Advances in molecular profiling have opened up the possibility to map the expression of genes in cells, tissues, and organs in the human body. Here, a team led by researchers at the KTH-Royal Institute of Technology combined single-cell transcriptomics analysis with spatial antibody-based protein profiling to create a high-resolution single–cell type map of human tissues. An open access atlas has been launched to allow researchers to explore the expression of human protein-coding genes in 192 individual cell type clusters. An expression specificity classification was performed to determine the number of genes elevated in each cell type, allowing comparisons with bulk transcriptomics data. The analysis highlights distinct expression clusters corresponding to cell types sharing similar functions, both within the same organs and between organs.
Annotating 51 cell types from 13 tissues using single-cell transcriptomics data
(A) scRNA-seq data from 13 tissues and blood [peripheral blood mononuclear cells (PBMCs)] were processed through a clustering algorithm, and each cluster was annotated using known markers. All cells from a cluster were pooled, and the average transcript per million was calculated for all protein-coding genes. (B) UMAP plot showing the relationship of all cell types from all analyzed tissues. The color-coding corresponds to 12 main cell type groups. (C) Cell type dendrogram showing the relationship between all 51 identified main single cell types based on genome-wide expression.
Availability – http://www.proteinatlas.org/humanproteome/celltype