PROTECTION AGAINST HOMOLOGOUS DISEASE IN HYBRID MICE BY PASSIVE AND ACTIVE IMMUNOLOGICAL ENHANCEMENT-FACILITATION

Abstract
Hybrid adult mice can be protected against wasting disease induced by spleen cells from parental origin, by utilizing the immunological enhancement-facilitation phenomenon. Passive enhancement-facilitation was applied using a "B anti-A" type of immune serum injected into (B x A)F1 hybrids before the injection of B lymphoid cells. Active enhancement-facilitation was used in similar strain combinations by means of appropriate immunization of the prospective B spleen cell donors; typically the immunizing material consisted of extracts prepared from lyophilized A tissues (3 mg), and immunizing injections were made 5 days before the donor spleens were transferred. Passive enhancement-facilitation of (B1OD2 x CBA)Fi hybrids receiving B1OD2 spleen cells by means of an anti-CBA B1OD2 immune serum increased survival rates from 1% to 13-40%. This effect of the immune serum was removed by specific absorption. Active enhancement-facilitation displayed its effect clearly in the same strain combination and also in the C57BL6-* (C57BL6 x CBA)F1 combina-tion where specificity of the phenomenon was controlled in a group of hybrids receiving cells from parental donors immunized with extracts of guinea pig lyophilized tissues. Varying immunization procedures or strain combinations sometimes had an opposite effect resulting in an aggravation of the disease (sometimes limited to an increased lymphocytopenia). The spontaneous hemagglutination phenomenon in Gorer-Mikulska''s medium is described as a sign of antibody fixation at the surface of mouse erythrocytes. It results from a graft-versus-host reaction in the present experiments.