Flow cytometric assessment of human T-cell differentiation in thymus and bone marrow

作者：Leon W.M.M. Terstappen, Sherry C. Huang, LJ Picker · 发表于：Blood · 年份：1992 · DOI：10.1182/blood.v79.3.666.666 · 被引用次数：190 · 研究领域：T-cell and B-cell Immunology、Immunodeficiency and Autoimmune Disorders、Hematopoietic Stem Cell Transplantation

Abstract Using multidimensional flow cytometry we have defined and quantified the human T-cell differentiation pathway, focusing on those events occurring among the most immature thymocytes and putative bone marrow (BM) T-precursors. Early thymocytes were found to express the CD34 antigen and consisted of a mean 1.2% of cells within human pediatric (n = 9) and 2.0% in fetal thymi (n = 4). All CD34+ thymocytes were atypical blast by morphology, expressed intracytoplasmatic, but not cell surface, CD3, and were cell surface CD2+, CD5+, CD7+, CD38+, CD45+, CD45RA+, CD49d+, and LECAM-1(Leu8)high. CD34high thymocytes lacked surface expression of CD4 and CD8, but as CD34 expression diminished there was a coordinate increase in CD4 levels, followed by the appearance of CD8. The expression of CD1 and CD10 also increased concomitant with the loss of CD34, whereas expression of LECAM-1 diminished with CD34 downregulation. The differential expression of these antigens on early thymocytes (as well as the number of thymocytes displaying these patterns) was highly reproducible among the nine pediatric and four fetal specimens examined, suggesting a precise, stereotyped regulation of early differentiation events. Cell populations with antigen expression patterns suggestive of pluripotent stem cell (CD34high, CD38-), or non-T-lineage committed stem cells (CD34+, CD33+ or CD34+, CD19+) were not identified in either fetal or pediatric thymi (sensitivity = 1/10(4)). The presence of cells with th...