Vaccination model

As schistosomes are long-lived and pre-pubertal children show little evidence of acquired immunity, can protection be reliably achieved in a permissive host Experiments in rodents and primates with cercariae attenuated by radiation provide an emphatic yes in answer to this question. Over a 40-year-period, many laboratories have reproducibly obtained a 60-70% reduction in worm burden after a single vaccination of high responder mouse strains. The attenuated vaccine model has been extensively investigated as a paradigm for a human vaccine (reviewed by Coulson, 1997) and the salient features are summarized below. 

Fienberg, M.B., and J.P. Moore. 2002. AIDS vaccine models Challenging challenge viruses. Nat Med 8 207. 

EUis, R.W. and Conley, A.J. (1991). Recombinant-derived vaccines models for future development. In Recombinant DNA Technology and Applications. A.Prokop, R.K. Bajpai, and C.Ho, eds. (New York McGraw-Hill), pp. 191 -231. 

In a mouse vaccination model adapted to study the effect of prebiotics, the animals were vaccinated twice with the Influvac Orthomyxovirus influenza) vaccine (booster vaccination after 21 days). The response to the vaccination was measured at day 30 after the first vaccination. Parameters used to identify the response to vaccination were DTH response (skin response after local subcutaneous vaccine injection as an in vivo measure for Thl-mediated immunity), plasma titers of specific antibodies, ex vivo lymphocyte stimulation, T-cell prohferation, cytokine production, and natural killer cell activity. A specific prebiotic mixture (GOS/lcFOS) significantly stimulated the vaccination response in a dose-dependent manner and increased the DTH response indicating a modulation of the immune system toward a Thl-dominated immune response. This effect only... 

The U.S. standard pertussis vacciae is used to standardize the potency of the whole ceU pertussis vacciae. The number of protective units Hi the vaccine is estimated for each lot from the results of simultaneous intracerebral mouse-protection tests of the vaccine being studied and the U.S. reference standard (14,17). The potency of the aceUular vaccines is estimated by then abUity to produce antibodies to the proteins Hi the vaccine Hi a mouse model. These vaccines also undergo a series of animal safety tests to ensure that the iaactivation and toxoiding steps were carried out correctiy (14,17). 

Several other antigens with good immunocontraceptive potential have been identified and investigated in laboratory animals. In most studies, the rate and duration of the immunocontraceptive effect are less than acceptable. A potential problem in immunological approaches to antifertUity research is the need for a safe, effective adjuvant and suitable animal models for evaluating the efficacy and safety of methods (111). Newer and more effective adjuvants are required for contraceptive vaccines and vaccines in general. 

Liposomes have been widely used as model membranes and their physicochemical properties have therefore been studied extensively. More recently, they have become important tools for the study of membrane-mediated processes (e.g., membrane fusion), catalysis of reactions occurring at interfaces, and energy conversion. Besides, liposomes are currently under investigation as carrier systems for drugs and as antigen-presenting systems to be used as vaccines. 

The hepatitis A vaccine may provide effective immunity for 8 years in adults and children. Additionally, kinetic models have theorized that immunity with the vaccine may be longer than 20 years, but this has not been confirmed in clinical trials.1... 

Different approaches have been used to probe the role of chemokines and their receptors in experimental models of arthritis for instance, peptide antagonists or immunization of the host to promote the generation of endogenous neutralizing Abs via the use of chemokine plasmid DNA vaccination (Table 4 and Ref. 50), injection of neutralizing antibodies (Table 5), or mice that lack specific chemokine or chemokine receptors (Table 6). 

Rocio M., Carrera A., Ashley J. et al. Cocaine vaccines Antibody protection against relapse in a rat model. PNAS. 97 6202, 2000. 

Gardner M), Tettelin H, Carucci DJ et al. Chromosome 2 sequence of the human malaria parasite Plasmodium falciparum. Science 1998 282[5391] 1126 1132. Hoffman SL, Rogers WO, Carucci DJ, Venter JC. From genomics to vaccines malaria as a model system. Nature Med 1998 4[12] 1351—1353. 

Standley SM, Kwon TJ, Murthy N et al (2004) Acid-degradable particles for protein-based vaccines Enhanced survival rate for tumor-challenged mice using ovalbumin model. Bioconjug Chem 15 1281-1288... 

Orr N, Robin G, Cohen D, Arnon R, Lowell GH Immunogenicity and efficacy of oral or intranasal Shigella flexneri 2a and Shigella sonnei proteosome-lipopolysaccharide vaccines in animal models. Infect Immun 1993 61 2390-2395. 

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