V. Khole et Uc. Hegde, ANTIGENIC-STIMULATION AND BLOCKING OF PREGNANCY IN MICE BY AN ANTIIDIOTYPIC ANTIBODY TO PROGESTERONE, American journal of reproductive immunology [1989], 29(2), 1993, pp. 71-76
PROBLEM: The present study was carried out to see if the anti-idiotypi
c (anti-Id) antibody (Ab2) to progesterone could mimic the immunogenic
ity of the steroid hormone by giving rise to antiprogesterone antibodi
es (Ab3) and whether these antiprogesterone antibodies (Ab3) were biol
ogically active. METHOD: Twenty virgin female Balb/C mice were activel
y immunized with the anti-Id antibody (Ab2). The antiprogesterone anti
body (Ab3) titres in the serum were determined and the animals were us
ed for fertility studies. In the passive immunization studies Balb/C f
emale mice were injected i.p. with 100 mug of anti-Id antibody to see
its effect on pregnancy. RESULTS: The actively immunized animals when
mated showed 80% reduction in their fertility rate. The duration of in
fertility (20-121 days) in these animals could be directly correlated
with the concentration of antiprogesterone antibody (Ab3). The anti-Id
antibody (Ab2) blocked pregnancy in 80% of the passively immunized mi
ce. CONCLUSION: The studies show that anti-Id antibody to progesterone
could mimic the immunogenicity of progesterone and give rise to antip
rogesterone antibodies (Ab3). The anti-Id antibody successfully blocke
d pregnancy in mice both after active and passive immunization.