Related Experiment Video
Updated: Jul 27, 2025
Isolation Protocol of Mouse Monocyte-derived Dendritic Cells and Their Subsequent In Vitro Activation with Tumor Immune Complexes
Published on: May 31, 2018
CD300f signalling induces inhibitory human monocytes/macrophages
Sarah I M Sutherland1, Xinsheng Ju2, Pablo A Silveira2
1Dendritic Cell Research, ANZAC Research Institute, Sydney, NSW, Australia; Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia; Chris O'Brien Lifehouse, Sydney, NSW, Australia.
Abstract:
The CD300 glycoproteins are a family of related leucocyte surface molecules that regulate the immune response via their paired triggering and inhibitory receptors. Here we studied CD300f, an apoptotic cell receptor, and how it modulates the function of human monocytes and macrophages. We showed that CD300f signalling by crosslinking with anti-CD300f mAb (DCR-2) suppressed monocytes causing upregulation of the inhibitory molecule, CD274 (PD-L1) and their inhibition of T cell proliferation. Furthermore, CD300f signalling drove macrophages preferentially towards M2-type with upregulation of CD274, which was further enhanced by IL-4. CD300f signalling activates the PI3K/Akt pathway in monocytes. Inhibition of PI3K/Akt signalling resulting from CD300f crosslinking leads to downregulation of CD274 expression on monocytes. These findings highlight the potential use of CD300f blockade in cancer immune therapy to target immune suppressive macrophages in the tumour microenvironment, a known resistance mechanism to PD-1/PD-L1 checkpoint inhibitors.
