GRAFT-VERSUS-HOST REACTIONS AND ABROGATION OF ALLOTYPE SUPPRESSION FOLLOWING HISTOINCOMPATIBLE LYMPHOID CELL TRANSFERS IN RABBITS

Abstract

Noninbred rabbits that were characterized for antigens of the major histocompatibility complex (MHC) by serological (RLA) [rabbit lymphocyte antigen] typing were used as adult donors and newborn recipients of lymphoid cells. The majority of RLA-heterozygous (CE) animals transplanted with homozygous type C cells died before 7 wk of age with clinical and histological signs of graft-vs.-host disease, but a small proportion survived with their lymphoid and erythroid systems completely converted to phenotypes of the donors. Takeover of the host''s hematopoietic system was associated with a transient hyperimmunoglobulinemia, mostly of donor origin, and with a striking and permanent abrogation of allotype suppression on the part of donor lymphocytes. Recipients of RLA-compatible cells become stable B lymphocyte chimeras without detectable T cells or erythrocytes of donor type. In the latter case allotype suppression is neither established in the recipient nor abrogated in the donor''s cells.