Comparative study of the efficacy of intra-arterial and intravenous transplantation of human induced pluripotent stem cells-derived neural progenitor cells in experimental stroke

Proposed Mechanisms of Cell Therapy for Alzheimer's Disease

Alzheimer's disease is a progressive neurodegenerative disorder characterized by mitochondria dysfunction, accumulation of beta-amyloid plaques, and hyperphosphorylated tau tangles in the brain leading to memory loss and cognitive deficits. There is currently no cure for this condition, but the potential of stem cells for the therapy of neurodegenerative pathologies is actively being researched. This review discusses preclinical and clinical studies that have used mouse models and human patients to investigate the use of novel types of stem cell treatment approaches. The findings provide valuable insights into the applications of stem cell-based therapies and include the use of neural, glial, mesenchymal, embryonic, and induced pluripotent stem cells. We cover current studies on stem cell replacement therapy where cells can functionally integrate into neural networks, replace damaged neurons, and strengthen impaired synaptic circuits in the brain. We address the paracrine action of stem cells acting via secreted factors to induce neuroregeneration and modify inflammatory responses. We focus on the neuroprotective functions of exosomes as well as their neurogenic and synaptogenic effects. We look into the shuttling of mitochondria through tunneling nanotubes that enables the transfer of healthy mitochondria by restoring the normal functioning of damaged cells, improving their metabolism, and reducing the level of apoptosis.

Safety and efficacy of allogenic human amniotic epithelial cells transplantation via ovarian artery in patients with premature ovarian failure: a single-arm, phase 1 clinical trial

Background

Premature ovarian failure (POF) is a prevalent and severe condition that impairs female health but there is currently no effective treatment available to restore ovarian function. Human amniotic epithelial cells (hAECs) exhibit ovarian protection in pre-clinical models. Thus, we conducted a single-arm, phase 1 clinical trial to assess the safety and efficacy of allogenic hAECs in treating POF.

Methods

A total of 35 patients received 6 × 107 hAECs via ovarian artery and completed a five-month follow-up from December 30, 2020 to January 31, 2022. The follow-up assessments were conducted at various intervals after hAECs treatment, including one month (Visit-1, V-1), three months (Visit-2, V-2), and five months (Visit-3, V-3) post-treatment. The primary endpoints were incidence of adverse events (AEs), and clinically significant laboratory abnormalities. Secondary endpoints included evaluation of transvaginal ultrasound results, sex hormone levels, Menopausal Quality of Life (MENQOL) questionnaire, as well as reproductive indicators. This trial was registered at www.clinicaltrials.gov as NCT02912104.

Findings

No serious AEs were observed throughout the five-month follow-up period. The most common AE was hematoma (7/35, 20.00%), and other AEs include pelvic pain (4/35, 11.43%), fever (2/35, 5.71%), anaphylaxis (2/35, 5.71%), and hepatotoxicity (1/35, 2.86%). After hAECs transplantation (hAECT), significant improvements were observed in the levels of endometrial thickness, left ovarian volume, sex hormones (follicle-stimulating hormone (FSH) and estradiol (E2)), and MENQOL scores in all patients during the five-month follow-up period. Among them, 13 participants (37.14%) experienced spontaneous menstrual bleeding, and 20.00% (7/35) reported more than one regular menstrual bleeding post-hAECT. In this response group, significant improvements were observed in endometrial thickness, left ovarian volume, levels of FSH, E2, anti-Müllerian hormone (AMH), and MENQOL scores one month after hAECT in comparison to pre-hAECT.

Interpretation

hAECT via ovarian artery is safe, well-tolerated and temporarily ameliorates endometrial thickness, ovarian size, hormone levels, and menopausal symptoms in POF patients. Further randomized controlled trial of hAECs with longer follow-up period and a larger sample size is warranted.

Funding

National Natural Science Foundation of China (No. 82271664), the Interdisciplinary Program of Shanghai Jiao Tong University (YG2022ZD028), the Shanghai Municipal Health Committee (202240345), Shanghai Key Laboratory of Embryo Original Diseases (No. Shelab2022ZD01), Shanghai Municipal Education Commission (No. 20152236), and National Key Research and Development Program of China (No. 2018YFC1004802), Shanghai Clinical Research Center for Cell Therapy, China (No. 23J41900100).

Revolutionizing Stroke Recovery: Unveiling the Promise of Stem Cell Therapy

Stem cells, renowned for their unique regenerative capabilities, present significant hope in treating stroke, a major cause of disability globally. This review offers a detailed analysis of stem cell applications in stroke (ischemic and hemorrhagic) recovery. It examines therapies based on autologous (patient-derived), allogeneic (donor-derived), and Granulocyte-Colony Stimulating Factor (G-CSF) based stem cells, focusing on cell types such as Mesenchymal Stem/Stromal Cells (MSCs), Bone Marrow Mononuclear Stem Cells (BMMSCs), and Neural Stem/Progenitor Cells (NSCs). The paper compiles clinical trial data to evaluate their effectiveness and safety and addresses the ethical concerns of these innovative treatments. By explaining the mechanisms of stem cell-induced neurological repair, this review underscores stem cells' potential in revolutionizing stroke rehabilitation and suggests avenues for future research.

Mesenchymal stem cells in the treatment of ischemic stroke

Over the past two decades, multiple preclinical studies have shown that transplantation of mesenchymal stem cells leads to a pronounced positive effect in animals with experimental stroke. Based on the promising results of preclinical studies, several clinical trials on the transplantation of mesenchymal stem cells to stroke patients have also been conducted. In this review, we present and analyze the results of completed clinical trials dedicated to the mesenchymal stem cells transplantation in patients with ischemic stroke. According to the obtained results, it can be concluded that transplantation of mesenchymal stem cells is safe and feasible from the economic and biomedical point of view. For the further implementa-tion of this promising approach into the clinical practice, randomized, placebo-controlled, multicenter clinical trials are needed with a large sample of patients and optimized cell transplantation protocols and patient inclusion criteria. In this review we also discuss possi-ble strategies to enhance the effectiveness of cell therapy with the use of mesenchymal stem cells.