Only CD40L-DC induces cytotoxic activity from CD8 cells.
DCs were derived from adherent PBMCs obtained from 4 HLA-A2–positive donors. Adherent cells were purified through negative selection with CD2 and CD19 Dynabeads. Resultant monocytes were cultured in GM-CSF and IL-4 for 6 to 8 days. Maturation was induced with LPS, TNF-α, or CD40L. CD8 cells from 4 HLA-A2–negative donors were purified by positive selection with CD8 Dynabeads and cryopreserved until needed. On the day DCs were collected, CD8 cells were thawed and further purified by negative selection with CD4, CD19, CD14, and CD56. CD8 lymphocytes and DCs were cultured for 6 days and were assayed on JY (A2+) and 221 (A2−) 51Cr-labeled target cells. Cytotoxic activity is expressed in LU 30/106input cells. (A) Cytotoxic activity induced by imm-DC, LPS-DC, TNF-DC, or CD40L-DC. (B) Cytotoxic activity induced by imm-DC or CD40L-DC in the presence of IL-12, IL-7, or IL-12 plus IL-7. (Each bar pattern represents data for one combination of DC and CD8.)
