Multi-transcriptomic Profiling Reveals Novel Molecular Mediators During Abdominal Aortic Aneurysm Expansion.

Abdominal aortic aneurysm (AAA), a life-threatening condition associated with high morbidity and mortality rates, is despite decades of intense research still mostly treated by surgical repair as currently no medical therapy is available. Long non-coding RNAs (lncRNAs) are highly cell type specific and potential molecular disease modulators, posing potential drug targets. We performed single cell (sc) RNA and combined total (bulk) RNA sequencing to study the transcriptome of AAAs from patients undergoing open aortic repair. Further, we implemented hybridization-based RNA in situ sequencing (HybRISS) to localize highly intriguing genes within the tissue.In this current study, we examined three different sequencing datasets (total RNA from dilated vs. non- dilated AAA specimen from an individual patient each, AAA vs. control from individual patients and one scRNA-seq dataset). Six lncRNAs could be cross-referenced between all three datasets. All of these lncRNAs presented a cell-type specific expression pattern, with three lncRNAs being highly enriched within the SMC cluster. We found all newly identified lncRNAs conserved in our bulk and scRNA-seq datasets of experimentally-induced AAA in mice and LDLR-deficient Yucatan mini-pigs. Further, potential novel regulator genes could be visualized in human AAA tissue sections using HybRISS to resolve their distinct location and co-expression pattern within the diseased tissue. In summary, our approach utilizing dilated and non-dilated human tissue specimens, different preclinical models and resulting datasets demonstrate that combining bulk Seq, scRNA-Seq data and spatially resolved sequencing methods are powerful tools to detect and describe novel lncRNAs as disease modulators.