Antigenic mimicry

Fields, B.A., et al. Molecular basis of antigen mimicry by an anti-idiotope. Nature 374 739-742, 1995. 

Bachmaier K, Neu N, de la Maza LM, Pal S, Hessel A, Penninger JM. Chlamydia infections and heart disease linked through antigenic mimicry. Science 1999 283[5406] 1335-1339. 

H. pylori Expression of Lewis (Le) and Blood Group Antigen Mimicry... 

Negrini, R., Savio, A., Poiesi, C., Appelmelk, B.J., Buffoli, F., Paterlini, A., Cesari, P., Graffeo, M., Vaira, D., Franzin, G. Antigenic mimicry between Helicobacter pylori and gastric mucosa in the pathogenesis of body atrophic gastritis. Gastroenterology 111 (1996) 655-665. 

We have extensively investigated the extent of antigenic mimicry achievable with retro-inverso peptides and evaluated their potential in the development of peptide-based vaccines [106,110]. We designed and synthesized using Fmoc//Bu chemistry an end group-modified retro-inverso analogue 38 of the foot-and-mouth disease virus (FMDV) major antigenic site located within residues 141-159 of the viral VPl protein (Fig. 4) [110,135]. 

Guichard, G., Benkirane, N., Zeder-Lutz, G., van Regenmortel, M.H., Briand, J.P., et al. (1994) Antigenic mimicry of natural L-peptides with retro-inverse peptidomimetics. Proc. Natl Acad. Sci. USA 91 9765-9769. 

Antigenic mimicry Self-antigen that is similar to an antigen on a pathogen. 

The mechanism most commonly invoked to explain the association of infection with autoimmune disease is molecular mimicry that is, the concept that antigens (or more properly, epitopes) of the microorganism closely resemble self-antigens.50 The induction of an immune response to the microbial antigen thus results in cross-reactivity with selfantigens and the induction of autoimmunity. Although epitope specific cross-reactivity has been shown in some animal models,48,51 53 molecular mimicry is clearly demonstrated to be the causative mechanism in few, if any, human diseases.3 54,55... 

There is considerable interest in the role of infectious agents in the development of autoimmune diseases. Some of this interest is based on the concept of molecular mimicry as a causal mechanism. Molecular mimicry refers to the possible pathologic role of cross-reactive antibodies or T cells to a self-antigen that is structurally similar to, and thus shares epitopes with, a viral or other infectious agent. For most autoimmune diseases, however, evidence of molecular mimicry leading to disease is not conclusive.1819 Viruses and other infections also have a less-specific immune effect, stimulating toll-like receptors and proinflammatory cytokine secretion, which is another mechanism that has been postulated to influence autoimmune disease risk.20... 

Cunto-Amesty G, Kieber-Emmons T (2000) Exploiting molecular mimicry in targeting carbohydrate antigens. In Cimningham MW, Fujinami RS (eds) Molecular mimicry, microbes, and autoimmunity, chap 13. ASM Press, Washington, DC... 

Polyneuritis is a disorder of the peripheral nerves. It involves damage to the myelin sheath. The condition is due to inflammation of the axonal membrane caused by viral or bacterial attack, i.e. an antoimmnne disease. Guillain-Barre syndrome is one form of polynenritis and is an example of an autoimmune disease caused by immune mimicry in response to a bacterial or viral antigen. It is discnssed in Chapter 17. 

Another means of tolerance is based on molecular mimicry whereby a native protein has a similar epitope to the antigen, so the immune system is tolerant to this in most individuals. The suggestion is that the patients who are susceptible have some variation in this native protein so that tolerance has not been acquired. 

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