Sex-dependent differences in the IgE response modulated by phytohemagglutinin.

Modulation of the IgE response by PHA treatment in relation to animal sex was analysed. Male and female RF mice were immunized with ovalbumin in aluminum hydroxide gel and PHA was injected 1 or 2 days before immunization. Castrated mice were also immunized and received PHA on day -2. The results show that the IgE response is lower in the male than in the female group. An opposite class specific modulation depending on the timing of the PHA inoculation is observed between males and females. This effect is not observed in castrated mice. IgM and/or IgG production is neither modified by sex nor by the mitogen treatment.