FIG. 1.

Vesicular stomatitis virus (VSV) encoding a tumor-associated antigen (TAA) induces antigen-specific T-cell activation. Naïve OT-I (Thy1.2⁺) T cells were adoptively transferred on day 7 after implantation of B16ova tumors into C57BL/6 (Thy1.1⁺) mice (three mice/group). Twenty-four hours later, phosphate-buffered saline (PBS), VSV-GFP, or VSV-ova were injected intratumorally. Three days later, (Ai) spleens and tumor-draining lymph nodes (TDLN) or (Aii) tumors were harvested and analyzed by flow cytometry for (A) Thy1.2⁺ cells or (B) interferon gamma (IFN-γ)–producing Thy1.2⁺ cells after pulsing with or without SIINFEKL peptide in TDLN. (C) 15 min, 24 hr, or 48 hr following intratumoral injection of B16ova tumors with VSV, TDLN were harvested and viral titers determined by plaque assay (three mice/group). (D, E) Seven days following implantation of B16ova tumors in C57BL/6 mice (three mice/group), tumors were injected intratumorally with PBS, VSV-GFP, or VSV-ova. Twenty-four hours later, inguinal TDLN were fractionated using magnetic beads into CD11C⁺ and CD11C⁻ populations, which were subsequently co-cultured with naïve OT-I T cells for 60 hr. (D) T-cell activation was measured by IFN-γ secretion by ELISA. The CD11C⁺ population of D was further fractionated into CD11C⁺CD8α⁺ or CD11C⁺CD8α⁻ populations and co-cultured with naïve OT-I. (E) T-cell activation was measured by IFN-γ secretion by ELISA. *p < 0.05, ***p < 0.001. Color images available online at www.liebertonline.com/hum