CellSIUS provides sensitive and specific detection of rare cell populations from complex single-cell RNA-seq data

Area of Science:

• Genomics
• Computational Biology
• Developmental Biology

Background:

• Single-cell RNA sequencing (scRNA-seq) enables high-resolution analysis of cellular heterogeneity.
• Identifying rare cell populations within complex scRNA-seq datasets remains a significant methodological challenge.
• Existing algorithms often lack the specificity and selectivity required for robust rare cell type discovery.

Purpose of the Study:

• To introduce CellSIUS (Cell Subtype Identification from Upregulated gene Sets), a novel computational tool designed to address the gap in rare cell population identification for scRNA-seq data.
• To evaluate the performance of CellSIUS against existing methods using both synthetic and complex biological datasets.
• To apply CellSIUS to investigate cellular heterogeneity during human pluripotent stem cell differentiation for deep-layer corticogenesis.

Main Methods:

• Development of CellSIUS, a novel algorithm leveraging upregulated gene sets for rare cell identification.
• Comparative analysis of CellSIUS with existing rare cell identification algorithms on synthetic and real-world scRNA-seq data.
• Application of CellSIUS to analyze scRNA-seq data from a human pluripotent stem cell differentiation protocol.

Main Results:

• CellSIUS demonstrates superior performance in specificity and selectivity for identifying rare cell types compared to current algorithms.
• The tool accurately identifies transcriptomic signatures of rare cell populations in both synthetic and complex biological data.
• Analysis of human corticogenesis revealed previously unrecognized complexity and novel rare cell populations within stem cell-derived populations.

Conclusions:

• CellSIUS effectively fills a critical methodological gap in rare cell population identification from scRNA-seq data.
• The tool facilitates the discovery of novel rare cell populations and their associated signature genes.
• CellSIUS provides a powerful means to study the in vitro roles of these rare cells in health and disease.