Effects of X irradiation on homocytotropic and agglutinating antibody production in mice

The effect of X irradiation on homocytotropic and agglutinating antibody production was studied in mice exposed to 400 rad either before or after immunization with dinitrophenylated Ascaris plus aluminium hydroxide as adjuvant. The adjuvant effect of irradiation was also determined in animals receiving antigen alone. Irradiation 1 day before immunization with adjuvant enhanced IgE and slightly enhanced IgM-antibody formation, although the onset was delayed, but partially suppressed IgG-antibody formation. When the same treatment followed antigen priming, there was a similar enhancement of IgE production which varied with the time between the two procedures. IgG and IgM production, however, were fairly resistant under the same conditions. Irradiation preceding immunization with soluble antigen had no significant adjuvant effect on IgE-, IgG- or IgM-antibody production. On the contrary, it suppressed production of the latter two classes. The results may indicate that production of IgE and of IgG and IgM antibodies in the mouse is regulated by separate mechanisms. (author)