What is type I hypersensitvity?
Answer:
occur immediately (sec-min)
release of mediators from degranulating mass cells
Ags inducing contact exposed surfaces
sensitization phase: encounter with particular Ag by particular animals induces local plasma cell -> IgE binds to mas cells for up to 3 mos (animal sensitized during this period) -> on seocondary challenge, mast cell bound IgE binds same inhaled Ag -> degranulates -> histmine immediately released -> affect in 15-30 min