Aim
We aimed in this study to use IL-12 to enhance the expansion and cytotoxic functions of ZOL-expanded Vγ9+Vδ2+T cells. Materials and
Background
In a series of our preclinical studies, we have reported that conditioning of α/β CD8+ T cells in vitro with interleukin-12 (IL-12) during their expansion improves their homing phenotype and anti-tumor cytolytic function upon their adoptive transfer in vivo. Vγ9+Vδ2+ T cells can also be expanded in vitro with amino bisphosphonates such as zoledronate (ZOL) for the
Conclusion
The addition of IL12 at the start of the expansion protocol can enhance the activity of γδ T cells which might be mediated in part by the activation of αβ T cells.
Methods
Peripheral blood mononuclear cells (PBMCs) were separated from healthy donors and stage II breast cancer patients. PBMCs (1 × 106 cells/mL) were cultured and treated with ZOL/IL2, ZOL/IL2/IL12, or IL2/IL12. Cultured cells were harvested on days 7 and 14 of culture and their numbers, phenotype, and cytolytic activity were assessed. The levels of pro- and inflammatory cytokines/chemokines in the plasma and supernatants of the cultured cells were analyzed by Luminex.
Results
In healthy subjects, the addition of IL-12 to ZOL/IL2-stimulated PBMCs increased the expansion and the cytotoxic activity of Vγ9+Vδ2+ T cells on days 7 and 14 of culture. The latter was measured by the expression level of the cytolytic molecules granzyme B (GZB) and perforin (PER). Of note, αβ CD8 + T cells were also activated under the same condition but with a lesser extent addition of IL-12 to ZOL/IL2-stimulated PBMCs from cancer patients also induced similar effects but were lower than in control subjects. Interestingly, ZOL/IL2/IL12-treated PBMCs showed higher levels of cytokines/chemokines, in particular, CCL, CCL4, GM-CSF, IL-1rα; IL-12, IL-13, TNF, and IFNγ measured on days 7 and 14.