Abstract
Background
The existence of stem/progenitor cells in the lens epithelium has been demonstrated, but their identification remains challenging. Accurate identifcation requires advanced technologies and a comprehensive understanding of lens epithelial cell (LEC) subtypes, presenting a signifcant challenge in age-related cataract research.
Methods
Eight pairs of human donor lens epithelium samples were collected for single-cell RNA sequencing
(scRNA-seq). This included four non-aged (<65 years) and four aged (>65 years) individuals. Subsequent analyses
involved cell (sub)type characterization, trajectory inference, and cell–cell communication. Experimental validation
was conducted through transcriptome sequencing and immunofuorescence on human lenses, lens organoids, rabbit regenerated lenses, mouse lenses, and cell lines.
Results
Six groups were identifed via UMAP mapping of scRNA-seq data: four LECs, one lens fber cells (LFCs),
and one immune cells. One of the four LEC clusters exhibited a distinct gene expression profle and was identifed
as transient amplifying cells (TACs). TACs specifcally express TOP2A and are localized at the lens equator. CytoTRACE
analysis to the LEC and LFC data sets provided a diferentiation trajectory. The TAC group was determined as stage 2
in the trajectory and LFCs last. The 3 sub groups were labelled early, mid and late LECs and corresponded to stage 1,
3 and 4 in the path. While cell population demographics remained stable with age, transcriptomic changes in LECs
were observed, including weaker intercellular crosstalk and adhesion, and fewer TACs in S phase. Lens progenitor-like
cells (LPLCs) were identifed as a sub-population in early LECs and express ID1. In addition, pleiotrophin (PTN) signaling was prevalent at all diferentiation stages, with a notable weakening of PTN signaling in aged LPLCs.
Conclusions
This study identifed four subclasses of LECs within the human lens epithelium that follow a progressive staged development pathway from progenitor cells to mature LECs. TOP2A can serve as a biomarker for TAC
The existence of stem/progenitor cells in the lens epithelium has been demonstrated, but their identification remains challenging. Accurate identifcation requires advanced technologies and a comprehensive understanding of lens epithelial cell (LEC) subtypes, presenting a signifcant challenge in age-related cataract research.
Methods
Eight pairs of human donor lens epithelium samples were collected for single-cell RNA sequencing
(scRNA-seq). This included four non-aged (<65 years) and four aged (>65 years) individuals. Subsequent analyses
involved cell (sub)type characterization, trajectory inference, and cell–cell communication. Experimental validation
was conducted through transcriptome sequencing and immunofuorescence on human lenses, lens organoids, rabbit regenerated lenses, mouse lenses, and cell lines.
Results
Six groups were identifed via UMAP mapping of scRNA-seq data: four LECs, one lens fber cells (LFCs),
and one immune cells. One of the four LEC clusters exhibited a distinct gene expression profle and was identifed
as transient amplifying cells (TACs). TACs specifcally express TOP2A and are localized at the lens equator. CytoTRACE
analysis to the LEC and LFC data sets provided a diferentiation trajectory. The TAC group was determined as stage 2
in the trajectory and LFCs last. The 3 sub groups were labelled early, mid and late LECs and corresponded to stage 1,
3 and 4 in the path. While cell population demographics remained stable with age, transcriptomic changes in LECs
were observed, including weaker intercellular crosstalk and adhesion, and fewer TACs in S phase. Lens progenitor-like
cells (LPLCs) were identifed as a sub-population in early LECs and express ID1. In addition, pleiotrophin (PTN) signaling was prevalent at all diferentiation stages, with a notable weakening of PTN signaling in aged LPLCs.
Conclusions
This study identifed four subclasses of LECs within the human lens epithelium that follow a progressive staged development pathway from progenitor cells to mature LECs. TOP2A can serve as a biomarker for TAC
| Original language | English |
|---|---|
| Journal | Stem Cell Research and Therapy |
| Publication status | Published - 1 Jul 2025 |
Keywords
- scRNA-seq
- Aging
- Lens epithelial cell
- Transient amplifying cell
- Lens stem cell