Peptide/DNA

Arthritis and Chemokine or Chemokine-Receptor Blockade Using Peptides/DNA... 

Target arthritis Species Peptide/DNA Clinical effect mechanism/comments Ref. 

In the following, some examples will be discussed to highlight the scope and the limitations of ACE for the detection of complex formation between DNA samples and interaction partners such as proteins, peptides, DNA or analogs, and smaller molecules. 

Kwok, K.Y., Adami, R.C., Hester, K.C., Park, Y Thomas, S Rice, K.G. (2000). Strategies for maintaining the particle size of peptide DNA condensates following freeze-drying. Int. J. Pharm., 203, 81-88. 

Collard, W.T., Yang, Y., Kwok, K.Y., Park, Y. and Rice, K.G. (2000b) Biodistribution, metabolism, and in vivo gene expression of low molecular weight glycopeptide polyethylene glycol peptide DNA co-condensates. J. Pharm. Sci., 89, 499-512. 

To avoid high cytotoxicity and molecular heterogeneity of poly(L-lysine), molecularly homogenous lysine-rich synthetic peptides have been used for gene transfer. It is known that the active sites of enzymes, receptor ligands and antibodies usually involve about 5 to 20 amino acids. Thus, it should be possible to design small synthetic peptides to mimic the active sites of viral proteins and formulate synthetic peptide/DNA complexes that are as efficient as vimses, but do not have their limitations. The major components of a peptide-based delivery systems are ... 

Add peptide/DNA solutions at appropriate time points to the washed cells (see Note 5). 

Add ice-cold peptide/DNA solution to one well for the 0 min incubation control... 

Take an aliquot of the peptide/DNA solution and warm to 37°C at each time point (see Note 5). 

Add 150 pL of pie-warmed peptide/DNA solution to each well at the different time points. 

Follow the procedure in Subheading 3.2. However, in step 4 just prior to the addition of the ligand solution, add 100 ig/mL transferrin-AlexaFluor-647 or 300 (rg/mL dextran-Alexa Fluor 647 to the peptide/DNA mixture to visualize clathrin-dependent endocytosis or macropinocytosis, respectively. Analyze the cells either live or fixed and counter-stained. If the cells are fixed and counter-stained, omit adding TO-PRO-3 under step 18, as the fluorescence of TO-PRO-3 is in the far-red spectrum just as Alexa Fluor 647. 

At least 3 wells/construct (no ligand, transferrin and peptide/DNA mixture) is necessary. Non-transfected cells, both with and without ligand should also be included in the experiments. 

The ratio of weight average to number average molecular weight is called the polydispersity, ra. The wider is the molecular weight distribution the higher the polydispersity value. The ra for unimolecular polymer is equal to 1. All natural polymers, such as peptides, DNA, and saccharides, have polydispersity equal to 1. 

Table II. Equilibrium dissociation constants of bZIP peptide DNA complexes...

In summary, the data presented here for peptides binding to different sequences and lengths of DNA demonstrate that afiSnity coelectrophoresis (ACE) (2) can be utilized to study non-spedfic, peptide-DNA binding. It is a simple, gel electrophoresis technique vtdiich measures equilibrium binding of small ligands whose rapid dissodation kinetics may preclude the use of other DNA binding assays. Thus, it is a valuable supplement to other techniques used to measure DNA binding. 

The development of the synthesis of peptides on solid supports has also had a strong impact on other areas of organic synthesis. From the very beginning, some research groups tried, with some success, to export the idea from peptide synthesis to, for instance, the monoalkylation and monoacylation of carboxylic acids,the synthesis of aldehydes and ketones, or to the use of resin-bound dienes or dienophiles to trap reactive intermediates.PI This pioneering work has been fundamental to the much more recent explosion of combinatorial chemistry on solid supports. Synthesis on solid supports has also found application in the synthesis of oligonucleotides, PI oligosaccharides,PI peptide-DNA hybrids,P°l and peptide nucleic acids (PNAs).P l... 

Dickey CA, Morgan DG, Kudchodkar S, Weirrer DB, Bai Y, Cao C, Gordorr MN, Ugerr KE (2001a) Durahorr arrd specificity of humoral immurre resporrses hr mice vaodrrated with the Alzheimer s disease-associated beta-amyloid 1-42 peptide. DNA Cell Biol 20 723—729. 

The object of this chapter is to provide some background for the appreciation of the pharmaceutics of proteins, peptides DNA, oligonucleotides and monoclonal antibodies as therapeutic entities. From an understanding of the nature of amino acids and their physical properties comes an appreciation of the physical nature and properties of peptides, polypeptides and proteins, defined below. The solution properties of proteins in simple and complex media should be understood, together with the factors affecting the stability of proteins in solution. Problems in the formulation of proteins to be overcome will then become clearer. 

Key words Liposomes, Peptides, DNA, Immunostimulatory oligonucleotides, CpG, Immunization,... 

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