All you need to know about the house dust mite
Hardcore Research

Anaphylaxis and the house dust mite (HDM)

Although house dust mite (HDM) allergens are not generally associated with an IgE systemic anaphylaxis reaction, HDM allergic asthma is consider a major risk factor for the condition. Indeed, in most fatalities due to anaphylaxis, asthma is present. A major cause of asthma around the world is exposure to house dust mites.
For asthmatics allergic to HDM, an active and prolonged exposure to the mite's allergens should be identified as a risk factor for severe allergic reaction or anaphylaxis.

Please note the paper referenced below, 'Risk Assessment in Anaphylaxis: current and future approaches', Simons et al. This important paper notes the IgE receptors on antigen-presenting dendritic cells plus the location and potential effect mast cell tryptase release has on the immune response to allergens. In the paper the authors describe two different types of mast cells, each with varying amounts of activation mediator tryptase. One mast cell (MCT) lineage with less tryptase can be found in respiratory epithelium, alveolar wall and small intestinal mucosa, while the second mast cell (MCTC) is located in skin, conjunctivae, heart, perivascular tissue and intestinal submucosa. The location and tryptase 'load' of these differing cells may have important implications in allergic reactions and anaphylaxis.

A recent study found the HDM digestive enzyme allergen Der p1 in the human gastrointestinal tract and called for more research to find the cause and consequence of its presence.


References

'Dust Mites', Introduction: what are dust mites and why are they important? Matthew J. Colloff, 2009, CSIRO Publishing, ISBN 9780643065895

Alpha-tryptase gene variation is associated with levels of circulating IgE and lung function in asthma', Abdelmotelb, AM, Rose-Zerilli MJ, Barton SJ, Holgate ST, Walls AF, Holloway JW, 'Clinical & Experimental Allergy', 2014, 44: (6) 822-830

'Dermatophagoides Farinae': The Digestive System, Arnold R Brody, John C McGrath, G W Wharton, New York Entomology Society. Vol. LXXX, September 1972

Allergens and Allergen Immunotherapy; Fourth Edition, 2008, Chapter 10, Mite Allergens, Enrique Fernandez-Caldas, Leonardo Puerta, Luis Caraballo, Richard F Lockey, Publisher Taylor & Francis. 'Clin. Allergy Immunol'. 2008; 21: 161-182

Nitric oxide production by alveolar macrophanges in response to house dust mite fecal pellets and the mite allergens, Der p1 and Der p2, Peake HL, Currie AJ Steward GA, McWilliam AS, 2008, J Allergy Clinm Immunol, Vol. 112, No 3, 531-537

Pulmonary Dendritic Cells in Local Immunity to Inert and Pathogenic Antigens in the Respiratory Tract, Holt et al, 'The Proceedings of the American Thoracic Society' 2:116-120 (2005)

*Risk Assessment in Anaphylaxis: Current and Future Approaches, 2007, Supp 2, 'Journal Allergy Clin Immunol'. doi: 10.1016j.jaci.2007.05.001 Authors, F Estelle R Simons, Anthony J Frew, Ignacio J Ansotegui, Bruce S Bochner, David B K Golden, Fred D Finkelman, Donald Y M Leung, Jan Lotvall, Gianni Marone, Dean D Metcalfe, Ulrich Muller, Lanny J Rosenwasser, Hugh A Sampson, Lawrence B Schwartz, Marianne van Hage, Andrew F Walls

Presence of commensal house dust mite allergen in : a potential contributor to intestinal barrier dysfunction, Tulic M.K. et al, December 8th, first on-line, 2015. 'Gut', 2016, 65, (5) p757-66