Thy-1 (CD90) expression within CD34⁺CD38⁻ HSC compartment in MDS patients.

BM CD34-enriched cells (not MNC) were stained with MoAbs against CD34, CD38, and Thy-1 or irrelevant isotype control Abs. (A) Expression profiles of CD34⁺ cells from healthy subject and MDS case with del(5q). (B) Expression profiles of 3 MDS cases with trisomy 8. Left panels show coexpression of CD34 and CD38, with numbers indicating percentages of CD34⁺CD38⁺ and CD34⁺CD38⁻ cells (of total CD34⁺cells) further investigated for Thy-1 expression in right panels. Dotted and solid lines represent Thy-1 expression on CD34⁺CD38⁺ and CD34⁺CD38⁻ cells, respectively. Horizontal bars in the Thy-1 diagrams indicate gates for negative isotype control Ab, including at least 99% of CD34⁺CD38⁻cells.