Global alteration of T-lymphocyte metabolism by PD-L1 checkpoint involves a block of de novo nucleoside phosphate synthesis

Nicolaos Jay Palaskas; Jacob David Garcia; Roksana Shirazi; Daniel Sanghoon Shin; Cristina Puig-Saus; Daniel Braas; Antoni Ribas; Thomas Glen Graeber

doi:10.1038/s41421-019-0130-x

Global alteration of T-lymphocyte metabolism by PD-L1 checkpoint involves a block of de novo nucleoside phosphate synthesis

Cell Discov. 2019 Nov 26:5:62. doi: 10.1038/s41421-019-0130-x. eCollection 2019.

Authors

Nicolaos Jay Palaskas^{1

2}, Jacob David Garcia³, Roksana Shirazi⁴, Daniel Sanghoon Shin^{1

2}, Cristina Puig-Saus¹, Daniel Braas^{2

5

6}, Antoni Ribas^{1

2

7

8

9}, Thomas Glen Graeber^{2

5

6

7

8}

Affiliations

¹ 1Division of Hematology and Oncology, Department of Medicine, University of California Los Angeles, Los Angeles, CA 90095 USA.
² 2Department of Molecular, Cellular, and Integrative Physiology, University of California Los Angeles, Los Angeles, CA 90095 USA.
³ 3Department of Molecular, Cellular, and Developmental Biology, University of California Los Angeles, Los Angeles, CA 90095 USA.
⁴ 4Department of Microbiology, Immunology, and Molecular Genetics, University of California Los Angeles, Los Angeles, CA 90095 USA.
⁵ 5Crump Institute for Molecular Imaging, University of California Los Angeles, Los Angeles, CA 90095 USA.
⁶ 6Metabolomics Center, University of California Los Angeles, Los Angeles, CA 90095 USA.
⁷ 7Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, CA 90095 USA.
⁸ 8Jonsson Comprehensive Cancer Center, University of California Los Angeles, Los Angeles, CA 90095 USA.
⁹ 9Division of Surgical Oncology, Department of Surgery, University of California Los Angeles, Los Angeles, CA 90095 USA.

Abstract

Metabolic obstacles of the tumor microenvironment remain a challenge to T-cell-mediated cancer immunotherapies. To better understand the interplay of immune checkpoint signaling and immune metabolism, this study developed and used an optimized metabolite extraction protocol for non-adherent primary human T-cells, to broadly profile in vitro metabolic changes effected by PD-1 signaling by mass spectrometry-based metabolomics and isotopomer analysis. Inhibitory signaling reduced aerobic glycolysis and glutaminolysis. A general scarcity across the panel of metabolites measured supported widespread metabolic regulation by PD-1. Glucose carbon fate analysis supported tricarboxylic acid cycle reliance on pyruvate carboxylation, catabolic-state fluxes into acetyl-CoA and succinyl-CoA, and a block in de novo nucleoside phosphate synthesis that was accompanied by reduced mTORC1 signaling. Nonetheless, exogenous administration of nucleosides was not sufficient to ameliorate proliferation of T-cells in the context of multiple metabolic insufficiencies due to PD-L1 treatment. Carbon fate analysis did not support the use of primarily glucose-derived carbons to fuel fatty acid beta oxidation, in contrast to reports on T-memory cells. These findings add to our understanding of metabolic dysregulation by PD-1 signaling and inform the effort to rationally develop metabolic interventions coupled with immune-checkpoint blockade for increased treatment efficacy.

Keywords: Cancer microenvironment; DNA metabolism; Metabolomics; RNA metabolism; Tumour immunology.

Abstract

Grants and funding