Chemoattraction enrichment of thymus-homing bone marrow cells

It has been reported that a population of cells from mouse bone marrow migrates to supernatant made from the incubation of minced fragments of new-born mouse thymuses and that the migrated population is enriched for immature lymphoid cells. In the present study, we show that this method enriches for thymic-homing cells. Migration-enriched cells were labelled with fluorescein isothiocyanate (FITC) and were injected into the tail veins of lethally irradiated mice. Cell suspensions of the thymuses from these experimental mice had 8.1 +/- 1.8% fluorescing cells compared to control mice given equal numbers of non-migration-enriched FITC labelled cells which had 2.4 +/- 1.7% positive cells.