Table 2 Metabolic analysis of T cells and CAR-T cells based on single-cell techniques

Single-cell RNA-seq

10X Genomics

CAR-T cells

5 healthy donors

41BB CAR-T cells had increased markers associated with CD8 central memory T cells and favored fatty acid metabolism

[141]

1. Bulk-seq

2. 10X Genomics

CAR-T cells

24 patients with LBCL, 137,326 residual cells

Heterogeneity of CAR T cell infusion products contributes to variation in efficacy and toxicity after axi-cel therapy

[171]

scTCR/transcriptome by 10X Genomics

peripheral blood lymphocytes after TIL infusion

1 patient with metastatic colorectal cancer

After ACT, the TILs gene expression patterns changed, but IL7R, ITGB1, KLF2 and ZNF683 remained expressed in the persistent clonotypes, compared to the non-persistent clonotypes

[161]

Single-cell Proteome

1. CyTOF

2. MIBI-TOF

CD8 T cells

1. Tumor tissue (n = 6) and healthy adjacent tissue from the same patients (n = 6)

2. Unrelated healthy donor PBMCs (n = 5) and lymph node biopsies (n = 3)

1. Three check points were identified of metabolic switching of naive human CD8⁺ T cells

2. Single-cell metabolic regulome profiling(scMEP) metabolic states associated clearly with distinct immunological phenotypes

[148]

Mass Cytometry

CD8 T cells

CAR-T cells

1. Naive or LMV infected WT C57BL/6 mice

2. 2 advanced NHL patients receiving axi-cel therapy

A distinct metabolic state in early-activate T cells (most abundant 5 days post-infection) characterized by maximal expression of glycolytic and oxidative metabolic proteins

[150]

Met-Flow

Human PBMCs

12 donors, 150,000 cells per leukocyte population

1. Metabolic remodeling occurs during T cell activation

2. T cell memory subsets show differential metabolic phenotypes; The TCM and TEM populations both expressed higher levels of ACAC, PRDX2, and CPT1A, in contrast to naive and TTEMRA subsets

[172]

Multiplexed single-cell approaches

Ins-seq

Monocytes and macrophages

7648 cells from MCA205 tumor-bearing mice

1. Arginase 1-expressing cells within tumor is a metabolic immune signature of suppressive activity

2.A novel group of Arg1 + Trem2 + regulatory myloid(Mreg) cells was found and cellular markers, metabolic activity and associated pathways were defined

[160]

1. 10X Genomics

2. Compass

Pathogenic and non-pathogenic Th17 cells

C57BL/6 wild-type mice

1. Pathogenic Th17 maintain higher aerobic glycolysis and TCA activity, whereas non-pathogenic Th17 oxidize fatty acids to produce ATP

2. Th17 pathogenicity was associated with arginine and downstream polyamine metabolism with enhanced polyamine-related enzyme expression in pathogenic Th17 and suppressed levels in Treg cells

[173]

1. scRNA-seq

2. Mass cytometry

3. scATAC-seq

Human PBMCs

1. Young/Aged healthy adults

2. Young/Aged COVID-19 patients

3. Young/Aged COVID-19 patients recovered

Immune cell landscape was reprogrammed with age and was characterized by T cell polarization from naive and memory cells to effector, cytotoxic, exhausted and regulatory cells, along with other immune cells

[163]