Figure 2.

Gr-1⁺CD11b⁺F4/80⁺ cells from RMA-S tumor-bearing mice suppress T-cell proliferation. Sorted Gr-1⁺CD11b⁺F4/80⁺ (A) or Gr-1⁺CD11b⁺F4/80⁻ (B) cells isolated from tumor-bearing mice on day 21 after tumor cell inoculation were cocultured with splenocytes (spl) from naive mice for 72 hours with ConA at the indicated ratios. Proliferation was assessed by ³H-thymidine incorporation assay. Data show mean plus or minus standard deviation (SD) of triplicate cultures. Asterisks indicate statistical significance (P < .01) determined by Student t test. Representative data selected from 3 independent experiments are shown.