Abstract Number: VPB0161
Meeting: ISTH 2022 Congress
Theme: Vascular Biology » Epigenetics, OMICs and Bioinformatics
Background: Synovial molecular processes after hemarthrosis are poorly understood. Emerging evidence suggests that FVIII-Fc fusion protein, containing the Fc-portion of immunoglobulin, may mitigate joint inflammation.
Aims: To explore synovial differential gene expression (DGE) and molecular pathways after hemarthrosis in FVIIIKO mice when treated with recombinant human factor VIII (rhFVIII) compared to murine Fc-FVIII (mFcFVIII).
Methods: Hemarthrosis was induced by needle puncture in mice treated with saline, 100 IU/kg mFcFVIII (Fc species specificity) or 120 IU/kg rhFVIII (accounting for t1/2 differences) administered intravenously 2hrs before and 6hrs after injury. Synovial RNA sequencing (day 3 or 14 post-injury (n=3-5)) was performed with Illumina NextSeq500, STAR alignment to mm10, RSEM gene quantification, Limma DGE analysis (model: ~0 + time + treatment; adjusted p-value < 0.05), gprofiler enrichment analysis using KEGG and Reactome databases. Saline-treated groups were compared to untreated and FVIII treated groups.
Results: RhFVIII and mFcFVIII prevented hemarthrosis. On day 3, 2349 differentially expressed genes (DEGs) were related to hemarthrosis/injury; furthermore, of these, 956 DEGs were affected by FVIII (387 rhFVIII-specific, 106 mFcFVIII-specific, 463 shared). Total DGE was lower on day 14 with 1606 related to injury (20 rhFVIII-specific, 95 mFcFVIII-specific, 40 shared).
DEGs modulated by both FVIII preparations, unrelated to hemarthrosis/injury, shared pathways involved in tissue metabolism/repair. Other pathways were unique to each treatment. Notably on day 14, only mFcFVIII affected collagen/tissue repair, while both FVIII-preparations affected immune regulatory pathways for the subset of DEGs unrelated to hemarthrosis/injury (“off-target”), differing in number and type. “On-target” injury-related DEGs with mFcFVIII were important to protein composition via the Ribosome and Spliceosome pathways (Fig. 1 & 2).
Conclusion(s): FVIII preparation-specific molecular processes after hemarthrosis differed, suggesting that the type of FVIII preparation may have implications beyond hemostasis control.
To cite this abstract in AMA style:
Chumappumkal Joseph B, Whisenant T, J Cooke E, Zhou J, Ruiz S, Rattanamansuang D, von Drygalski A. Gene Expression after Hemarthrosis Differs Among Recombinant FVIII and FVIII-Fc Fusion Replacement in FVIII-Deficient Mice [abstract]. https://abstracts.isth.org/abstract/gene-expression-after-hemarthrosis-differs-among-recombinant-fviii-and-fviii-fc-fusion-replacement-in-fviii-deficient-mice/. Accessed March 21, 2024.« Back to ISTH 2022 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/gene-expression-after-hemarthrosis-differs-among-recombinant-fviii-and-fviii-fc-fusion-replacement-in-fviii-deficient-mice/