Antibody cross-reactivity

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... 

A 54-year-old woman with type 2 diabetes had poor metabolic control, despite using 60-80 units of shortacting and long-acting human insulins for 10 years (34). Transfer to insulin lispro reduced the daily amount of insulin to 28 units. Insulin specific antibodies fell from 2.7 to 0.3% and cross-reactive antibodies, binding both human insulin and insulin lispro, fell from 44 to 16%. Specific insulin lispro antibodies rose from 0 to 0.3%. HbAic fell from 9.1% to 6.8% and body mass index from 30 to 27, probably because of the reduced dose of insulin. 

Cross-Reactive Antibody. The ability of anti-DNA antibodies to bind to other negatively charged substances represents an attractive variant of the... 

Muller-Loennies, S., Brade, L., Brade, H. Neutralizing and cross-reactive antibodies against enterobacterial lipopolysaccharide. Int J Med Microbiol 297 (2007) 321-340. 

Monoclonal antibodies generated with purified Uri eliminated crossreaction to THP and Iof in urine and plasma, respectively. Antibodies directed at the N-linked glycan allowed measurement of Bik in blood without IqI cross-reactivity. Antibodies directed at the peptide allowed measurement of urinary Bik without THP cross-reactivity. These antibodies do not cross-react with aprotinin. These antibodies allow estimating the Iof family in blood. 

Ang CW, Jacobs BC, Brandenburg AH, Laman JD, van der Meche FGA, Osterhaus ADME, Van Doom PA (2000) Cross-reactive antibodies against GM2 and CMV-infected fibroblasts in Guillain-BaiTe syndrome. Neurology 54 1453—1458. 

Jacobs BC, Hazenberg MP, Van Doom PA, Endtz HPh, van der Meche FGA (1997) Cross-reactive antibodies against gangbosides and Campylobacter jejuni bpopolysaccharides in patients with GnUlain-Barre or Miller Fisher syndrome. J Inf Dis 175 729-733. 

B27, the HLA allele proposed to be involved in alkylosing spondylitis, shares an epitope with an enzyme from Klebsiella pneumoniae, a common intestinal Gram negative bacterium. Molecular mimicry is thought to result in cross-reactive antibody formation, joint inflammation and spinal damage. Along with many of the immunotherapies described for other similar arthritic autoimmune disorders, alkylosing spondylitis is treated with anti-inflammatory medications and a low carbohydrate diet to reduce intestinal K. pneumoniae levels. 

Fig. 8.4. Concepts of shared (I) and cross-reactivity (II). Two antigens (A and B) may have one or more identical epitopes and a subpopulation of antibodies from a polyclonal antiserum will react equally with both antigens (shared reactivity). If monoclonal antibodies against the common epitope were used, it would not be possible to distinguish A and B. In cross-reactivity, antibodies reactive with the homologous antigen are also reactive with different epitopes (generally less fit thus lower affinity).

The third category, 2° antibody, summarizes 2° antibody and label information. This information allows the scientist to check the species of the 2° antibodies so that no cross-reactive antibodies will be used. In addition, the information about the fluorophores lists the excitation and emission wavelengths to show that different nonoverlapping fluorophores will be used. 

The evolutionary relations among subunits of F from several sources were tested by immunological cross-reactivity. Antibodies raised against subunits of Fi were reacted with H -ATPase complex from Chlamydomonas and spinach chloroplasts, from beef adrenal, rat liver and yeast mitochondria and with E. coli membranes. The antigen-antibody reaction was tested employing the electrotransfer technique (Rott, Nelson 1981 Towbin et al. 1979). The antibodies employed were raised against the following subunits of the H -ATPase complex o(,, < and... 

---