HTRA1 and RGS3 as Candidate Genes Associated with Shared Stromal-Immune Dysregulation across Atherosclerotic Plaques and Premature Ovarian Insufficiency.

INTRODUCTION/

Objective

Endothelial dysfunction and altered stromal-immune crosstalk are implicated in chronic inflammatory diseases. However, their roles in atherosclerotic plaque (AP) and premature ovarian insufficiency (POI) remain unclear.

Methods

The single-cell RNA-seq (scRNA-seq) data of AP and human follicular aspirates and bulk RNA-seq data for POI were obtained the Gene Expression Omnibus (GEO) database. Single-- cell analysis was performed using the Seurat package. Differential expression analysis was performed using DESeq2. High-dimensional weighted gene co-expression network analysis (hdWGCNA) was used to identify endothelial-associated modules, and the hub genes were then integrated with differentially expressed genes (DEGs). The CellChat package was used to infer cell-cell communication. Functional enrichment analysis was conducted using the clusterProfiler package.

Results

Single-cell analysis showed reduced endothelial cell abundance but increased macrophages and CD4+/CD8+ T cells in AP. Endothelial cells displayed extensive ligand-receptor crosstalk with immune and stromal cells, thereby orchestrating angiogenic and inflammatory responses. hdWGCNA identified three endothelial-associated gene modules, and integrating these modules with bulk differential expression prioritized high-temperature requirement protein A1 (HTRA1) and regulator of G protein signaling 3 (RGS3) as candidate genes. Both genes were downregulated in POI samples, and their expression levels were positively correlated with E2F/MYC/G2M cell-cycle programs and were negatively associated with IL-6/JAK-STAT3 signaling. Within the follicular niche, HTRA1 localized to theca/stromal-like follicular cells, while RGS3 was enriched in cytotoxic lymphocytes. CellChat analysis further revealed extensive bidirectional ligand-receptor interactions between theca/stromal-like follicular cells and immune populations.

Discussion

These findings suggest that endothelial dysfunction in AP and POI may share common stromal-immune features mediated by HTRA1 and RGS3. However, given the limited sample sizes and the computational nature of this study, these associations should be further validated.

Conclusion

This study developed a transcriptional gene model for AP and POI and preliminarily found that downregulation of HTRA1 and RGS3 may be associated with cell cycle and inflammatory signaling pathways.