Studies of congenitally immunologically mutant New Zealand mice. IX. Age-related microenvironmental effects on autoantibody production in NZB and NZB.X super(id) mice studied by transplantation

The mechanism of polyclonal expansion of B cells and subsequent autoantibody production in New Zealand mice remains a critical question. The authors have been studying the requirements for autoantibody production both in NZB mice as well as NZB mice congenic with the X super(id) gene of CBA/N mice. In this study, an attempt was made to alter the immunologic phenotype of NZB.X super(id) mice by transfer of cells from young and old NZB mice. There was little difficulty in restoring normal levels of serum IgM, IgG3, splenic Lyb-5 cells, and response to DNP-Ficoll in young NZB.X super(id) mice that were injected with young NZB bone marrow cells. Although such animals had an almost immediate change in their immune profile to values characteristic of NZB mice, they required, much like unmanipulated NZB mice, a latency period of an additional 6 mo before autoantibodies were detected. It is suggested that although Lyb-5 cells may be the effective mechanism for autoantibody production, there are other interacting influences that may selectively turn on or turn off autoantibodies and that are required and are responsible for the latency period.