Allergic inflammation immediate allergic reaction or as a Type I allergic reaction. The reaction is caused by the release of histamine and mast cell granule proteins by a process called degranulation, as well as the production of leukotrienes, prostaglandins and cytokines, by mast cells following the cross-linking of allergen specific IgE molecules bound to mast cell FcεRI receptors. These mediators affect nerve cells causing itching, smooth muscle cells causing contraction (leading to the airway narrowing seen in allergic asthma), goblet cells causing mucus production, and endothelial cells causing vasodilatation and edema. The late phase of a Type 1 reaction (which develops 8–12
Juniperus ashei and soft, pulpy and berry-like, green at first, maturing purple about 8 months after pollination. They contain 1–2 seeds, which are dispersed when birds eat the cones and pass the seeds in their droppings. The male cones are 3–5 mm long, yellow, turning brown after pollen release in December to February. The pollen causes a severe allergic reaction for some people in the winter, and people who are allergic to Ashe juniper are also often allergic to the related "Juniperus virginiana". Consequently, what begins as an allergy in the winter may extend into spring since the pollination of "J. virginiana"