Fig. 7.

Dendritic cell Jagged expression correlates with PD-1 expression on T-effector-memory cells. a Purified T cells were stimulated in vitro in a T:DC (3:1) stimulation co-culture with allogeneic bone marrow-derived dendritic cells in the presence of CD3/CD28 beads (1 μg/mL) for four days with or without treatment with clustered DLL1 (1.5 μg/mL) or monovalent soluble JAG1 (20 μg/mL) constructs. Expression of CD62L, CD44, CTLA-4 and PD-1 was assessed on gated populations as indicated by flow cytometry. Dot plots from a representative experiment out of two independent experiments with duplicates are shown. b-c Lung tumor single cell suspensions from 10 patients were evaluated for the expression of NOTCH ligands on tissue-resident CD11b⁺CD11c^high dendritic cells and PD-1 and NOTCH receptors in populations of T cells by flow cytometry. NOTCH ligands in CD11b⁺CD11c^high cells were compared to PD-1 positivity of Tem and Tcm cells (b) or to NOTCH receptor positive T cell subsets by Pearson’s correlation (c.) All p-values were corrected using the Benjamani- Hochberg procedure; n = 8; * p < 0.05. Color code indicates the strength of correlation. d Scheme summarizing available data on the regulation of T cell responses by Notch ligands