 Studies were incorporated in a barcode, matrix, feature format. This format can be found on the 
                        
                        10x Genomics website
                         
                        for processing of single cell studies to obtain the gene expression matrices. 
                        For each study, the metadata incorporated in GEO were manually curated into profiles and the samples were separated based on applicable groups and conditions. 
                        The expression data from the cells for the samples within the same profile and condition were aggregated into an expression matrix with the cell barcodes having the sample name appended to it to ensure unique cell names.
                    
                        Studies were incorporated in a barcode, matrix, feature format. This format can be found on the 
                        
                        10x Genomics website
                         
                        for processing of single cell studies to obtain the gene expression matrices. 
                        For each study, the metadata incorporated in GEO were manually curated into profiles and the samples were separated based on applicable groups and conditions. 
                        The expression data from the cells for the samples within the same profile and condition were aggregated into an expression matrix with the cell barcodes having the sample name appended to it to ensure unique cell names.
                    
                Submission Date: Oct 15, 2019
Summary: The generation of pancreatic cell types from renewable cell sources holds promise for cell replacement therapies for diabetes. Although most effort has focused on generating pancreatic beta cells, there is considerable evidence that glucagon secreting alpha cells are critically involved in disease progression and proper glucose control. Here we report on the generation of stem cell-derived human pancreatic alpha (SC-alpha) cells from pluripotent stem cells via a transient pre-alpha cell intermediate. These pre-alpha cells exhibit a transcriptional profile similar to mature alpha cells and although they produce proinsulin protein, they do not secrete significant amounts of processed insulin. The resulting SC-alpha cells do not express insulin, share an ultrastructure similar to cadaveric alpha cells, express and secrete glucagon in response to glucose and some glucagon secretagogues, and elevate blood glucose upon transplantation in mice.
GEO Accession ID: GSE138857
PMID: 32382023
 Preprocessing and downstream analysis were computed using the scanpy Python library and the
                        steps of processing followed the Seurat vignette. Cells and genes with no expression or very low expression were 
                        removed from the dataset based on a predefined threshold. The data was then normalized across the expression within the cells and log normalized. The top 2000 highly variable genes were extracted to be used for downstream analysis. 
                        For each of these aggregated data matrices, the clusters were computed using the leiden algorithm. Scanpy was then used to compute the PCA, t-SNE, and UMAPs.
                        The points in the plots are labelled by their corresponding cell type labels. The cell type labels were computed using the wilcoxon method as the differential gene expression method.
                        The top 250 genes were then used for enrichment analysis against the CellMarker library in order to determine the most appropriate cell type label with the lowest p-value.
                    
                        Preprocessing and downstream analysis were computed using the scanpy Python library and the
                        steps of processing followed the Seurat vignette. Cells and genes with no expression or very low expression were 
                        removed from the dataset based on a predefined threshold. The data was then normalized across the expression within the cells and log normalized. The top 2000 highly variable genes were extracted to be used for downstream analysis. 
                        For each of these aggregated data matrices, the clusters were computed using the leiden algorithm. Scanpy was then used to compute the PCA, t-SNE, and UMAPs.
                        The points in the plots are labelled by their corresponding cell type labels. The cell type labels were computed using the wilcoxon method as the differential gene expression method.
                        The top 250 genes were then used for enrichment analysis against the CellMarker library in order to determine the most appropriate cell type label with the lowest p-value.
                    
                Select conditions below to toggle them from the plot:
| Cell Types | Cell Samples | 
|---|---|
 Differential gene expression can be computed for a single cell type labeled group of cells vs the rest. 
                        These include wilcoxon,
                        DESeq2, or characteristic direction.
                    
                        Differential gene expression can be computed for a single cell type labeled group of cells vs the rest. 
                        These include wilcoxon,
                        DESeq2, or characteristic direction.