What Are Some Mast Cell Disorders?

Discussion Mast cells (MCs) were first discovered by Paul Ehrlich in 1878. Previously in 1869, Nettleship and Tay described a toddler with chronic urticaria and a brown skin lesion which is believed to be the first reported case of mastocytosis. Urticaria pigmentosa was a term first used by Sangster in 1878, and in 1936 the term mastocytosis was used. “Mast cells first evolved 500 million years ago in Ascidians (sea squirts), providing host innate immunity against bacteria and parasites….MCs gained additional functions regulating inflammation, wound healing, coagulation, adaptive immunity and acute allergic responses.” In the bone marrow they differentiate from common myeloid precursors and the immature MCs leave the bone marrow and begin residing in tissues contacting the external environment such as the skin, gastrointestinal and respiratory tracts. They also reside in spaces surround nerves. MCs mature in their terminal location. MC release a variety of inflammatory mediators when activated including storage granules containing histamine, tryptase and other substances, phospholipid membrane metabolism substances and by synthesizing additional substances such as cytokines and chemokines. Mature MCs have two major subpopulations with one type residing in a particular location but there is interconversion between the two depending on the microenvironment. Learning Point As the understanding of mast cells has evolved so has the terminology and classification,...
Source: PediatricEducation.org - Category: Pediatrics Authors: Tags: Uncategorized Source Type: news