Murine models of normal and neoplastic human haematopoiesis.

The ability to transplant human haematopoietic cells into immune deficient mice provides a unique opportunity for studying the organization and regulation of the human stem cell developmental program. One challenge for the future will be to reconstitute mice with functional cells of all lineages. The creation of animal models of many haematopoietic diseases should revolutionize the development and testing of novel therapeutic strategies. Significant progress has been made in establishing models of human neoplastic diseases such as leukaemia and lymphoma. Although the number of patients examined is still small, it appears that there may be a correlation between growth in immune deficient mice and clinical outcome. Future studies should examine the range of diseases that grow in mice and whether in vivo assays have prognostic value clinically. These leukaemia models, in conjunction with high efficiency gene transfer techniques, offer a powerful approach to examine the biological consequences of expressing oncogenes or other key regulatory genes on human leukaemic transformation and progression.