Anti-tetanus toroid antibody production and protection against lethal doses of tetanus toxin in hu-PBL-SCID mice

Background In this study, severe combined immunodeficiency (SCID) mice, whi ch permit the survival of lymphoid cells of human origin, were used to stud y the human anti-tetanus immune response. Methods: Human peripheral blood l ymphocytes (hu-PBL) obtained from 88 healthy donors (aged from 18 to 62) we re transplanted into SCID mice, and anti-tetanus toroid (Ttd) antibody prod uction and protection against lethal doses of tetanus toxin (Ttx) were inve stigated in the hu-PBL-SCIID mice. Results: The transfer of human PBL evoke d significant human anti-Ttd IgG antibody production for 37.5% of the donor s. After in vivo immunization, the percentage of donors with PBL exhibiting positive anti-TtD IgG production in the mice increased to 54.5%. Mean anti -Ttd IgG levels in the sera were also significantly elevated in response to immunization. The mean IgG titer for the mice injected with PBL from donor s under the age of 40 was significantly higher than that of the mice inject ed with PBL from donors aged 40 or older. Four weeks after the cell transfe r, the mice were challenged with Ttx. The induction of protection against T tx challenge was observed mostly in mice with PBL transferred from donors u nder the age of 40. In vivo immunization in SCID mice with Ttd increased th e number of cases of resistance to Ttx. Conclusions: These results suggest that hu-PBL-SCID mice might serve as a tool for predicting the protective a bility against pathogens in PBL donors and also for evaluating vaccine effi cacy. Copyright (C) 2000 S. Karger AG,Basel.