Stem cell antigens
This project defines and regulates how new antigens transplanted on primitive hematopoietic stem cells (PHSCs) affect repopulation. Such new antigens arise from expression of transplanted genes. Antigenic effects are measured by comparing repopulation in immune competent W-anemic recipients vs. immune deficient irradiated recipients. In cases where we see deleterious effects on repopulating ability due to immune responses, we will test the following ways of inducing tolerance: tissue culture, enrichment of recursors to reduce numbers of antigenically disparate cells, co-injection of lymphoid cells from W-anemic recipients previously made tolerant, and flooding of the system with antigens when cells are injected. We also will test the hypothesis that tissue culture growth reduces antigenicity.