Antibodies that are present in the serum of healthy individuals in the absence of deliberate
immunization with any antigen, are refered to as natural antibodies. A vast majority of natural
antibodies react with one or more self antigens and are termed as natural autoantibodies.
The importance of natural autoantibodies in immune regulation has long been neglected,
since tolerance to self was thought to be primarily dependent on the deletion of autoreactive
clones, rather than on peripheral suppressive mechanisms. Clonal deletion and energy …