We describe a novel therapeutic approach for cirrhosis using mesenchymal stem cells (MSCs) and colony‐stimulating factor‐1‐induced bone marrow‐derived macrophages (id‐BMMs) and analyze the mechanisms underlying fibrosis improvement and regeneration. Mouse MSCs and id‐BMMs were cultured from mouse bone marrow and their interactions analyzed in vitro. MSCs, id‐BMMs, and a combination therapy using MSCs and id‐BMMs were administered to mice with CCl4‐induced cirrhosis. Fibrosis regression, liver regeneration, and liver‐migrating host cells were evaluated. Administered cell behavior was also tracked by intravital imaging. In coculture, MSCs induced switching of id‐BMMs toward the M2 phenotype with high phagocytic activity. In vivo, the combination therapy reduced liver fibrosis (associated with increased matrix metalloproteinases expression), increased hepatocyte proliferation (associated with increased hepatocyte growth factor, vascular endothelial growth factor, and oncostatin M in the liver), and reduced blood levels of liver enzymes, more effectively than MSCs or id‐BMMs monotherapy. Intravital imaging showed that after combination cell administration, a large number of id‐BMMs, which phagocytosed hepatocyte debris and were retained in the liver for more than 7 days, along with a few MSCs, the majority of which were trapped in the lung, migrated to the fibrotic area in the liver. Host macrophages and neutrophils infiltrated after combination therapy and contributed to liver fibrosis regression and promoted regeneration along with administered cells. Indirect effector MSCs and direct effector id‐BMMs synergistically improved cirrhosis along with host cells in mice. These studies pave the way for new treatments for cirrhosis. Stem Cells Translational Medicine 2019;8:271&284

BackgroundThere is a lack of consensus regarding the risk of postoperative hemorrhage in patients on antithrombotic therapy who undergo endoscopic submucosal dissection (ESD).We examined postoperative bleeding rates and risk factors for postoperative hemorrhage from post-ESD gastric ulcers in patients on antithrombotic therapy.MethodsThe subjects of this study were 833 patients who underwent ESD of gastric tumors. Of these, 743 were not on antithrombotic therapy and 90 were on some form of antithrombotic therapy (46 on low-dose aspirin (LDA) only, 23 on LDA + thienopyridine, and 21 on LDA + warfarin). All patients commenced proton pump inhibitor (PPI) therapy immediately postoperatively. Antiplatelet agents were discontinued for 7 days preoperatively and postoperative Day 1, and anticoagulants for 5 days preoperatively and postoperative Day 1.ResultsThe postoperative bleeding rate in the antithrombotic group was 23.3%, significantly higher than the 2.0% observed in the non-antithrombotic group. Significant differences were seen in patients in the antithrombotic group with and without postoperative bleeding according to ESD duration (p = 0.041), PPI + mucosal protective agent combination therapy (p = 0.039), and LDA + warfarin combination therapy (p < 0.001). Multivariate analysis of these factors yielded odds ratios of 1.04 for ESD duration, 14.83 for LDA + warfarin combination therapy, and 0.27 for PPI + mucosal protective agent combination therapy.ConclusionsThe risk of postoperative hemorrhage following gastric ESD was higher in patients with antithrombotic therapy than in those without that therapy. Among these patients, LDA + warfarin combination therapy and longer ESD duration were significant risk factors for postoperative bleeding. On the contrary, a mucosal protective agent to PPI therapy, lowering the odds ratio for postoperative bleeding, which suggests that the addition of a mucosal protective agent might be effective in preventing post-ESD hemorrhage in patients on antithrombotic therapy.

The novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019 (COVID-19) and the ensuing worldwide pandemic. The spread of the virus has had global effects such as activity restriction, economic stagnation, and collapse of healthcare infrastructure. Severe SARS-CoV-2 infection induces a cytokine storm, leading to acute respiratory distress syndrome (ARDS) and multiple organ failure, which are very serious health conditions and must be mitigated or resolved as soon as possible. Mesenchymal stem cells (MSCs) and their exosomes can affect immune cells by inducing anti-inflammatory macrophages, regulatory T and B cells, and regulatory dendritic cells, and can inactivate T cells. Hence, they are potential candidate agents for treatment of severe cases of COVID-19. In this review, we report the background of severe cases of COVID-19, basic aspects and mechanisms of action of MSCs and their exosomes, and discuss basic and clinical studies based on MSCs and exosomes for influenza-induced ARDS. Finally, we report the potential of MSC and exosome therapy in severe cases of COVID-19 in recently initiated or planned clinical trials of MSCs (33 trials) and exosomes (1 trial) registered in 13 countries on ClinicalTrials.gov.

Background and Aim: Endoscopic submucosal dissection (ESD) is reported to be a safe and reliable procedure for the elderly, but these reports could have already had a bias at the time ESD was performed. However, the reports have not clearly stated the criteria of indications. In the present study, we retrospectively elucidated the usefulness and problems of ESD for early gastric cancer in elderly patients (Ն 65 years) in comparison with non-elderly patients. Methods: The subjects were selected from 412 consecutive patients with early gastric cancer (515 lesions) for which ESD was performed between June 2002 and February 2010. The following were used for analysis between groups: pre-and postoperative performance status (PS) of subjects, prevalence rates of pre-existing comorbidities, characteristics of lesions, treatment outcomes, durations of hospitalization, operating times, incidence rates of complications and durations of hospitalization, and postoperative hemorrhage rates, and duration of hospitalization in patients with anticoagulant therapy. Results: Of the lesions in the elderly, four patients (1.0%) were elderly with a PS of 3. The PS increased to six patients (1.6%) after the procedure. None of the non-elderly had a PS of 3 before or after the procedure. The ratio of patients with a pre-existing comorbidity was higher in the elderly than in the non-elderly. There were no differences between the two groups in the characteristics of the lesions, their duration of hospitalization, their operating times, or the incidence rates of complications. However, the elderly with perforations had a significantly longer hospitalization than the comparable non-elderly. The percentage of the patients taking anticoagulant drugs was significantly higher among the elderly. Of the patients on anticoagulant therapy, the duration of hospitalization tended to be longer in the elderly but no significant difference was found. None of the non-elderly with postoperative hemorrhage had received anticoagulant therapy. In the elderly with postoperative hemorrhage, 15.8% of the lesions were in those who had received anticoagulant therapy, indicating a significantly higher percentage of such lesions in the elderly group. Conclusion: We conclude that ESD is useful in elderly patients because there is a similar risk as for the non-elderly if the approach is individualized, and the following are taken into consideration when making the final decision of performing ESD in an elderly patient: patients should have a PS of 0, 1, or 2; determine whether or not anticoagulant therapy can be discontinued and whether or not treatment can be performed reliably without complications.

Vonoprazan is as effective as lansoprazole in treating ESD-induced ulcers.