satijalab / seurat

R toolkit for single cell genomics
http://www.satijalab.org/seurat
Other
2.29k stars 915 forks source link

Integration with/without SCT #5999

Closed cgraham13 closed 2 years ago

cgraham13 commented 2 years ago

Hello,

I am integrating 3 samples. Each of the samples have been normalized with SCTransform and they all look good. I am having some issues when I am integrating the samples. I have tried 2 different approaches:

1) Integration with SCT

features <- SelectIntegrationFeatures(object.list = ntd.list, nfeatures = 3000) NTD.integrated <- PrepSCTIntegration(object.list = ntd.list, anchor.features = features) anchors <- FindIntegrationAnchors( object.list = NTD.integrated, object.list = ntd.list, normalization.method = "SCT", anchor.features = features ) NTD.integrated <- IntegrateData(anchorset = anchors, normalization.method = "SCT" )

NTD.integrated <- RunPCA(NTD.integrated) NTD.integrated <- RunUMAP(NTD.integrated, reduction = "pca", dims = 1:30) NTD.integrated <- FindNeighbors(NTD.integrated, reduction = "pca", dims = 1:30) NTD.integrated <- FindClusters(NTD.integrated, resolution = c(0.5))

2) Integration without SCT

features <- SelectIntegrationFeatures(object.list = ntd.list, nfeatures = 2000) anchors <- FindIntegrationAnchors( object.list = NTD.integrated, object.list = ntd.list, anchor.features = features ) NTD.integrated <- IntegrateData(anchorset = anchors )

NTD.integrated <- ScaleData(NTD.integrated, verbose = FALSE) NTD.integrated <- RunPCA(NTD.integrated) NTD.integrated <- RunUMAP(NTD.integrated, reduction = "pca", dims = 1:30) NTD.integrated <- FindNeighbors(NTD.integrated, reduction = "pca", dims = 1:30) NTD.integrated <- FindClusters(NTD.integrated, resolution = c(0.5))

When I look at the clustering and UMAP with both approaches they are very different. The SCT UMAP has a lot of small clusters and the integration without SCT looks more realistic. My main question is, is it ok to integrate without SCT when the samples have been normalized individually using SCTransform?

I have attached the UMAPs below for reference.

Thanks in advance!

Carly

MoA-UMAP-NTD-Normalized.pdf MoA-UMAP-NTD-SCTInt.pdf

saketkc commented 2 years ago

While it is fine to integrate without SCT, you can also consider using the v2 flavor for SCT.