Distinguishing cell-cell complexes from dual lineage cells using single-cell transcriptomics is not trivial

Distinguishing between dual lineage cells and cell-cell complexes remains a challenge in single-cell RNA sequencing. Prior research has shown that cell-cell complexes can mimic dual lineage expression patterns. This uncertainty has driven efforts to refine analytical approaches. Jie et al. argue that their DE cell population represents dual lineage co-expression. However, no prior work had resolved how to differentiate these from complexes. Their claim relies on gene signatures. But gene signatures alone may not confirm cell type. This gap motivated further investigation into DE cell composition. The need for clarity is essential for accurate biological interpretation.

This study aims to evaluate the validity of Jie et al.'s claim that DE cells are dual lineage co-expressing cells. The specific problem lies in the ambiguity of distinguishing dual lineage cells from cell-cell complexes. The motivation stems from the limitations of gene signature analysis. The authors propose that gene signatures may not be sufficient evidence. They aim to test whether DE cells could represent cell aggregates. The study focuses on transcriptomic features of DE cells. It seeks to identify markers that distinguish dual lineage cells from complexes. The goal is to provide a more accurate interpretation of scRNAseq data.

The researchers analyzed the gene expression profiles of DE cells using single-cell RNA sequencing data. They compared the gene signature of DE cells to known lineage-specific markers. The approach included identifying genes from the myeloid lineage in DE cells. They examined whether these genes suggest a triple-lineage co-expression or a three-component aggregate. The study also assessed transcriptomic features of DE cells. These features included the average expression of B- and T-cell specific genes. The number of detected genes per cell was another key metric. The analysis focused on whether these features align with cell-cell complexes.

The study found that the DE cell gene signature includes myeloid lineage genes. This suggests either triple-lineage co-expression or a three-component aggregate. The average expression of B- and T-cell specific genes was lower in DE cells. This is consistent with cell-cell complexes rather than dual lineage cells. DE cells also had a higher number of detected genes per cell. This is a known feature of cell-cell aggregates in scRNAseq data. The presence of these features indicates that DE cells may not be dual lineage. The findings challenge the claim that DE cells are biologically distinct.

The authors conclude that gene signatures alone cannot confirm dual lineage co-expression in DE cells. Their findings suggest that DE cells may represent cell-cell complexes. The presence of myeloid lineage genes supports this possibility. The lower expression of B- and T-cell specific genes is a key indicator. The higher number of detected genes per cell also aligns with complex formation. The study does not propose new drug targets or future directions. It emphasizes the limitations of current scRNAseq analysis methods. The authors suggest that additional validation is needed to confirm DE cell identity.