DC-10 display low stimulatory capacity and induce T-cell anergy. (A) Naive CD4⁺ T cells were cultured with allogeneic DC-10 or myDCs, isolated from peripheral blood by FACS sorting according to the expression of CD11c, CD83, and CD14, at the ratio of 10:1. Proliferative responses were evaluated 4 days after culture by [³H]-thymidine incorporation for an additional 16 hours. (B) Naive CD4⁺ T cells were cultured with monocyte-derived allogeneic iDCs, DC-10, and mDCs at the ratio of 10:1. Proliferative responses were evaluated 4 days after culture by [³H]-thymidine incorporation for an additional 16 hours. (C) Naive CD4⁺ T cells were stimulated with peripheral allogeneic DC-10 [T(DC-10)] or myDCs [T(myDC)]. After 14 days of culture, T cells were tested for their ability to proliferate in response to monocytes from the same allogeneic donor. Proliferative responses were evaluated 2 days after culture by [³H]-thymidine incorporation. (D) Naive CD4⁺ T cells were stimulated with allogeneic monocyte-derived iDCs [T(iDC)], DC-10 [T(DC-10)], or mDCs [T(mDC)]. After 14 days of culture, T cells were tested for their ability to proliferate in response to mDCs from the same allogeneic donor. Proliferative responses were evaluated 2 days after culture by [³H]-thymidine incorporation. (E) Naive CD4⁺ T cells were stimulated with allogeneic monocyte-derived iDCs [T(iDC)], DC-10 [T(DC-10)], or mDCs [T(mDC)]. After 14 days of culture, T cells were tested for their ability to proliferate in response to tetanus toxoid and Candida albicans. Proliferative responses were evaluated 4 days after culture by [³H]-thymidine incorporation. Results of 1 representative experiment of 7 (A), 24 (B,D), 6 (C), and 3 (E) independent experiments performed are shown. Numbers represent the percentage of inhibition of proliferation of T cells primed with freshly isolated DC-10 compared with proliferation of T cells stimulated with peripheral myDCs (A), or of T cells primed with monocyte-derived iDCs or DC-10 compared with proliferation of T cells stimulated with monocyte-derived mDC (B). The percentage of anergy of T(DC-10) cells compared with T(myDC) cells (C), and of T(iDC) or T(DC-10) cells compared with T(mDC) cells (D) is also indicated. *P ≤ .005, **P ≤ .005, CD4⁺ T cells primed with DC-10 vs naive CD4⁺ T cells primed with myDCs or iDCs (A-B), and T(DC-10) cells vs T(iDC) or T(myDC) cells (C-D).