In a previous communication (1) we reported that high doses of estrone increased the resistance of mice against an infection with pneumococcus. The present experiments were designed to study the nature of this increased resistance by investigating the effect of estrone upon the antibody-production in rabbits immunized with type 1 pneumococcus.

The effect of sex-hormones on antibody-formation has been studied by few investigators. Castration did not influence appreciably the antibody-formation according to the reports of Weyrauch (2) and Glusman (3). Pregnancy, on the other hand, definitely increased the content of natural and acquired antibodies as shown by the investigations of Dresel and Keller (4), Loewenthal (5), Aycock and Kramer (6) and Hudson and coworkers (7). This increase in protective antibodies is highest toward the end of the pregnancy, when the estrogenic hormones reach the highest concentration, and may “reflect the increase in natural resistance to infection during this period” (Perla, 8).

This content is only available via PDF.
You do not currently have access to this content.