Modulation of DC function by C3 inhibitor (APT070). (A) Inhibition of mouse complement activity by APT070 (hemolytic assay). Values are means plus or minus SEM of triplicate determination for each condition. (B) APT070 bound to cultured BM DCs, which was detected by flow cytometry and immunochemical staining with antihuman CR1-3mAb. Slides were viewed with a Leitz DIAPLAN microscope using a PL Fluotar lens (Leitz, Wetzlar, Germany) with 100×/1.32 NA oil immersion and Permafluor mountant medium (Thermo Electron, Cheshire, United Kingdom). Images were acquired using a Nikon DXM1200 digital camera and processed with LUCIA imaging software version 4.71 (Jencons-PLS, Leighton Buzzard, United Kingdom) and Adobe Photoshop version 6.0 (Adobe Systems, San Jose, USA). (C) IL-12 and IL-10 production in response to LPS stimulation in APT070 or control molecule treated DCs (ELISA). Data are shown as means plus or minus SEM (n = 4). Data were analyzed by Student t test (**P < .005). A representative of 4 independent experiments is shown. (D) Allospecific T-cell responses to the stimulation of APT070 treated or control molecule treated DCs. Irradiated DCs (C57BL/6) and naive alloreactive CD4 T cells (BALB/c) were cocultured in T cell culture medium. Data are means plus or minus SEM (n = 4, for ELISA; or n = 6, for thymidine uptake). Data were analyzed by Student t test (***P < .001). A representative of 4 independent experiments is shown.