FIG. 4.

Contributions of NK cells and CD8⁺ cells to the early IFN-γ response induced by A. actinomycetemcomitans-stimulated mDCs. CD56⁻⁻ represents cultures depleted of NK cells, and CD8⁻⁻ represents cultures depleted of CD8 cells. (A) PBL, CD56⁺-depleted PBL, and CD56⁺ cells were held constant at 10⁶ cells per culture with various numbers of autologous mDCs and were stimulated with 10⁶ A. actinomycetemcomitans cells. The supernatant fluids were collected after 24 h, and IFN-γ production was measured by ELISA. The data are representative of three separate experiments of this type, although the response of CD56⁺ in the absence of DCs was not always seen and is probably attributable to a few DCs contaminating this preparation. The data are expressed as means ± SE. (B) PBL, CD56⁺-depleted PBL, CD8⁺-depleted PBL, and both CD56⁺- and CD8⁺-depleted cells were held constant at 10⁶ cells per culture with various numbers of autologous mDCs and were stimulated with 10⁶ A. actinomycetemcomitans cells. The supernatant fluids were collected after 24 h, and IFN-γ production was measured by ELISA. These data are representative of three separate experiments of this type. The data are expressed as means ± SE.