Epitope specificity

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... 

Janssens W, Carlier V, Wu B, VanderElst L, Jacquemin MG, Saint-Remy JM CD4+ CD25+ T cells lyse antigen-presenting B cells by Fas-Fas ligand interaction in 38 an epitope-specific manner. J Immunol 2003 171 4604-4612. 

Akdis CA, Akdis M, Blesken T, Wymann D, Alkan SS, Muller U, et al Epitope specific T-cell tolerance to phospholipase A2 in bee venom immunotherapy and recovery by IL-2 and IL-15 in vitro. J Clin Invest 1996 98 1676-1683. 

Possibie iow affinity May be difficuit to produce desired antibody Large population of affinities and epitope specificities... 

Figure 2. Human T cells, transduced with hdm2 81-88 epitope-specific and CD8 x A2Kb Tg mice-derived double-chain (Mu dc TCR 8-18) and non functional single-chain TCRs (Mu b 18 and sc TCR 3), were tested for cytolytic activity in response to (o) non-peptide o...

Hoet, R.M., Pieffers, M., Stassen, M.H., et al. (1999). The importance of the light chain for the epitope specificity of human anti-Ul small nuclear RNA autoantibodies present in systemic lupus erythematosus patients. J. Immunol., 163, 3304—3312. 

Subsequent studies using IFN-y synthetic peptides to map the epitope specificity of monoclonal antibodies to murine IFN-y showed that N-terminal specific monoclonal antibodies neutralize IFN-y antiviral activity [29]. In receptor-... 

Woollard, D.J., Gauci, C.G., Heath, D.D. and Lightowlers, M.W. (1998) Epitope specificities and antibody responses to the EG95 hydatid vaccine. Parasite Immunology 20, 535-540. 

Iwasaki, A., Dela Cruz, C.S., Young, A.R. and Barber, B.H. (1999) Epitope-specific cytotoxic T lymphocyte induction by minigene DNA immunization. Vaccine, 17, 2081-2088. 

Most of the recently developed methods for the detection, characterization, and quantitation of proteins are immunoassays based on the fact that proteins are antigens, compounds that can be recognized by an antibody. It is also true that by combining small molecules (haptens) with a larger carrier molecule such as a protein, these methods can be extended to small molecules of interest since antibodies can be produced that recognize epitopes (specific sites on the antigen recognized by the antibody) that include the hapten. 

Monoclonal antibodies are produced as a result of immortalizing and expanding the individual antibody secreting cells artificially in tissue culture (2). Cells grown in this way all have identical epitope specificity and because they are derived from single clones, their product is known as monoclonal antibody. Cells that secrete monoclonal antibodies are known as hybridomas and are typically derived by fusion of two cell types. B-lymphocytes, which have the capacity to make antibody, are obtained from a donor spleen and are physically fused to a tumor cell line, which is immortal. The resulting hybridom as are immortal and produce antibody into the synthetic medium in which they are growing. 

The present article focuses on the occurrence and characterization of derivatives of 5,7-diamino-3,5,7,9-tetradeoxynon-2-ulosonic acids and presents experimental approaches used to identify them and to elucidate the structures of the bacterial polysaccharides that contain the nonulosonic acids. Recent data on the biosynthesis of these sugars and their role in immune recognition and epitope specificity of bacterial glycopolymers are discussed. 

M3. Matsui, K., Breiteneder-Geleff, S., and Kerjaschki, D., Epitope-specific antibodies to the 43 kD glomerular membrane protein podoplanin cause proteinuria and rapid flattening of podocytes. J. Am. Soc. Nephrol. 9, 2013-2026 (1998). 

We used this library to find receptors for the CaaX-box of the H-RAS protein. Because selecting molecular forceps from libraries for H-RAS binding does not ensure these forceps will recognize the carboxy terminus of H-RAS, however, we decided to take a two-pronged screening approach - in addition to screening the library with the protein, we sought to screen with the isolated carboxy-terminal peptide from H-RAS to select molecular forceps that bind this epitope specifically. 

Burks, A.W., Cockrell, G., Connaughton, C., and Helm, R.M. 1994. Epitope specificity and immunoaffinity purification of the major peanut allergen, Ara hi. 7 Allergy Clin Immunol 93 743-750. 

Langhans B, Schweitzer S, Nischalke HD, Braunschweiger I, Sauerbruch T, Spengler U (2004) Hepatitis C virus-derived lipopeptides differentially induce epitope-specific immune responses in vitro. J Infect Dis 189(2) 248-253 Lazzell V, Waldman RH, Rose C, Khakoo R, Jacknowitz A, Howard S (1984) Immunization against influenza in humans using an oral enteric-coated killed virus-vaccine. J Biol Standard 12(3) 315-321... 

Does Epitope Specificity of Gliadin Antibodies of CD Patients Mirror... 

These features of substrate specificity of tTG are mirrored by epitope specificity of gliadin antibodies of CD patients. The common core of the nona-peptides specifically recognized by antibodies of CD patients is QPEQPFP with the amino acid proline residing in position +2 [127]. However, in accordance with results from studies of substrate specificity of tTG [182], exchange of phenylalanine residue for tyrosine completely abolished binding of IgA of CD patients [127]. 

Studies of epitope specificity of gliadin antibodies and substrate specificity of tTG point to a role of proline and phenylalanine in amino acid positions +2 and +3 in glutamine deamidation. In contrast, investigations of T-cell stimulatory peptides reveal several potent T-cell stimulatory peptides from the N-terminal part of a-type gliadin containing the PELPY motif. In this connection, it was shown that substitution of phenylalanine in the +3 position or other amino acids in the glutenin peptide Git-156 inhibited the T-cell proliferative response [186]. 

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