CD8?+ Dendritic Cells Dictate Leukemia-Specific CD8+ T Cell Fates.

ABSTRACT: APCs are essential for the orchestration of antitumor T cell responses. Batf3-lineage CD8?+ and CD103+ dendritic cells (DCs), in particular, are required for the spontaneous initiation of CD8+ T cell priming against solid tumors. In contrast, little is known about the APCs that regulate CD8+ T cell responses against hematological malignancies. Using an unbiased approach, we aimed to characterize the APCs responsible for regulating CD8+ T cell responses in a syngeneic murine leukemia model. We show with single-cell resolution that CD8?+ DCs alone acquire and cross-present leukemia Ags in vivo, culminating in the induction of leukemia-specific CD8+ T cell tolerance. Furthermore, we demonstrate that the mere acquisition of leukemia cell cargo is associated with a unique transcriptional program that may be important in regulating tolerogenic CD8?+ DC functions in mice with leukemia. Finally, we show that systemic CD8?+ DC activation with a TLR3 agonist completely prevents their ability to generate leukemia-specific CD8+ T cell tolerance in vivo, resulting instead in the induction of potent antileukemia T cell immunity and prolonged survival of leukemia-bearing mice. Together, our data reveal that Batf3-lineage DCs imprint disparate CD8+ T cell fates in hosts with solid tumors versus systemic leukemia.

SUBMITTER: Kline DE 

PROVIDER: S-EPMC6444187 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature