Antigen structures

Wyatt R, Kwong PD, Desjardins E, Sweet RW, Robinson J, Hendrickson WA, Sodroski JG (1998) The antigenic structure of the HIV gpl20 envelope glycoprotein. Nature 393 705-711... 

It is now well established that the MN blood-group antigens are situated99-101 on the major sialoglycoprotein (glycophorin A) of the erythrocyte membrane. The complex, antigenic structure resides within the first five amino acid residues from the N-terminal portion of the molecule three of these residues are glycosylated. 

Wuhrer, M., Rickhoff, S., Dennis, R.D., Lochnit, G., Soboslay, P.T., Baumeister, S. and Geyer, R. (2000) Phosphocholine-containing, zwitterionic glycosphingo-lipids of adult Onchocerca volvulus as highly conserved antigenic structures of parasitic nematodes. BiochemicalJournal 348, 417-423. 

Xu et al. [5] described the effect of (z>)-penicillamine on the binding of several antiacetylcholine receptor monoclonal antibodies to the Torpedo acetylcholine receptor. Penicillamine is covalently incorporated into the acetylcholine receptor through SS exchange at the cysteine residues of the a-subunit, altering the antigenic structure of the receptor. This effect on the structure of the native receptor at the neuromuscular junction may be responsible for the establishment of the autoimmune response to the acetylcholine receptor in (i))-penicillamine-induced myasthenia gravis. Cysteine and penicillamine interact to form penicillamine-cysteine mixed disulfide complexes [6] ... 

J. Vondrasek, and M. Pisacka, Solid phase synthesis of glycopeptide dendrimers with Tn antigenic structure and their biological activities. Part I, J. Pept. Sci., 5 (1999) 46-55. 

The HpHb and the Hp-globin complexes can also be detected (R4) with rabbit antihemoglobin serum. The combination between Hp and anti-Hp is not influenced even if the neuraminic acid has been split off (L5, L6, P5, S3). That the antigenic structure of dog Hp is related to that of human Hp is evident from the fact that our potent antidog Hp serum cross-reacted with Hp in human sera and that our potent antihuman Hp serum cross-reacted with dog Hp. 

A glycopeptide-BSA conjugate (150) containing the tumor-associated T-antigen structure has been constructed (44,73). 

The discovery of Lp(a) by Berg in 1962 (B6) relied on the production of rabbit antisera against beta-lipoprotein and on the selective absorption of these antisera with individual human sera. When certain human sera were used for absorption, the antisera retained precipitation capacity in radial immunodiffusion with 30-35% of individual human sera, which obviously contained a previous unknown antigen. The particle carrying the new antigen shared antigenic properties with beta-lipoprotein, but had an additional antigenic structure. This was evidenced from the only partial fusion of the precipitin bands formed between a positive human serum, the antibeta lipoprotein antiserum and the new absorbed antiserum. 

Fig. 7. Kinetics of return of native antigenic structure in various limited regions of reduced albumin as determined with restricted populations of antialbumin. Reduced protein was reoxidized in the presence of optimal amounts of rat liver disulfide-exchange enzyme (0.5 mg/ml of RII/2.5 ml of reaction mixture). The reoxidation buffer and other conditions were as described in Section II. (A) 0, Anti-T 5 1M , anti- Tstt-mi anti-N-fragment antialbumin, anti-C-ffagment and anti anti-T,M, j.

LindstrOm J, Peng X, Kuryatov A, Lee E, Anand R, Gerzanich V, Wang F, Wells G, Nelson M (1998) Molecular and antigenic structure of nicotinic acetylcholine receptors. Ann N Y Acad Sci 841 71-86... 

This article focuses mainly on the Immunology of proteins whose complete antigenic structures have been chemically localized and synthetically confirmed. These are Mb, lysozyme, Hb and serum albumin. The antigenic sites of many other proteins are now being Investigated. 

Thus, with this goal In mind, and In order to circumvent the aforementioned problems and render the determination of protein antigenic structures more feasible within a reasonable time, we have devised (5) a novel comprehensive synthetic approach designed to yield the full antigenic profile of the protein under study. This approach consists of the direct synthesis and examination of the immunochemical activities of a series of overlapping peptides having uniform size and overlaps and that encompass the... 

Figure 1. A schematic diagram showing the mode of folding of Mb and Its antigenic structure. The solid black portions represent segments which have been shown to comprise accurately the antigenic sites of the protein. The striped parts, each corresponding to one amino acid residue only, can be part of the antigenic sites with some antisera. The dotted portions represent parts of the molecule which have been shown exhaustively to reside outside antigenic sites (1).

The highlights of the antigenic structure of lysozyme are outlined here. Native lysozyme has three antigenic sites (4). 

In spite of the aforementioned points of resemblance between the antigenic structures of Mb and lysozyme, the antigenic sites of these two proteins are radically different In structural terms (4). The five antigenic sites of Mb are each made up of residues tTTat are directly linked to one another by peptide bonds (U. 

The antibody response to protein antigens has been extensively studied. As briefly outlined, the complete antigenic structures of several proteins have now been determined by chemical methods and confirmed by synthesis (for reviews, see refs. 1,4,35,44). 

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