The effect on pregnancy of treatment with antibodies against pregnancy-associated murine protein 1 (PAMP-1) in inbred and outbred mice

Intravenous injection of small amounts of monospecific rabbit IgG against pregnancy-associated murine protein 1 (PAMP-1) induced abortion in mice where there was a histocompatibility difference between mother and fetuses. No abortion could be induced in inbred mice by a similar treatment. The maternal serum level was found to be higher in inbred than in outbred mice. The abortive dose of antibodies did not influence the serum levels of PAMP-1. Histological examination of uterine, placental and liver tissue showed only morphological changes in the placental tissue of mice which aborted due to the treatment with anti-PAMP-1 antibodies.