Immunotherapy of allergic diseases is associated with problems of adverse s
ystemic reactions. We have shown earlier that liposome entrapped allergen (
LEA) is effective in inducing IgG response and restricting IgE response in
immunized mice. This mode of treatment may be more effective and safer if i
t can prevent anaphylaxis, To determine this feature, mice were administere
d allergen preparations repeatedly and later challenged with the same aller
gen, Mice given liposomal preparation showed lower specific IgE response as
compared to the mice given free allergen or alum adsorbed allergen of Arte
misia scoparia, Specific IgG response was higher in mice immunized with LEA
. The mice immunized with liposomal preparation survived whereas others inj
ected with free allergen or alum adsorbed allergen died probably due to ana
phylaxis, High levels of histamine were observed in mice injected with free
allergen as compared to the mice injected LEA. The increase in plasma hist
amine level may be the cause of anaphylaxis during allergen challenge. In c
onclusion, LEA could be used as a safe and effective mode of immunotherapy
for allergy diseases, since it reduces plasma histamine levels considerably
thereby reducing the chances of anaphylaxis.