Antigen cocktail

An Antigen Cocktail Does Not Improve Vaccine Efficacy.311... 

In primates, DTH assessment requires a more vigorous and multifaceted approach, due to the high inter-animal and inter-site variability observed, and the use of smaller numbers of animals in toxicity testing. An approach that was successful in our lab included the use of antigen cocktail containing... 

In that case a cocktail of antibodies directed to antigens located at surfaces of different cells is necessary (Poste and Kirsh,... 

Since these vaecines are imable to evoke a natural infection profile with respeet to the release of antigen they must be administered on a number of occasions. Immunity is not complete until the course of immunization is complete and, with the exeeption of toxin-dominated diseases (diphtheria, tetanus) where the immimogen is a toxoid, will never match the performance of live vaccine delivery. Specificity of the immrme resporrse generated in the patient is initially low. This is particularly the case when the vaeeine is composed of a relatively crude cocktail of killed cells where the immime response is direeted only partly towards antigenic components of the cells that are assoeiated with the infeetion process. This increases the possibility of adverse reaetions in the patient. 

Figure 5.2 Comparison of immunohistochemical staining results among variable periods, 6 h to 30 days, of formalin-fixed, paraffin-embedded human breast cancer tissue (A-N), and cell line MCF-7 sections (O-Bl). All four markers, estrogen receptor (ER) (A-G), CK (cytokeratin cocktail, H-N), Her2/neu (O-U), and MIB-1 (V-Bl), showed comparable positive immunostaining results at +++ level after antigen retrieval. Original magnification x 200. Bar = 50 tm. Reproduced with permission from Shi et al., I Histochem. Cytochem. 2007 55 105-109. See color insert.

Figure 7.3 The ER 1D5 peptide only binds to the ER 1D5 mAb (upper left and lower right). Other mAbs do not bind. The antibody abbreviations in the lower panel are Her2 11G5, and 9C2, human epidermal growth factor receptor type 2 clones 11G5 and 9C2 Mela-HMB45, melanocyte-specific antibody clone HMB45 Vimen V9, vimentin clone V9 Anti-LCA, anti-leukocyte common antigen clones PD7/26 and 2B11, combined as a cocktail Mouse poly IgG, mouse polyclonal IgG. Reproduced with permission from Sompuram et al.7...

Indirect methods for immunofluorescent detection of multiple tissue antigens in their simplest form make use of primary antibodies that are raised in different species. Bound primary antibodies can accordingly be visualized with differently labeled species-specific secondary antibodies. Primary antibodies to a pair of different antigens (e.g., rabbit anti-antigen A and mouse anti-antigen B) can be mixed and applied as a cocktail. The same is valid for a mix of secondary antibodies (e.g., goat anti-rabbit-FITC and goat anti-mouse-Cy3) as shown in Fig. 8.1. 

For the most part, each of the antigens described above elicits low to moderate levels of protection. On the assumption that their protective properties might be additive, attempts have been made to improve vaccine efficacy by combining two or more of the antigens in a cocktail. A MAP consisting of epitopes from Sm28GST and TPI was found to stimulate both B and T cell responses in mice but no protection data are available (Ferru... 

Compared with pepsin predigestion, microwave heating markedly enhanced the staining of aberrant p53 antigen with Pab 1801-D07 antibody cocktail in paraffin or frozen sections in adenocarcinoma of the lung (Resnick et al., 1995). 

Presynaptic antigens that work well include a cocktail of anti-neurofilament (for instance the monoclonal antibody 2H3) and anti-SV2 to fully label both the axon and the nerve terminal. 

The requirement of multifunctional peptide complexes is perhaps most obvious for the development of subunit peptide vaccines. Successful immunizations with peptide antigens cannot be achieved without the inclusion of a bystander T-helper cell determinant in the chemical entity (4) or in the immunizing cocktail (5). For outbred animals and humans, multiple peptide epitopes, representing determinants of more than one major histocompatibility complex (MHC) proteins, are used to overcome subunit vaccine unresponsiveness, and this also improves antigen presentation in inbred animals (6). 

It is our belief that the ideal vaccines of the future will be constituted by synthetic peptide antigens, carbohydrates, and lipids. Because of the complexity of human T cells, it is also likely that several T-cell peptide epitopes would be required to create a vaccine that is able to induce a universal protective immune response. As vaccination of infants in developing countries is not a simple task, multivalent vaccines or cocktails of vaccines are highly recommended. 

Assays to measure cell-mediated immunity (e.g., DTH) in macaques have produced inconsistent results. The antigens used in these studies and the concentrations of antigens used have varied between laboratories and the results have been highly variable. Most laboratories have used a cocktail of antigens that includes diphtheria, trichophyton, and Candida albicans in incomplete Freund s adjuvant (Price et al., 2004 and Chapter 3.1.3). 

Incubate the sections overnight (about 16 h, at 4 8 C) in pnmaiy antibody cocktail primary monoclonal antibody raised in mouse against antigen A and primary antiserum raised in rabbit against antigen B, diluted in PBS-TX-B see Notes 38, 44, and 45). 

In our hands the cocktail protocol yields the most consistent results. There may be reasons, however, to try sequential visualization for example, if there is reason to believe that one antigen is present in small amounts and that it may be masked by strong labeling of the other antigens. 

Efforts have been made to develop liquid scintillation cocktails that can be utilized to count low energy gamma emitters in a liquid scintillation counter, but these require careful preparation, have been generally inefficient with volumes greater than 3 cc, require quench correction, and are expensive (3) (4) (5) (6)(7). Since both beta and gamma emitters are commonly employed to label antigens in radioimmunoassay procedures, the ability to utilize both isotopes has obvious economic advantages. 

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