Reprogramming
of Neutrophils as Non-canonical Antigen
Presenting Cells by Radiotherapy–Radiodynamic Therapy to Facilitate
Immune-Mediated Tumor Regression
posted on 2021-10-28, 15:03authored byNining Guo, Kaiyuan Ni, Taokun Luo, Guangxu Lan, Ainhoa Arina, Ziwan Xu, Jianming Mao, Ralph R. Weichselbaum, Michael Spiotto, Wenbin Lin
Ineffective antigen cross-presentation
in the tumor microenvironment
compromises the generation of antitumor immune responses. Radiotherapy–radiodynamic
therapy (RT-RDT) with nanoscale metal–organic frameworks (nMOFs)
induces robust adaptive immune responses despite modest activation
of canonical antigen presenting dendritic cells. Here, using transplantable
and autochthonous murine tumor models, we demonstrate that RT-RDT
induces antitumor immune responses via early neutrophil
infiltration and reprogramming. Intravenous or intratumoral injection
of nMOFs recruited peripheral CD11b+Ly6G+CD11c– neutrophils into tumors. The activation of nMOFs by
low-dose X-rays significantly increased the population of CD11b+Ly6G+CD11c+ hybrid neutrophils with
upregulated expression of the co-stimulatory molecules CD80 and CD86
as well as major histocompatibility complex class II molecules. Thus,
nMOF-enabled RT-RDT reshapes a favorable tumor microenvironment for
antitumor immune responses by reprogramming tumor-infiltrating neutrophils
to function as non-canonical antigen presenting cells for effective
cross-presentation of tumor antigens.