The main function of antibody is to combine with antigen (including foreign and self), so as to effectively remove foreign bodies such as microorganisms and parasites invading the body. Antibody is a kind of protein which can specifically bind to antigen. Each antibody binds to a specific antigenic determinant. This combination can inactivate the antigen, or it may be ineffective, but sometimes it will cause pathological damage to the body, such as the production of some autoantibodies such as antinuclear antibody, anti-double stranded DNA antibody and anti-thyroglobulin antibody, which will cause harm to the human body.
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