CD4+CD25+ regulatory T lymphocytes (Tregs) critically contribute to the mechanisms of cancer-induced tolerance. These cells suppress anti-tumoral CD8+ and CD4+ T lymphocytes and can also restrain the function of APCs. We have previously documented the immunostimulatory effects of a chaperone-rich cell lysate (CRCL) anti-cancer vaccine. Tumor-derived CRCL induces tumor immunity in vivo, partly by promoting dendritic cell (DC) and macrophage activation. In the current study, we evaluated the effects of CD4+CD25+forkhead box P3 + Tregs isolated from mice bearing 12B1 bcr-abl+ leukemia on DC and macrophages that had been activated by 12B1-derived CRCL. CRCL-activated DC and macrophages resisted Treg suppression, as the production of proinflammatory cytokines, the activation of transcription factor NF-κB, and their immunostimulatory potential was unaffected by Tregs. Our results thus highlight CRCL as a powerful adjuvant endowed with the capacity to overcome tumor-induced Treg-inhibitory effects on APCs.
- CD4CD25 regulatory T lymphocytes
- Chaperone-rich cell lysate
- Dendritic cells
ASJC Scopus subject areas
- Cell Biology