A myeloid-derived suppressor cell-mediated T-cell suppression assay for functional evaluation of immune cells in tumor-bearing mice.

This protocol describes a procedure to evaluate the ability of Gr-1(+) CD11b(+) myeloid-derived suppressor cells (MDSCs) isolated from the spleen or tumor of a tumor-bearing mouse to suppress antigen-specific T-cell proliferation. MDSCs are cultured with responder splenocytes from an OT-1 T-cell receptor transgenic mouse stimulated with cognate peptide (OVA-257 peptide) or with an irrelevant, control peptide. This protocol spans a 4-d period. The readout is T-cell proliferation by (3)[H]-thymidine incorporation during an 18-h pulse between Days 3 and 4.