SARS-CoV-2 spike receptor-binding domain is internalized and promotes protein ISGylation in human induced pluripotent stem cell-derived cardiomyocytes

Although an increased risk of myocarditis has been observed after vaccination with mRNA encoding severe acute respiratory syndrome coronavirus 2 spike protein, its underlying mechanism has not been elucidated. This study investigated the direct effects of spike receptor-binding domain (S-RBD) on human cardiomyocytes differentiated from induced pluripotent stem cells (iPSC-CMs). Immunostaining experiments using ACE2 wild-type (WT) and knockout (KO) iPSC-CMs treated with purified S-RBD demonstrated that S-RBD was bound to ACE2 and internalized into the subcellular space in the iPSC-CMs, depending on ACE2. Immunostaining combined with live cell imaging using a recombinant S-RBD fused to the superfolder GFP (S-RBD-sfGFP) demonstrated that S-RBD was bound to the cell membrane, co-localized with RAB5A, and then delivered from the endosomes to the lysosomes in iPSC-CMs. Quantitative PCR array analysis followed by single cell RNA sequence analysis clarified that S-RBD-sfGFP treatment significantly upregulated the NF-kβ pathway-related gene (CXCL1) in the differentiated non-cardiomyocytes, while upregulated interferon (IFN)-responsive genes (IFI6, ISG15, and IFITM3) in the matured cardiomyocytes. S-RBD-sfGFP treatment promoted protein ISGylation, an ISG15-mediated post-translational modification in ACE2-WT-iPSC-CMs, which was suppressed in ACE2-KO-iPSC-CMs. Our experimental study demonstrates that S-RBD is internalized through the endolysosomal pathway, which upregulates IFN-responsive genes and promotes ISGylation in the iPSC-CMs.Okuno S., Higo S., Kondo T., et al. SARS-CoV-2 spike receptor-binding domain is internalized and promotes protein ISGylation in human induced pluripotent stem cell-derived cardiomyocytes. Scientific Reports 13, 21397 (2023); https://doi.org/10.1038/s41598-023-48084-7

External Pancreatic Juice Drainage Through a Percutaneous Endoscopic Drainage Tube for the Patient With a Postoperative Pancreatic Juice Leakage

Percutaneous endoscopic gastrostomy (PEG) has been widely accepted for patients who have no swallowing ability but have an intact gut. Its clinical application is mainly for nutritional support and decompression of the intestine in patients with bowel obstruction. In this paper, we report external pancreatic juice drainage through a percutaneous endoscopic drainage tube in a patient with postoperative pancreatic juice leakage. Soon after this procedure, pancreatic juice leakage subsided. This procedure was minimally invasive for the patient and may be a new application of PEG to maintain the good quality of life (QOL) in a patient with pancreatic juice leakage

Case report: Usefulness of angioscopy in determining antiplatelet drug reduction after carotid artery stenting

We report a case in which neointima was confirmed by angioscopy and antiplatelet drug administration was reduced 2 months after carotid artery stenting (CAS). A patient in their 80s was scheduled to undergo resection for renal cancer; however, he also had right cervical internal carotid artery stenosis. Because this was a risk for general anesthesia, CAS was performed after first starting dual antiplatelet therapy. Urologically, early reduction of antiplatelet drugs was necessary for a nephrectomy. Although no obvious neointima could be identified on ultrasound 2 months after CAS, thin neointima was observed using angioscopy. Based on the above results, we reduced the antiplatelet drug administration, and then the nephrectomy was performed. Ultimately, no cerebral infarction occurred in the perioperative or postoperative periods. Angioscopy allows for visual confirmation of thin neointima. If sufficient neointima can be confirmed, antiplatelet drug reduction can be performed more safely and reliably

Fatal persistent methicillin-resistant bacteremia and vascular graft infections complicated with the formation of multiple abscesses despite aggressive medical therapy

A 40-year-old man underwent ascending aorta replacement for an acute type A aortic dissection. After the operations, methicillin-resistant Staphylococcus aureus was identified in sputum and blood cultures. Although anti-methicillin-resistant Staphylococcus aureus drugs were administered, most of the intermittent blood cultures remained positive. The focus of methicillin-resistant Staphylococcus aureus infection was not evident in the early stages, and no specific symptoms such as abscess or endocarditis were observed. However, abscesses in the brain, mediastinum and spleen were found 3 years after the operation. The minimum inhibitory concentration of vancomycin gradually increased from 1 to 4 µg/mL during the course of treatment. This case provides evidence for a potential role of combination therapy

Presence of increased inflammatory infiltrates accompanied by activated dendritic cells in the left atrium in rheumatic heart disease.

