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What is Which of the following immunoglobulin does not fix complement and explain in detail?
Ref Robbins immuno system chapter ... immunoglobulin topic ; see tables for details complement-fixing antibody antibody (primarily IgM and the IgG subclasses 1, 2, and 3) that activates complement when reacted with antigen. ... In humans this antibody, also known as reagin, is of the immunoglobulin class known as IgE.