FIG. 4.

Functional consequences of modulating the costimulatory profile of PCa cells via radiation. (A) LNCaP cells were irradiated with 10 Gy (gray bar) or left untreated (0 Gy, open bar). After 72 hours, cells were used as targets in an 18-hour CTL lysis assay. (B) Splenocytes from mice vaccinated with a Listeria-based PSA vaccine were incubated with either untreated TPSA cells (open bar) or TPSA cells irradiated with 10 Gy (gray bar). Graph shows IFN-γ-producing cells/250,000 plated cells as detected by ELISPOT. *Statistical significance relative to untreated cells. CTL, cytotoxic T cells; IFN-γ, interferon-gamma; TPSA, total prostate-specific antigen.