AIMS:Left atrial (LA) structural remodelling develops in rheumatic heart disease (RHD) according to the disease severity of the mitral valve and the presence of atrial fibrillation. Sustained active inflammation has been previously reported in the LA of patients with RHD, suggesting a direct role of cell-mediated immunity in the pathogenesis of LA remodelling. Dendritic cells (DCs) have a major antigen-presenting role, and are known as crucial modulators of innate and adaptive immunity. We investigated whether DCs are involved in the pathogenesis of LA remodelling in RHD. METHODS AND RESULTS:Immunohistochemical analyses were performed using antibodies to CD11c, CD209 and CD80 as markers of myeloid DCs, migratory-active DCs, mature DCs and infiltrated inflammatory cells including T lymphocytes (CD3) and M1 (CD68; pro-inflammatory profile) and M2 (CD163; pro-resolution profile) macrophages. Furthermore, tenascin-C, an extracellular matrix (ECM) protein that appears during ECM remodelling and inflammatory response, was examined. Infiltrated myeloid DCs, migratory-active DCs, mature DCs and other inflammatory infiltrates including T lymphocytes and M1 and M2 macrophages, were significantly higher in the RHD group than the non-RHD group. The positive area fraction for tenascin-C was significantly higher in the RHD group than in the non-RHD group. CONCLUSION:Our histological findings suggest that inflammation may persist long after a bout of rheumatic fever, ultimately leading to ECM remodelling. We identified and quantitatively assessed several subsets of DCs and other immunocompetent cells, and our results indicated that activation of DCs has some role in persistence of LA inflammation in patients with chronic RHD

Efficacy of Angioscopy for the Detection of Mobile Carotid Artery Lesions

Case presentation A 78‐year‐old man with a mobile lesion was diagnosed with thrombus using carotid ultrasonography, but the lesion was not completely resolved with dual antiplatelet and anticoagulation therapy. Direct visualization by angioscopy showed a white mobile plaque. The carotid artery was stented with a double‐layered stent, as the plaque persisted despite continuing the medical treatment and was linked to an increased risk of cerebral embolism. The plaque was attached to the arterial wall, and it subsequently disappeared. The patient recovered well and no further emboli were observed. Conclusions Angioscopy is effective for identifying lesions under direct vision. The characteristics and dynamics of plaques may be viewed via angioscopy, which aids in making treatment‐related decisions, particularly in the case of carotid artery plaques

Human induced pluripotent stem cell-derived closed-loop cardiac tissue for drug assessment

Summary: Human iPSC-derived cardiomyocytes (hiPSC-CMs) exhibit functional immaturity, potentially impacting their suitability for assessing drug proarrhythmic potential. We previously devised a traveling wave (TW) system to promote maturation in 3D cardiac tissue. To align with current drug assessment paradigms (CiPA and JiCSA), necessitating a 2D monolayer cardiac tissue, we integrated the TW system with a multi-electrode array. This gave rise to a hiPSC-derived closed-loop cardiac tissue (iCT), enabling spontaneous TW initiation and swift pacing of cardiomyocytes from various cell lines. The TW-paced cardiomyocytes demonstrated heightened sarcomeric and functional maturation, exhibiting enhanced response to isoproterenol. Moreover, these cells showcased diminished sensitivity to verapamil and maintained low arrhythmia rates with ranolazine—two drugs associated with a low risk of torsades de pointes (TdP). Notably, the TW group displayed increased arrhythmia rates with high and intermediate risk TdP drugs (quinidine and pimozide), underscoring the potential utility of this system in drug assessment applications