Fig. 4
From: The PD-L1 metabolic interactome intersects with choline metabolism and inflammation
Consequences of Chk-α and PD-L1 downregulation on lipids. a Representative high-resolution 1H MR spectra obtained from the lipid phase of MDA-MB 231 cells. Spectra are displayed from untreated cells (black), cells transfected with 100 nM luciferase siRNA (light gray) for 48 h, cells transfected with 100 nM Chk-α siRNA (orange) for 48 h, cells transfected with 100 nM PD-L1 siRNA #1 (blue) for 48 h, and cells transfected with a mixture of 50 nM PD-L1 #1 and 50 nM Chk-α siRNA (red) for 48 h. b Metabolic heat map, generated from quantitative analysis of high-resolution 1H MR spectral data of the lipid phase, displaying differences in the lipid profile of MDA-MB-231 cells. The heat map displays metabolites from untreated cells, cells transfected with 100 nM luciferase siRNA for 48 h, cells transfected with 100 nM Chk-α siRNA for 48 h, cells transfected with 100 nM PD-L1 siRNA #1 for 48 h, and cells transfected with a mixture of 50 nM PD-L1 #1 and 50 nM Chk-α siRNA for 48 h. Heat maps were created as described above from 3 to 6 replicates per group. Lipids (-CH3), methyl groups of fatty acids; Lipids (-CH2-), methylene groups of fatty acids (truncated); OOC-CH2, methylene groups at the α position of the carboxylic function; OOC-CH2-CH2, methylene groups at the β position of the carboxylic function; ARA, arachidonic acid; EPA, eicosapentaenoic acid; PtdEA, phosphatidylethanolamine; PtdCholine, phosphatidylcholine; (CH=CH-CH2-CH=CH)n, diallylic methylene protons; CH=CH-CH2, methylene groups at the α position of a double bond; CH=CH, fatty acid double bonds. *p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001, compared to the control group (see also Supplementary Table 2)