Immunization peptide, hybridization

The Liskamp group also examined the ability of peptoid-peptide hybrids to be bound by the MHC Class II receptor, an important component of the human immune system [39]. Two of three peptoid substitutions in the 14-residue peptide caused substantial decreases in binding affinity, despite the fact that these were solvent-exposed residues. These results were attributed to a loss of hydrogen-bond contacts as well as to steric clashes caused by unfavorable positioning of the new side chain groups. 

Overall, the current literature about protein biochips has a tendency to make you sad highflying wishes, great plans, and a heap of petty problems that cannot be impressed by wishes. The crux seems to be in the production of aptamers that get at least as close to covering a similar variety of epitopes as antibodies do. Would that succeed with RNA and a number of unusual nucleotides or with RNA-peptide hybrids I have my doubts. Would nature not have already used something similar Are there organisms with aptamer immune systems ... 

Based on the fact that many allergic patients are sensitized to several unrelated allergens, tolerance induction with a panel of simultaneously applied allergens is a desirable goal. We have established a model of polysensitization to major allergens of birch and grass pollen. Intranasal tolerance with a mixture of the immunodominant peptides of the three allergens led to a marked decrease of humoral and cellular Th2-like immune responses [67], Production of hybrid... 

In addition to the three main types of immunological products that are widely available, more specialized preparations include synthetic peptide immune response modifiers such as those used to block T-cell responses in multiple sclerosis labelled monoclonal antibodies for cancer therapy or diagnosis and hybrid toxins containing a bacterial or plant toxin subunit attached to an antibody or human cell receptor-binding protein, and also intended mainly for cancer therapy. These have rather limited applications and for the most part, are designed to suppress or exploit the specificity of immune responses rather than to stimulate them. 

A variation on the yeast two-hybrid technique is the bacterial two-hybrid system. In this case, the target protein and the library-encoded peptide are each fused to a monomer of the DNA binding domain. Only if the target and ligand interact will the DNA binding domain form an active dimeric repressor. An activated repressor results in cells immune to phage infection, allowing for one-step selection of immune cells. This method was shown to be... 

Peptide immunization, vaccination with dendritic cells and hybrid vaccines, adoptive transfer of T cells, and immunization with naked and packaged DNA have been tested in phase I studies only and should only be used in clinical trials (Garbe et al. 2008). 

Danishefsky et al. prepared azido-substimted glycosyl amino acids which where clicked onto alkyne-labeled peptides in solution catalyzed by nanosized copper(O) to afford hybrid molecules 27 that could have potential use as anticancer vaccines (illustrated in Scheme 10.8). An immune response may be ehcited by using appropriate carbohydrate antigens and the authors demonstrated the linking concept with three different antigens. 

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