Immunologic tolerance to ultracentrifuged bovine gamma globulin could not be induced in 6-wk old NZB or B/W mice, but developed readily in C3H, NZW, and C57Bl mice. NZB and B/W mice, as well as Balb/c mice, failed to become tolerant to ultracentrifuged human gamma globulin. The NZB and B/W mice also showed higher antibody titers to a standard antigenic challenge. This immunologic hyperreactivity and lack of experimental tolerance may be related to the lack of self-tolerance, autoimmunity, and lymphomas that develop in these mice at a later age
