Allergy and asthma: distinguishing the causes from the triggers. An eye model for the study of inflammatory events following allergen challenge.

The study of the late-phase reaction to allergen challenge has greatly contributed to increasing understanding of the relationship existing between immunoglobulin E (IgE) triggering, allergic inflammation and bronchial hyperreactivity, as well as to changing our concept from "causes" to "triggers" of asthma. This paper reviews personal studies on a model of conjunctival provocation in allergic subjects. These studies represent the first evidence of a late-phase reaction in the human eye and contribute to a better knowledge of the network of cells and mediators involved in allergic inflammation which are responsible for heightened bronchial reactivity in allergic asthma.