The human/sheep xenograft model: a large animal model of human hematopoiesis.

摘要: Although not 'ideal', xenograft models of human hematopoiesis have proved to be extremely useful experimental systems for the study in vivo engraftment/proliferation potential hematopoietic stem/progenitor cells (HSC). Among these, human/sheep model is unique several respects. This takes advantage fetal immunologic immaturity and developing 'homing' spaces bone marrow obtain donor HSC engraftment normal recipients without conditioning. avoids both possible stromal abnormalities associated with irradiation- and/or chemotherapy-induced immunodeficiency which may limit or long-term maintenance hematopoiesis, use genetically deficient hosts result restricted cell expression. In model, (1) colonizes marrow, (2) persists many years, (3) capable multilineage differentiation, (4) retains its ability respond cytokines, (5) engraft/differentiate secondary recipients. Another aspect sheep large size; this permits repeated evaluation activity same chimeric over long periods. The appears discriminate between different populations exhibits a degree sensitivity that suggests utero approach serve as biologically relevant identification, characterization, from available sources.