Immunogen adjuvant

The increased cooperation between T cell, B cell, and macrophage also depends on the immunogen and the host. For molecules with low immunogenicity, adjuvants favor the induction of immune response at the expense of tolerance. Extensive reviews on adjuvant action have been presented by Jolles and Paraf (1973), WHO report No. 595 (1973) and Borek (1977). 

Jiskoot, W., Teerlink, T., Van Hoof, M. M. M., Bartels, K., Kanhai, V., CrommeUn, D. J. A., and Beuvery, E. C. (1986b). Immunogenic activity of gonococcal protein I in mice with three different lipoidal adjuvants delivered in liposomes and in complexes, Inf. Immun.. 54. 333-338. 

Release profiles of these immunogens ean be improved through their formulation with adjuvants (Chapters 14, 15), and the immunogenieity of certain purified baeterial eomponents such as polysaccharides ean be improved by their conjugation to a carrier. 

The adjuvant effect of lipid A on the immunogenicity of polymeric lipospheres was also tested [14], Incorporation of lipid A in PCL lipospheres had no effect on the IgG ELISA titers. However, in the case of PLA lipospheres, lipid A significantly increased the immune response to R32NS1 malaria antigen, resulting in IgG levels similar to those obtained with PCL lipospheres. The adjuvant effect of lipid A incorporated in PLA lipospheres was observed even after 1600-fold dilution of the rabbit sera [14],... 

The results presented in this chapter demonstrate that enhanced immunogenic efficacy can be achieved by using liposphere-based formulations, indicating the potential usefulness of lipospheres in the formulation of human and veterinary vaccines. The liposphere approach employs the fat-lipid environment to achieve several goals to serve as a carrier to protect the antigen, to serve as a depot, and to provide a surface interphase necessary for adjuvant activity. The ability to provide different surface... 

It is reasonable to presume that the immunogenic and adjuvant activity of lipospheres may be the result of a combination of factors. These factors may include a focused and enhanced delivery of the antigen to an antigen-presenting cell (macrophage) and protection of the antigen from metabolic destruction at other sites in the body that do no participate in the immune response. 

The liposphere delivery system as a fat-based adjuvant formulation may both provide the surface interface necessary for solubilization and proper orientation of the adjuvant-active material, and provide potential carriers for vaccines, which may allow better position for processing and presentation of the incorporated antigens, resulting in enhanced immunogenicity. 

Antiserum Production The immunogen, carboxymethylmorphine-bovine-serum-albumin, is emulsified with equal volume of complete Freund s adjuvant. Initial immunization doses are injected into the New Zealand albino rabbits and later on this followed up with booster injections after a period of 6 weeks. The antiserum titer is determined with each booster dose injection and is duly harvested when the titre value is maximum. This is diluted suitably and employed in the radioimmunoassay. ... 

Adjuvant—An oily substance that will form an emulsion aqueous solutions/suspensions of immunogen to enhance the antibody response. Complete adjuvant also contains Tubercele bacilli. 

Antibody Production A thick emulsion of the immunogen (clonazepam-bovine-serum-albumin-con-jugate) is prepared employing complete Freund s adjuvant and two New Zealand white female rabbits are immunized intradermally at multiple sites with the immunogen emulsion. The animals are then administered... 

Immunization and Antibody Production The immunogen 3-hemisuccinyloxyflurazepam, is emulsified with complete Freund s adjuvant. It is injected intradermally into two female New Zealand albino (white) rabbits. Repeated doses are administered twice at interval of two weeks. Subsequently, booster injections of the thick-immunogen-emulsion-paste are administered after a span of 6-weeks. The antibody is harvested when its titer level is high enough, diluted to the suitable-level and employed in the RIA. 

Immunization and Antibody Production The lypphilized immunogen obtained above is dissolved in normal saline and emulsified with equal volumes of complete Freund s adjuvant into a thick paste. Three New Zealand albino rabbits are immunized with the immunogen-paste through intradermal injections. The process is repeated twice at 2-weeks intervals followed by booster doses at monthly intervals. The antiserum is harvested when the plasma titer value is attained maximum. 

Current efforts in vaccine development have predominantly utilized clade B isolates, which represent the subtype in North America and Western Europe. There is also an increased interest in the development of clade A and C vaccines for the expanding pandemic in Asia and sub-Saharan Africa. A concern in fhe clade-specific vaccine strategy is the potential inability to produce large amounts of vaccine specific for distinct clades. This leaves open the question of specific vs. cross-clade effectiveness. Choice of immunogen(s), adjuvant, dose, and mode of administration are also additional variables that must be addressed in candidate vaccine research. 

Bessler WG, et al. Bacterial lipopeptides constitute efficient novel immunogens and adjuvants in parenteral and oral immunization. Behring Inst Mitt 1997 98 390. 

CTL induction experiments consistently demonstrate that IRIV indeed enhance induction of HLA class I-restricted CTL specific for IMsg-ee and Melan-A/Mart-127-35 epitopes. CTL induction in presence of irradiated or nonirradiated CD4+ cells showed that IRIV CTL adjuvance requires CD4+ T-cell activation. Remarkably, IRIV CTL adjuvance observed in our in vitro studies is solely due to IRIV immunogenicity and independent of peptide delivery and protection capacities, as peptides were not encapsulated in nor attached to IRIV. Further studies are warranted to clarify whether and to what extent delivery, protection, and immunogenic capacities of IRIV synergize in CTL adjuvance. The fact that IRIV adjuvance was observed in relation to the tumor-associated epitope Melan-A/Mart-127-35 encourages further evaluation of IRIV as potential adjuvants in cancer... 

Rabbit Immunization. Six rabbits were sub-cutaneously injected with. 2 mg of the immunogen in Freund s adjuvent on days 0, 12, 26, 40 and 59 of the immunization schedule (see Table I). Complete adjuvent was used for the first three immunizations followed by incomplete adjuvent for the final two immunizations. The rabbits were bled as needed using ear vein puncture. 

In addition to the use of adjuvants per se, modification of the antigen may result in increasing its inherent immunogenicity. Such modifications can include ... 

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