Epitopes

Rotavirus. Rotavims causes infant diarrhea, a disease which has major socio-economic impact. In developing countries it is the major cause of death in infants worldwide, causing up to 870,000 deaths per year. In the United States, diarrhea is stiU a primary cause of physician visits and hospitalization, although the mortaUty rate is relatively low. Studies have estimated a substantial cost benefit for a vaccination program in the United States (67—69). Two membrane proteins (VP4 and VP7) of the vims have been identified as protective epitopes and most vaccine development programs are based on these two proteins as antigens. Both Hve attenuated vaccines and subunit vaccines are being developed (68). 

Development of a peptide vaccine is derived from the identification of the immunodominant epitope of an antigen (141). A polypeptide based on the amino acid sequence of the epitope can then be synthesized. Preparation of a peptide vaccine has the advantage of allowing for large-scale production of a vaccine at relatively low cost. It also allows for selecting the appropriate T- or B-ceU epitopes to be included in the vaccine, which may be advantageous in some cases. Several vaccines based on peptide approaches, such as SPf66 (95) for malaria and an HIV-1 peptide (142) have been in clinical trials. No peptide vaccines are Hcensed as yet. 

A. Saul and H. Geysen, iu G. Woodrow and M. Leviue, eds.. Identification of Epitopes through Peptide Technology in New Generation Vaccines, Marcel Dekker, New York, 1990. 

A Sail, R Matsumoto, HP McNeil, M Karplus, RL Stevens. Three-dimensional models of four mouse mast cell chymases. Identification of proteoglycan-bmdmg regions and protease-specific antigenic epitopes. I Biol Chem 268 9023-9034, 1933. 

Fremont, D.H., Monnaie, D., Nelson, C.A., Hendrickson, W.A., Unanue, E.R. Crystal structure of I-A in complex with a dominant epitope of lysozyme. Immunity 8 305-317, 1998. 

These predictive methods are very useful in many contexts for example, in the design of novel polypeptides for the identification of possible antigenic epitopes, in the analysis of common motifs in sequences that direct proteins into specific organelles (for instance, mitochondria), and to provide starting models for tertiary structure predictions. 

Antibodies are highly specific, binding only to a restricted part of a given antigen known as an epitope. Given the billions of antibody specificities that may be produced by the immune system, an antibody that recognizes an epitope on virtually any molecule may be produced. It is this property that makes antibodies immensely powerful tools for experimental, diagnostic and therapeutic procedures. 

Fig. 6 Proposed structure of the antigenic epitopes in the ramified region of bupleuran 211c for anti-bupleuran 211c/PG-l-lgG as proposed by Sakurai et al. [49]...

Figure 6 from Carbohydrate Research, vol 311, Sakurai MH, Kiyohara H, Matsumoto T, TsumurayaY, Hashimoto Y, Yamada H (1998) Characterization of antigenic epitopes in anti-ulcer pectic polysaccharides from Bupleurum falcatum L. using several carbohy-drases. p 219-p229, all with permission from Elsevier... 

Artificial glycopolymers having a-galactosyl epitope are of interest from the viewpoint of medical transplantation of pig liver since they can block im-... 

Munk, M.E., Schoel, B., Modrow, S., Karr, R.W., Young, R.A., Kaufmann, S.H. (1989). T lymphocytes from healthy individuals with specificity to self-epitopes shared by the mycobacterial and human 65 kD heat shock protein. J. Immunol. 143, 2844-2849. 

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