Flowcytometric assessment of monocyte-derived dendritic cell efficiency for tumor cell lysate uptake in chronic lymphocytic leukemia patients

Dendritic cells (DCs) are the most potent antigen presenting cells in the immune system. They are strongly involved in init iation of primary immune response, autoimmune disease, graft rejection, HIV infection and antitumor response. However, the capability of DCs to activate tumor specific r cells in chronic lymphocytic leukemia (CLL) has been reported, direct demonstration of soluble antigens of tumor lysate uptake had not been shown. In this study we have shown uptake of antigen molecules by immature DCs using Flow cytometric techniques. DCs of two CLL patients and two healthy donors have been evaluated in this study. Peripheral blood monocytes have been purified using mouse anti-CDl4 coated magnetic beads and then' undergone culture process in the presence of rhGM-CSF and rhILA. Generated DCs have been assessed for their ability of uptake FITC-labeled proteins of tumoural B cells lysate by tlow cytometry. Fluorescence intensity in DCs pulsed with FITC-labeled tumor lysat e, after using surface tluorescence quencher (trypan blue), were clearly more than unpulsed controls. This was true for both CLL patients DCs and healthy donors DCs. Immature DCs are capable to uptake soluble protein molecules of tumor lysate prepared from B cells of CLL patients.