T lymphocyte development from fetal hematopoietic stem cells

Abstract

Hematopoietic stem cells (HSCs) are isolated from bone marrow and fetal liver as Thy-1lo Lin- Sca-1+ cells. Both adult and fetal HSCs have similar stem cell activities. However, fetal HSCs differentiate more efficiently than adult HSCs into Vγ3 and Vγ4 cells without N nucleotide insertion in the fetal thymic microenvironment. Thus HSC themselves may lose some of their developmental potential during ontogeny. It is possible that only fetal, but not adult, HSCs can differentiate into the fetal types of hematopoietic cells, including Vγ3, Vγ4 T cells, CD5 B cells, and fetal type erythrocytes. © 1993 Academic Press. All rights reserved.