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The size of information that can be stored in nucleic acids, proteins, and carbohydrates was calculated. The number of hexamers for peptides is 64,000,000 (20(6)) and seems to be impressive in comparison with 4,096 (4(6)) hexanucleotides, but the number of isomers of hexasaccharides is 1.44 × 10(15). Carbohydrates are therefore the best high-density coding system. This language has been named glycocode resp. sugar code. In comparison with peptide dendrimers, the amount of information carried by glycopeptide dendrimers or glycodendrimers is therefore much higher. This is reflected by the variability of structures and functions (activities). This review is about the broad area of peptide and glycopeptide dendrimers. The dendrimeric state and physicochemical properties and general consequences are described, together with a cluster effect. The impact of cluster effect to biological, chemical, and physical properties is discussed. Synthesis of dendrimers by convergent and divergent approaches, "Lego" chemistry, ligation strategies, and click chemistry is given with many examples. Purification and characterization of dendrimers by chromatographic methods, electromigration methods, and mass spectrometry are briefly mentioned. Different types of dendrimers with cyclic core, i.e. RAFTs, TASPs and analogous cyclic structures, carbopeptides, carboproteins, octopus glycosides, inositol-based dendrimers, cyclodextrins, calix[4]arenes, resorcarenes, cavitands, and porphyrins are given. Dendrimers can be used for creation of libraries, catalysts, and solubilizing agents. Biocompatibility and toxicity of dendrimers is discussed, as well as their applications in nanoscience, nanotechnology, drug delivery, and gene delivery. Carbohydrate interactions of glycopeptide dendrimers (bacteria, viruses, and cancer) are described. Examples of dendrimers as anti-prion agents are given. Dendrimers represent a fast developing area which partly overlaps with nanoparticles and nanotechnologies.

Synthetic study on cystinyl peptides using solution and solid phase methodology was carried out with the central hinge region of immunoglobulin IgG1. In the solid phase synthesis of hexadecapeptide 1c, the time necessary for the formation of disulfide bonds between linear precursors was shortened four times by the action of pure oxygen in buffered solution, in comparison with air oxidation. The product was thus obtained devoid of impurities from side reactions. In the preparation of the shortened bis-cystinyl analogs 2k and 3d of the natural hexadecapeptide 1c, both the classical and polyethylene glycol (PEG6000) solution methods were utilized using a disulfide synthon (Boc-Cys-OPfp)2 to obtain peptide chains in a natural parallel alignment. In the PEG6000 strategy, lysine as a linker on both sides of the polymer was attached to enhance the loading capacity. The leucine residue, instead of proline one, was introduced to the carboxy terminus to facilitate a specific enzymatic cleavage of the peptides from PEG6000 by thermolysine.

Sheep fasciolosis is a devastating burden for the livestock industry. We herein report on immunodiagnosis of fasciolosis, and significant protection of sheep against challenge infection with Fasciola gigantica following immunization with a peptide based on the H-Asp(110)-Lys-Ile-Asp-Trp-Arg-Glu-Ser-Gly-Tyr-Val-Thr-Glu-Val(123)-OH (Fas14p) sequence of F. gigantica cathepsin L-cysteine proteinase. This sequence was synthesized in three different forms: as N(alpha) acetylated (Ac-Asp(110)-Lys-Ile-Asp-Trp-Arg-Glu-Ser-Gly-Tyr-Val-Thr-Glu-Val(123)-OH, FasAc14p), bearing at the amino-terminus an N(alpha) acetylated cystein (Ac-Cys-Asp(110)-Lys-Ile-Asp-Trp-Arg-Glu-Ser-Gly-Tyr-Val-Thr-Glu-Val(123)-OH, FasAcCys14p), and conjugated to sequential oligopeptide carrier Ac-[Lys-Aib-Gly](4)-OH (Ac-SOC(4)) through an amide bond formed between Val(123) carboxylic group of the epitope and the lysine N(epsilon) groups of the carrier (Ac-[Lys(Fas14p)-Aib-Gly](4)-OH). Ac-[Lys(Fas14p)-Aib-Gly](4)-OH failed to readily discriminate between naïve and infected sheep. In contrast, the free peptides reproducibly differentiated between parasite-free sheep, sheep infected with parasites other than Fasciola, and experimentally Fasciola-infected sheep. The data together indicated that the peptides might be of considerable use for discriminating between early and late, and low and high burden, sheep infection with F. gigantica. FasAc14p was chosen to determine whether a peptide based on a critical enzymatic site of cathepsin L proteinase may induce protection against challenge infection. Sheep immunization with FasAc14p peptide induced significant expression of interleukin-4 mRNA, and humoral antibodies that bound to molecule(s) on the intact surface membrane of newly excysted juvenile worms, and mediated their attrition. The immune responses were associated with significant (P < 0.02) decrease of 23.1% in worm recovery, but with no decrease in the size or maturation of worms recovered., ((c) 2007 Wiley Periodicals, Inc.)

