1. Anti–TGF-β1 antibody neutralizes APB-mediated immune suppression.
Anti–TGF-β1 antibody neutralizes APB-mediated immune suppression. A, tetramer staining assay. Six days after immunization of mice with DCOVA, or DCOVA plus APB, or DCOVA plus APB and anti–TGF-β1 or control antibody (Ab), the tail blood samples were taken from the immunized mice, stained with PE-H-2Kb/OVA I peptide tetramer and FITC-anti-CD8 antibody, and analyzed by flow cytomery. The value in each panel represents the percentage of tetramer-positive CD8+ T cells versus the total CD8+ T-cell population. The value in parenthesis represents the SD. *, P < 0.05 versus cohorts of APB (Student's t test). B, in vivo cytotoxicity assay. The OVA I and Mut1 peptide–pulsed CFSEhigh and CFSElow target cells were i.v. injected at 1:1 ratio into the above immunized mice 6 d after the above immunizations. Sixteen hours later, the splenocytes of immunized mice were analyzed by flow cytometry. The value in each panel represents the percentage of CFSEhigh versus CFSElow target cells remaining in the spleen. The value in parenthesis represents the SD. *, P < 0.05 versus cohorts of APB (Student's t test). C, animal studies. C57BL/6 mice were s.c. vaccinated with DCOVA, or DCOVA plus APB, or DCOVA plus APB and anti–TGF-β1 or control antibody. Eight days after immunization, the immunized mice were s.c. inoculated with EG7 tumor cells. Animal mortality and tumor growth were monitored daily for up to 60 d. One representative experiment of two is shown.
Yufeng Xie et al. Cancer Res 2009;69:
©2009 by American Association for Cancer Research