2008 – Mite exposure triggers immune reactions beyond allergy

Mite allergic patients, exposed to a bacterial antigen, can, in tandem produce antigen/allergen specific IgG4, an antibody associated with anaphylactic reactions.
This study investigates how some mite allergic adults and children, exposed to H influenzae endotoxins, in tandem can produce antigen or allergen-specific IgG4, an antibody associated with anaphylactic reactions. The study raises questions on the possibility of antigen/allergen interactions and asks if this interaction can encourage the development of asthma and allergy in early life. In adults the reaction may prolong symptoms of asthma or rhinitis following a respiratory infection or a heavy cold. A quote from the study: ‘H influenzae endotoxin can directly trigger the release of inflammatory mediators from basophils and eosinophils, and there is evidence from the release of eosinophil cationic protein that they do this in the lungs. ‘Infants can make IgG4 antibody as shown in food allergy and responses to vaccines and virus infections.’ Once triggered, either by mite allergens or bacterial endotoxins, basophils in the blood and mast cells in the lung can release histamine, elastase and tryptase, some of the many pro-inflammatory markers in respiratory disease.

This study may be important in the research of cot deaths caused by the possibility of modified-anaphylaxis due to production of IgG4. To explore this further please refer to: ‘Sudden Infant Death Syndrome’ (Monograph):Coombs RRA, Parish WE, Walls AF, Cambridge Publications (2000)