FIG. 4.

IL-10 produced in the MSC/CaSki cell cocultures diminishes the recognition of CeCa cells by CTLs. CaSki cells were cultured in transwell chambers alone or in the presence of 1 ng/mL of hrIL-10, as well as with BM-, NCx-, or CeCa-MSCs at a ratio of 1:1 (BM, n=5; NCx, n=5; CeCa, n=5), in the absence (A) or presence of neutralizing anti-IL-10 antibody (B). After 96 h, CaSki cells were harvested and challenged against CTLs (CD8⁺ T lymphocytes) specific for peptides TLGIVCPIC and YMLDLQPETT derived from the E7 HPV16⁺ protein, which is expressed in CaSki cells by HLA-A2. CTL cytolytic activity was tested by a standard 4 h [⁵¹Cr] release assay at different ratios 100:1, 50:1, and 25:1 effector:target cells (E:T). The CTL cytolytic activity was also performed on BM-, NCx-, or CeCa-MSCs obtained from the cell cocultures with CaSki either in the absence (C) or presence (D) of neutralizing anti-IL-10. *Indicates significant differences (P<0.05%) in comparison to CaSki cells cultured alone. The data are representative of three independent experiments and shown as mean values±SD.