Human CD141 dendritic cells (cDC1) are impaired in patients with advanced melanoma but can be targeted to enhance anti-PD-1 in a humanized mouse model.

Background: The conventional type 1 dendritic cell subset (cDC1) is indispensable for tumor immune responses and the efficacy of immune checkpoint inhibitor (ICI) therapies in animal models but little is known about the role of the human CD141 DC cDC1 equivalent in patients with melanoma.

Methods: We developed a flow cytometry assay to quantify and characterize human blood DC subsets in healthy donors and patients with stage 3 and stage 4 metastatic melanoma. To examine whether harnessing CD141 DCs could improve responses to ICIs in human melanoma, we developed a humanized mouse model by engrafting immunodeficient NSG-SGM3 mice with human CD34 hematopoietic stem cells (HSCs) from umbilical cord blood followed by transplantation of a human melanoma cell line and treatment with anti-programmed cell death protein-1 (anti-PD-1).

Caveolae Control Contractile Tension for Epithelia to Eliminate Tumor Cells.

Epithelia are active materials where mechanical tension governs morphogenesis and homeostasis. But how that tension is regulated remains incompletely understood. We now report that caveolae control epithelial tension and show that this is necessary for oncogene-transfected cells to be eliminated by apical extrusion.

The role of dendritic cells in cancer.

Cancer immunotherapy harnesses the ability of the immune system to recognize and eliminate cancer. The potent ability of dendritic cells (DCs) to initiate and regulate adaptive immune responses underpins the successful generation of anti-tumor immune responses. DCs are a heterogeneous leukocyte population comprised of distinct subsets that drive specific types of immune responses.

Differential uptake and cross-presentation of soluble and necrotic cell antigen by human DC subsets.

Cross-presentation is the mechanism by which exogenous Ag is processed for recognition by CD8(+) T cells. Murine CD8α(+) DCs are specialized at cross-presenting soluble and cellular Ag, but in humans this process is poorly characterized. In this study, we examined uptake and cross-presentation of soluble and cellular Ag by human blood CD141(+) DCs, the human equivalent of mouse CD8α(+) DCs, and compared them with human monocyte-derived DCs (MoDCs) and blood CD1c(+) DC subsets.