IgE production in five inbred rat strains following immunization with alum-precipitated egg albumin

Five inbred rat strains were assessed for their ability to mount IgE responses to alum-precipitated egg albumin (alum EA). Fischer (FI) and Lewis (LE) rats which possess the B1 at the major histocompatibility (Ag-G) locus exhibited weak IgE responses to this antigen. High titer IgE responses were obtained in rats possessing the B3 allele at the Ag-B locus. In some instances the anti-EA IgE response was enhanced following an infection with Nippostrongylus brasiliensis. An effort was also made in these studies to determine whether or not there is some correlation between high IgE production and a depressed capacity for cellular immunity. The basis of these experiments was twofold: (a) recent reports have shown elevated serum levels of IgE in some clinical diseases where cellular immunity is depressed, and (b) in the studies reported here, high titers of IgE were obtained in one rat strain known to be somewhat deficient in its capacity for cellular immunity, whereas very low titers were produced by a strain which is much stronger in this respect. From the results obtained, there appears to be no correlation between IgE production and an inherently weaker capacity for cellular immunity.