Iscoms with different quillaja saponin components differ in their immunomodulating activities

In this study we demonstrate that iscoms made with different defined fracti ons of quillaja saponins (fractions A and C) exhibit strikingly different i mmunomodulatory activities. Fraction A has a potent immunomodulatory activi ty by enhancing antigen specific proliferation and production of IL-2 and I FN-gamma, interestingly, this is not reflected by increased levels of IgG2a . The C-fraction on the other hand strongly enhance antibody production and has the ability to modulate the IgG subclass pattern towards IgG2a, in spi te of the fact that C-iscoms induce only low levels of IFN-gamma. Iscoms co ntaining both fractions A and C (Iscoprep(TM)703) induced higher serum anti body responses than iscoms made of either of the fractions alone and showed an enhanced ability to modulate the serum subclass pattern towards IgG2a c ompared to C-iscoms. (C) 1999 Elsevier Science Ltd. All rights reserved.