Wednesday, January 4, 2012


The basis of adjuvanicity is often the recognition of these signals by receptors on accessory cells.
: Free antigen usually disperses rapidly from the local tissues draining the injection site.
The function of repressory is to this by providing a long-lived reverse of antigen.
Most common type of this type of adjuvants used in are aluminium compounds(phosphate or hydroxide)
Incomplete adjuvant in which the antigen is incorporated in the phase of a stabilized water in paraffin oil emulsion ,usually produces higher and far more sustained antibody levels.
However because of long lastingof oil in tissues and occasional production of sterile this adjuvant is not used in vaccines except for anti cancer vaccines.
ex: ISA 720, ISA 51
: Under the influence of the adjuvants macrophages from which provide sites for with antibody forming cells.
All adjuvants virtually deliver antigen to antigen presenting cells and stimulate then by improving immunogenicity through an increase in antigen.
Ribi adjuvant is commonly used formulation in experimental work in a water –in-oil emulsion incorporating MLA and
Effectson lymphocytes
: In mice alum tends to stimulate helper cells of the Th2 family where as complete adjuvant favours the Th1 subset.
Complete is made from incomplete antigen by adding myco bacterial component.
IL-2 has an adjuvant activity in unresponsive leprosy peatients and a single on dialysis peatients effectively reduced their to hepatitis B surface antigen.
: The need for adjuvants which stimulate mucosal immunity is being met by exploiting the of ecoli heat (LT)
Cholera toxin to largest cells.
LT is immunogenic through oral route non toxic through in glycine (LTR192G) used as mucosal adjuvant.
CPG dinucleotides motifs have been shown to act as effective mucosal adjuvants ,stimulating the immune system by interacting withTLR9 and there by promoting Th1 responses.

It is also quite possible that some of the antibodies with in this mixture of antibodies may be directed towards epotopes that are also found in other antigens.
Such antibodies are said to be cross reactive against the other antigen to which they also bond.
Small organic molecules are typically poor immunojens when rejected on their own ,the immune system appears unable to recognize these structures efficiently .
Not with standing this immunologists have found that such molecules can be made visible to the immune system by cooalant coupling to a carrier protein (such as albumn) which in itself immunogenic .such molecules are celled haptens.
ex:In aminobenzene sulphonate.
Immunization with free hapten produces no antibodies to the hapten.
Immunization with hapten group linke to a protein carrier generates antibodies that react with high affinity to hapten alone or linked to a molecule other than the carrier.
Here hapten-antigen.
Hapten protein complex-immunogen.
Although antibodies can be raped against practically any organic substances . some molecules antibody responses much more readily than others.
Thus rejection of the average antigen into an animal will almost always the production of a mixture of antibodies that are directed against different epotopes with antigens.
For practical and economical reasons prophylate immunization should the minimum no.of and the least amount of antigen.
Non living organism and especially purified products frequently require which by definition is a substance recorporated into or rejected simultaneously with antigen which the immune response.
Bacterial structures provide the major source of immune because they provide danger signals of .

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