Figure 6. IL-7Rα^low EM CD8⁺ T cells have increased migration capacity in response to fractalkine.

(A) Flow cytometric analysis of CX3CR1 expression on IL-7Rα^low, ^high EM and naïve human CD8⁺ T cells. Representative data from more than 10 independent experiments. (B) PBMCs at 1 × 10⁶ cells purified from the peripheral blood of healthy adult donors were seeded into the upper chambers of a transwell migration culture unit. Tissue culture media containing with or without fractalkine (100 ng/ml) was added to the lower chambers. After 4 hours of incubation, cells in the lower chambers were collected and labeled with antibodies to CD3, CD8, CD45RA, CCR7 and IL-7Rα. Labeled cells were analyzed using flow cytometry to analyze IL-7Rα^low, ^high EM and naïve CD8⁺ T cells. Numbers on the Y-axis indicate the difference of cell numbers (delta cell numbers) between the lower chambers containing with and without fractalkine. Bars and error bars indicate the mean and SEM, respectively (n = 8).