Cross-reactivity between streptococcus and human tissue: a model of molecular mimicry and autoimmunity.

Structural homology between mammalian tissues and microbes has been demonstrated for over 50 years. Twenty years ago the term “molecular mimicry” was coined to describe antigenic structures common to host and protozoal parasites (Damian 1964). This term has since been expanded to include other microorganisms, and knowledge of the phenomenon has increased greatly with the application of newer immunochemical and molecular biological techniques. Cross-reacting antibodies to the shared antigens may arise, and a partial list of these and the disease states with which they may be associated is shown in Table 1.