Figure 9

ASML-exosomes and effector lymphocytes. (A,B) SC, LNC and PEC were stimulated with IL2, LPS or ASML lysate with/without ASML-exosomes: (A) Supernatants were harvested after 4d to evaluate IgM secretion by ELISA. (B) Expression of B cell activation-related signal transduction molecules was evaluated by flow-cytometry after 2d (mean values ± SD, 3 experiments). (C) SC and NKR-P1B⁺ cells were cultured in the presence of 100U IL2/ml or ASML-lysate for 2d. NK cytotoxicity was evaluated with ³H-thymidine labeled AS target cells. (D) NKR-P1B⁺ cells were cultured in the presence of 100U IL2/ml and titrated amounts of ASML-exosomes. Cytotoxicity was evaluated as in (C) after 2d of co-culture. (E) NKR-P1B⁺ cells were cultured in the presence of 100U IL2/ml and 40 μg/ml ASML-exosomes for 2d. Expression of granzymeB, IL2, IFNγ, TNFα, CD25, CD95L, p-Stat5 and CyclinD3 was evaluated by flow cytometry. (F) LNC were cultured in the presence of ASML-lysate for 8d. Where indicated, cultures contained ASML lysate-loaded DC. CTL activity was evaluated with ³H-thymidine labeled ASML and BDX blast target cells: (C,D,F) Mean percent ± SD (triplicates) of cytotoxicity at the indicated E:T ratios. (A-F) Significant differences in cultures containing ASML-exosomes: *. Tumor-exosomes do not hamper a primary B cells response to T cell-dependent or T cell-independent stimuli. But, activation of fyn, syk and PLCγ are slightly impaired. Tumor-exosomes strengthen NK and CTL activity.