Abstract
Summary
Cholera toxin is known to affect antibody responsiveness, both in vivo and in vitro. In the present study spleen cells from mice pretreated with cholera toxin were markedly deficient in their ability to respond to sheep red blood cells by forming hemolytic antibodies in vitro, whereas splenocytes from mice treated with toxin on the day of immunization or 1 day earlier, showed marked enhancement of antibody responsiveness upon in vitro challenge immunization. Spleen cells from normal mice treated in vitro with cholera toxin at the same time as immunization also showed a marked enhancement of the immune response. Furthermore, normal spleen cell cultures first treated with cholera toxin in vitro and then immunized 2 days later with sheep erythrocytes showed an increased rather than decreased PFC response. These results indicate that depression of antibody formation observed in vivo or in vitro with spleen cells from cholera toxin pretreated animals may reflect an indirect effect, whereas increased responses induced by toxin exposure on the day of immunization, either in vivo or in vitro, may reflect a direct enhancing effect on immunocytes per se.
Get full access to this article
View all access options for this article.