Figure 1. The human tonsil contains CD34⁺CD38^dimLin^–, CD34⁺CD38^brightLin^–, and CD34⁺CD1a⁺CD11c^– cells.

(A) Expression of CD34 and lineage markers (CD11c, BDCA-2, CD117, CD161, CD19, CD3, CD1a) on CD34-enriched tonsillar cells (left). Total lymphocytes were gated on Lin^– events and analyzed for their expression of CD34 and CD38 (right). The number above each gate indicates the mean percentage of CD34⁺ cells falling within that gate. (B) Expression of CD1a on CD34-enriched tonsillar cells (left). The number above each gate indicates the mean percentage of CD34⁺ cells falling within that gate. Events were gated on CD34⁺CD1a⁺ cells and analyzed for their coexpression of CD10 and CD11c (right). The number within the top left and bottom right quadrants represents the mean percentage of CD34⁺CD1a⁺ cells that are defined as either CD11c⁺ or CD10⁺, respectively. (C) The percentage of CD34⁺ cells that are defined as CD34⁺CD1a⁺CD11c^– in 4 representative human pediatric tonsils. Plots are gated on total CD34⁺ cells. Numbers in the bottom right quadrant indicate the percentage of CD34⁺ cells that are CD1a⁺CD11c^– in that particular donor. All data are from a representative tonsil of (A) 3, (B) 4, or (C) 24 individual donors.