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What is Regarding IgE which of the following is false. and explain in detail?
Ans. (d) Cross placenta Ref. Ananthanarayan 9/e 99 IgE 8S molecule immunoglobulin with a half life of two days and molecular weight of about 190,000 Structurally resemble IgG Heat labile and affinity for the surface of tisue cells Suceptible to mercaptoethanol. Does not cross the placental barrier or fix complement. Mostly extravascular in distribution. Mainly produced by linings of respiratory and intestinal tracts. IgE is responsible for type I hypersensitivity. Protect against pathogens by mast cell degranulation. Believed to have a special role in defence against helminth infections.