Extended Data Fig. 6. Culture of bone marrow cells with GM-CSF + IL-3 induces PD-1 and PD-L1 expression in Lin⁻ and Lin⁺ myelocytes.

a b, Bone marrow cells from WT C57BL/6 mice were cultured with GM-CSF (10 ng/ml) and IL-3 (5 ng/ml) for 24, 48 and 72 hours. Changes in the Lin⁻ and Lin⁺ populations were examined at 48 hours of culture (a). The frequency of the differentiated myeloid cells (CD45⁺CD11b⁺), B cells (B220⁺) and T cells (CD3⁺) was assessed by flow cytometry at the indicated time points (b). c, d, Expression of PD-1 (c) and PD-L1 (d) in Lin⁻ and Lin⁺ subsets examined by flow cytometry at 72 hours of culture. Results are from one of five independent experiments with n = 5 biological replicates per group (**p < 0.01, ***p < 0.005, ****p < 0.001) unpaired t-test two tailed.