Naslov
RNA-sequencing of osteoclast progenitor subsets in a murine model of arthritis

Autori
Aničić, Sara ; Filipović, Maša ; Flegar, Darja ; Šisl, Dino ; Kelava, Tomislav ; Kovačić, Nataša ; Grčević, Danka ; Šućur, Alan

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
3rd Regional Congress of Physiological Societies and 5th Congress of Croatian Physiological Society / - , 2022, 50-50

Skup
3rd Regional Congress of Physiological Societies and 5th Congress of Croatian Physiological Society

Mjesto i datum
NP Plitvička jezera, Hrvatska, 22.09.2022. - 24.09.2022

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Domaća recenzija

Ključne riječi
RNA sequencing ; chemokine receptor ; flow cytometry ; gene expression ; mouse arthritis ; osteoclast differentiation ; osteoclast progenitor (OCP) ; qPCR

Sažetak
CroatiaOsteoclasts are multinuclear bone resorbing cells differentiated from monocyte/macrophage lineage of hematopoietic cells. They form by fusion of mononuclear osteoclast progenitors (OCPs), and mediate increased bone loss in arthritis. Our research group identified murine periarticular bone marrow OCPs as CD45+Ly6G-CD3- B220-NK1.1-CD11b-/loCD115+ cells using flow cytometry. They were further sepa-rated by the level of chemokine receptor CCR2 expression, into CCR2hi and CCR2lo subsets. We previ-ously showed that these subsets are significantly expanded in collagen-induced arthrtis (CIA). Our aim was to characterize these OCP subsets by RNA-sequencing. Therefore, we sorted CCR2hi and CCR2lo OCPs from control and CIA mice (n=4 for every group), and performed RNA extraction, library prepara-tion and RNA sequencing. For transcriptome profiling, we first aligned raw sequencing reads to the mouse reference genome, and then performed gene set enrichment analysis to evaluate the differential gene expression profile across samples. Principal component analysis showed that transcriptomes differed mostly based on CCR2 expression, and less depending on intervention (CIA/control). Our stringent analysis criteria (log2 fold change≥2) revealed total of 862 differentially expressed genes between CCR2hi and CCR2lo OCPs, included within several biological pathways. Top enriched path-ways in CCR2hi OCPs in both CIA and control were osteoclast differentiation, chemokine and NOD-like receptor signaling pathways, while ribosomal biosynthetic pathways were downregulated compared to CCR2lo OCPs. In addition, several inflammatory pathways were enriched in CCR2hi subset only in CIA, including Staphylococcus aureus infection, Toll-like receptor and TNF signaling pathways. Genes selected from the enriched pathways were further validated by qPCR. To conclude, CCR2hi was more altered than CCR2lo subset in CIA compared to control. CCR2hi OCPs posses greater osteoclastogenic and migratory potential than CCR2lo OCPs. Furthermore, CCR2hi subset becomes specifically respon-sive to inflammatory conditions in CIA. These results indicate that CCR2hi OCPs could be mainly responsible for enhanced osteoresorption in arthritis.

Izvorni jezik
Engleski

Znanstvena područja
Kliničke medicinske znanosti

POVEZANOST RADA