Dendrimers are branched structures and represent a fast growing field covering many areas of chemistry. Various types of dendrimers differing in composition and structure are mentioned, together with their practical use spanning from catalysis, transport vehicles to synthetic vaccines. The main stress is given to peptide dendrimers, namely, multiple antigenic peptides (MAPs). Their synthesis, physicochemical properties, biological activities, etc. have been described with many examples. MAPs can be used as diagnostics, mimetics, for complexation of different cations, as vaccines against parasites, bacteria, viruses, etc., ((c) 2005 European Peptide Society and John Wiley & Sons, Ltd.)

Four monoepitopic MAPs (MAP A, B, C and E) and one bis-diepitopic MAP B-E derived fromthe primary sequence of Schistosoma mansoni glyceraldehyde 3-phosphate dehydrogenase, previously tested in BALB/c mice, were examined for their immunogenicity and protective capacity in C57BL/6 mice. Despite multimerization into MAPs, MAP Aand MAP C were poorly immunogenic. In contrast toBALB/c mice, MAP E was non-immunogenic in C57BL/6 mice. Peptide B in the form of MAP B orbis-diepitopic MAPB-E elicited immune responses in C57BL/6 mice that were associated with a significant decrease in worm burden. The MAPs were prepared by the stepwise solid-phase peptide synthesis using Boc/Bzl chemistry, successfully purified on the RP-HPLC column and characterized by RP-HPLC, HPCE and MALDI-TOF MS techniques. A general strategy for MAPs purification is discussed here and the purification of MAP Band MAP E is documented in detail.

Six peptides, A, B1, B, C, D and E derived from the primary sequence of Schistosoma mansoni glyceraldehyde 3-phosphate dehydrogenase (SG3PDH) were selected based on lowest homology to human G3PDH and used for immunization of BALB/c mice. Peptides B1 and D induced immunoglobulin (Ig) G1, IgG2a and IgG2b antibodies that reacted with native and denatured SG3PDH, and were associated with significant (P<0.05) increase in fecundity and burden of challenge worms, respectively. Peptides A, B, C and E elicited a modest cellular immune response, IgG2a and/or IgG2b antibodies, and no effect on challenge worm burden. In contrast, tetrameric multiple antigen peptide (MAP) constructs A, B, C or E elicited strong cellular immune responses and production of IgG1 and/or IgG2a and IgG2b antibodies against the homologous MAP and peptide and SG3PDH. The immune responses were associated with significant (P<0.05) decrease in challenge worm burden for MAP B, and significant (P<0.05) reduction in egg count per worm couple for MAP C or E. The data together indicated the nature and effect of immune responses vary for each SG3PDH-derived peptide.

Recent progress in peptide and glycopeptide chemistry make the preparation of peptide and glycopeptide dendrimers of acceptable purity, with designed structural and immunochemical properties reliable. New methodologies using unprotected peptide building blocks have been developed to further increase the possibilities of their design and improve their preparation and separation. The sophisticated design of peptide and glycopeptide dendrimers has led to their use as antigens and immunogens, for serodiagnosis and other biochemical uses including drug delivery. Dendrimers bearing peptide with predetermined secondary structures are useful tools in protein de novo design. This article covers synthesis and applications of multiple antigen peptides (MAPs), multiple antigen glycopeptides (MAGs), multiple antigen peptides based on sequential oligopeptide carriers (MAP-SOCs), glycodendrimers and template-assembled synthetic proteins (TASPs). In part II the preparation of MAPs, and the utility of glycodendrimers and TASPs are discussed.

Rabbits were immunized with a synthetic octadecapeptide corresponding to the sequence ser-91 to leu-108 of the haemagglutinin heavy chain of H3N2 influenza A viruses. They developed antibodies reactive in solid-phase radioimmunoassay (SPRIA) with the peptide and with haemagglutinins of various H3N2 viruses but not of heterotypic H1N1 and H2N2 viruses. The antibodies were also non-reactive in the haemagglutination-inhibition or neutralization test. Influenza H3N2 virus replicated in the lungs of mice immunized with the peptide to the same extent as in the control mice. Of 27 human sera possessing anti-H3N2 activity or seven sera from rabbits immunized with either virions or haemagglutinins of various influenza A viruses, none was reactive with the peptide in SPRIA.