CD34+THY-1+LIN- STEM CELLS FROM MOBILIZED PERIPHERAL BLOOD

Over the last ten years there has been increasing use of mobilized peripheral blood (MPB) progenitor cells as grafts for autologous transplantation. Among the cells comprising these MPB autografts is a subpopulation of CD34+Thy-1+Lineage (Lin)-cells, which is enriched for hematopoietic stem cell (HSC) activity. The percentage of CD34+ cells which express Thy-1 is higher in some samples of MPB than in bone marrow (BM). Using myeloid and erythroid cell depletion prior to high speed cell sorting, it is possible to purify sufficient numbers of CD34+Thy-1 +Lin-HSCs from a MPB leuka-pheresis sample for use as an autograft. CD34+Thy-1+Lin-cells will potentially provide a tumor-depleted autograft for cancer patients. This HSC population is also being studied as a potential target for gene transfer for the treatment of patients with HIV, cancer and a variety of genetic disorders.