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Perrien, D. S.

Publications and source records attributed to Perrien, D. S..

2 recordsLinked to original sources

Gut microbiome-dependent IL-1 signaling is a mediator of ACVR1R206H-driven heterotopic ossification

Inflammatory diseases cause significant morbidity and mortality, but their pathobiology is often difficult to dissect due to complex genetic-environmental interactions. Genetic forms of heterotopic ossification, such as fibrodysplasia ossificans progressiva (FOP), reduce genetic variability, allowing careful dissection of non-genetic drivers of inflammation. While >95% of FOP patients harbor the ACVR1R206H mutation, patients exhibit significant variability in disease progression, suggesting a role of environmental drivers. Here, we identify the gut microbiome as a regulator of inflammation-driven HO in FOP. Metagenomic profiling of cohabitating FOP/unaffected sibling pairs revealed a pathogenic gut microbiome profile in FOP patients (Bray-Curtis, p < 0.05). In Pdgfr-Cre/Acvr1R206H (FOP) mice, gut microbiome ablation by antibiotics reduced spontaneous HO formation (47.4% reduction, p < 0.05) and reduced plasma IL-1 pathway activity. IL-1{beta} blockade in FOP mice suppressed trauma-induced HO formation. These findings identify a gut microbiome-IL-1-HO axis with modifiable targets for developing treatments for HO and related inflammatory conditions. One Sentence SummaryAntibiotic disruption of the gut microbiome reduces HO in FOP mice via an IL-1 mediated pathway.

immunology↗

IFT20 is critical for early chondrogenesis during endochondral ossification

Ciliogenic components, such as the family of intraflagellar transport (IFT) proteins, are recognized to play key roles in endochondral ossification, a critical process to form most bones. However, it remains unclear how each IFT protein performs its unique function to regulate endochondral ossification. Here, we show that intraflagellar transport 20 (IFT20) is required for early chondrogenesis. Utilizing three osteo-chondrocyte lineage-specific Cre mice (Prx1-Cre, Col2-Cre and Aggrecan-CreERT2), we deleted Ift20 to examine its function. While chondrocyte-specific Ift20 deletion with Col2-Cre or Aggrecan-CreERT2 drivers did not cause overt skeletal defects, mesoderm-specific Ift20 deletion using Prx1-Cre (Ift20:Prx1-Cre) resulted in shortened limb outgrowth. Although primary cilia were not formed in Ift20:Prx1-Cre mice, ciliary Hedgehog signaling was only moderately affected. Interestingly, loss of Ift20 lead to upregulation of Fgf18 expression resulting in ERK1/2 activation and sustained Sox9 expression, thus preventing endochondral ossification. Inhibition of enhanced phospho-ERK1/2 activation partially rescued defective chondrogenesis in Ift20 mutant cells, supporting an important role for FGF signaling. Our findings demonstrate a novel mechanism of IFT20 in early chondrogenesis during endochondral ossification.

developmental biology↗