Clustering QC - Answer Key

Author

Will Gammerdinger

Published

July 1, 2025

Exercise 1

Hypothesize the clusters corresponding to each of the different clusters in the table:

Cell Type Clusters
CD14+ monocytes 1, 3
FCGR3A+ monocytes 10
Conventional dendritic cells 14
Plasmacytoid dendritic cells 16
Marcrophages -
B cells ?
T cells ?
CD4+ T cells ?
CD8+ T cells ?
NK cells ?
Megakaryocytes ?
Erythrocytes ?
Unknown ?

B Cells

FeaturePlot(seurat_integrated, 
            reduction = "umap", 
            features = c("CD79A", "MS4A1"), 
            order = TRUE,
            min.cutoff = 'q10', 
            label = TRUE)

B cells appear to be clusters 7, 11 and 13.

T cells

FeaturePlot(seurat_integrated, 
            reduction = "umap", 
            features = c("CD3D"), 
            order = TRUE,
            min.cutoff = 'q10', 
            label = TRUE)

T cells appear to be clusters 0, 2, 4, 5, 6 and 9.

CD4+ T cells

FeaturePlot(seurat_integrated, 
            reduction = "umap", 
            features = c("CD3D", "IL7R", "CCR7"), 
            order = TRUE,
            min.cutoff = 'q10', 
            label = TRUE)

CD4+ T cells appear to be clusters 0, 2, 4 and 6.

CD8+ T cells

FeaturePlot(seurat_integrated, 
            reduction = "umap", 
            features = c("CD3D", "CD8A"), 
            order = TRUE,
            min.cutoff = 'q10', 
            label = TRUE)

CD8+ T cells appear to be clusters 5 and 9.

NK cells

FeaturePlot(seurat_integrated, 
            reduction = "umap", 
            features = c("GNLY", "NKG7"), 
            order = TRUE,
            min.cutoff = 'q10', 
            label = TRUE)

NK cells appear to be clusters 8 and 12.

Megakaryocytes

FeaturePlot(seurat_integrated, 
            reduction = "umap", 
            features = c("PPBP"), 
            order = TRUE,
            min.cutoff = 'q10', 
            label = TRUE)

Megakaryocytes appear to be clusters 15.

Erythrocytes

FeaturePlot(seurat_integrated, 
            reduction = "umap", 
            features = c("HBB", "HBA2"), 
            order = TRUE,
            min.cutoff = 'q10', 
            label = TRUE)

Erythrocytes don’t appear to be present.


Cell Type Clusters
CD14+ monocytes 1, 3
FCGR3A+ monocytes 10
Conventional dendritic cells 14
Plasmacytoid dendritic cells 16
Marcrophages -
B cells 7, 11, 13
T cells 0, 2, 4, 5, 6, 9
CD4+ T cells 0, 2, 4, 6
CD8+ T cells 5, 9
NK cells 8, 12
Megakaryocytes 15
Erythrocytes -