a high identity to commonly known aeroallergens of several well-characterized molds. The level of amino acid identity significantly exceeded the allergen identity thresholds recommended by the Food and Agricultural Organization/World Health Organization (35%), which indicates allergenic properties of L maculans and ensures the same properties in the other Leptosphaeria species.

Conclusion: High concentrations of Leptosphaeria species ascospores in the autumn and postulated allergenicity of their proteins strongly suggest that this genus contributes to worldwide reported autumn asthma. The finding opens the question of allergenicity of the other never studied fungal species present in aeroplankton.

MeSH terms

  • Air Pollutants / analysis
  • Allergens / analysis*
  • Allergens / chemistry
  • Amino Acid Sequence
  • Ascomycota*
  • Asthma
  • Brassica rapa
  • Environmental Monitoring
  • Fungal Proteins / analysis*
  • Fungal Proteins / chemistry
  • Poland
  • Seasons
  • Sequence Alignment
  • Spores, Fungal / isolation & purification*
  • United Kingdom

Substances

  • Air Pollutants
  • Allergens
  • Fungal Proteins