Cytokine-armed dendritic cell progenitors for antigen-agnostic cancer immunotherapy.

Dendritic cells (DCs) are antigen-presenting myeloid cells that regulate T cell activation, trafficking and function. Monocyte-derived DCs pulsed with tumor antigens have been tested extensively for therapeutic vaccination in cancer, with mixed clinical results. Here, we present a cell-therapy platform based on mouse or human DC progenitors (DCPs) engineered to produce two immunostimulatory cytokines, IL-12 and FLT3L.

Dendritic cell cross-dressing and tumor immunity.

In addition to direct and cross-presentation, dendritic cells (DCs) can present tumor antigens (TAs) to T cells via a hitherto poorly understood mechanism called "cross-dressing." DC cross-dressing involves the acquisition of preformed peptide-major histocompatibility class I/II (p-MHC) complexes from cancer cells. This process has been documented both in cell culture and in tumor models; may occur via the uptake of tumor-derived extracellular vesicles or the horizontal transfer of plasma membrane fragments from cancer cells to DCs; and can be enhanced through DC engineering for therapeutic applications.

Overcoming microenvironmental resistance to PD-1 blockade in genetically engineered lung cancer models.

Immune checkpoint blockade (ICB) with PD-1 or PD-L1 antibodies has been approved for the treatment of non-small cell lung cancer (NSCLC). However, only a minority of patients respond, and sustained remissions are rare. Both chemotherapy and antiangiogenic drugs may improve the efficacy of ICB in mouse tumor models and patients with cancer.