ABSTRACT
Background & Aim: The pro-angiogenic, immunoregulatory and anti- inflammatory properties of MSCs are being exploited for the development of cellular therapies, including the treatment of graft versus host disease (GvHD), inflammatory bowel disease and COVID-19. SNBTS have developed a GMP process to bank umbilical cord MSCs (UC-MSCs) whereby we can reliably bank 100 vials of 10 million P2 UC-MSCs per cord. Each of these vials can be extensively expanded and stored for specific applications. The ultimate aim of the bank is for off-the-shelf clinical use, e.g., in GvHD or as an adjuvant therapy in Islet transplantations. Methods, Results & Conclusion(s): During process development, different basal media and supplements were screened for proliferation and MSC marker expression. Cells grown in promising media combinations were then tested for tri-lineage differentiation (identity), their chemokine/cytokine expression and T-cell inhibition (function) assessed. Medium selected for further GMP development and scale up was ultimately determined by all round performance and regulatory compliance. GMP-like UC-MSCs were shown to have immune-modulatory activity in T-cell proliferation assays at 4:1 or 16:1 ratios. Co-culture of UC-MSCs and freshly isolated leukocytes, +/- the immune activating agent LPS, show a dose dependent survival effect on leukocytes. In particular, neutrophils, which are normally very short lived in vitro demonstrated increased viability when co-cultured with UCMSCs. The survival effect was partially reproduced when UC-MSC were replaced with conditioned medium or cell lysate indicating the involvement of soluble factors. This improved neutrophil survival also correlates with results from leukocyte migration studies that demonstrate neutrophils to be the main cell type attracted to MSCs in in vitro and in vivo. Genetic modification of UC-MSC may improve their therapeutic potential. We have tested gene editing by CRISPR/Cas9 technology in primary UC-MSCS. The CXCL8 gene, highly expressed in UC-MSC, was targeted in isolates from several different donors with editing efficiencies of 78-96% observed. This translated to significant knockdown of CXCL8 protein levels in resting cells, however after stimulation levels of CXCL8 were found to be very similar in edited and non-edited UC-MSCs. This observation requires further study, but overall the results show the potential to generate future banks of primary UC-MSCS with genetically enhanced pro-angiogenic, immunoregulatory and/or anti-inflammatory activities.Copyright © 2023 International Society for Cell & Gene Therapy
ABSTRACT
The coronavirus infection (COVID-19), an acute viral disease with predominant affection of the upper respiratory tract, is a challenge for modern medicine. Considering the fact that in the patho-genesis of coronavirus pneumonia there is violation of the im-mune response (hyper-response, cytokine storm) the drugs that locally regulate it may be promising in the pneumonia treatment. Biological activity of exosomes is widely investigated in the world. Small extracellular vesicles of mesenchymal cells have the following effects: anti-apoptotic, proliferation stimulation, anti-inflammatory and immunomodulatory. Objective(s): to evaluate the safety and efficacy of the method of inhalation administration of small extracellular vesicles in bilateral pneumonia caused by a new SARS-CoV-2 coronavirus infection. To study these effects an interventional, prospective, random-ized, double-blind, placebo-controlled study has been conducted to evaluate the safety and efficacy of inhaled small extracellular vesicles administration to the patients with bilateral pneumonia caused by the new coronavirus infection SARS-CoV-2. Altogether 36 patients with confirmed new coronavirus infection COVID-19, complicated by bilateral pneumonia of moderate severity (12 patients each in study groups 1 and 2, depending on the type of given small extracellular vesicles, and the control group) participated in the study. Small extracellular vesicles were inhaled twice a day in the dose of 2-10x1010 particles. The efficacy and safety of the method were assessed judging by the patients' general state, as-sessment of the disease severity, general and biochemical blood tests, coagulogram, saturation, CT scan of the lungs before and after 10 days of treatment. The observation period was 30 days after hospitalization. During the study the safety of the method was proved, all the patients recovered. Reliable differences of the blood CRP index, which normalized by day 10 of treatment in groups 1 and 2, but remained elevated in the control group. No significant differences were found in other assessed parameters.Copyright © 2022, Human Stem Cell Institute. All rights reserved.
ABSTRACT
The coronavirus infection (COVID-19), an acute viral disease with predominant affection of the upper respiratory tract, is a challenge for modern medicine. Considering the fact that in the patho-genesis of coronavirus pneumonia there is violation of the im-mune response (hyper-response, cytokine storm) the drugs that locally regulate it may be promising in the pneumonia treatment. Biological activity of exosomes is widely investigated in the world. Small extracellular vesicles of mesenchymal cells have the following effects: anti-apoptotic, proliferation stimulation, anti-inflammatory and immunomodulatory. Objective(s): to evaluate the safety and efficacy of the method of inhalation administration of small extracellular vesicles in bilateral pneumonia caused by a new SARS-CoV-2 coronavirus infection. To study these effects an interventional, prospective, random-ized, double-blind, placebo-controlled study has been conducted to evaluate the safety and efficacy of inhaled small extracellular vesicles administration to the patients with bilateral pneumonia caused by the new coronavirus infection SARS-CoV-2. Altogether 36 patients with confirmed new coronavirus infection COVID-19, complicated by bilateral pneumonia of moderate severity (12 patients each in study groups 1 and 2, depending on the type of given small extracellular vesicles, and the control group) participated in the study. Small extracellular vesicles were inhaled twice a day in the dose of 2-10x1010 particles. The efficacy and safety of the method were assessed judging by the patients' general state, as-sessment of the disease severity, general and biochemical blood tests, coagulogram, saturation, CT scan of the lungs before and after 10 days of treatment. The observation period was 30 days after hospitalization. During the study the safety of the method was proved, all the patients recovered. Reliable differences of the blood CRP index, which normalized by day 10 of treatment in groups 1 and 2, but remained elevated in the control group. No significant differences were found in other assessed parameters. Copyright © 2022, Human Stem Cell Institute. All rights reserved.
ABSTRACT
Mesenchymal stromal cells (MSC) are widely investigated for treating ARDS in Covid-19. Nonetheless, these efforts are overshadowed by studies predating the pandemic that mostly failed to show MSC efficacy in ARDS and recent disappointments with repurposed MSC products. Relying on years of MSC-related experience, Bonus BioGroup developed MesenCure: An enhanced allogeneic MSC therapy for Covid-19, professionalized by a unique combination of culture conditions and optimized in ARDS-relevant models. MesenCure is currently evaluated in a Phase II study in severe Covid-19 patients and administered (IV) in three doses (1.5M cells/kg, d1, d3, d5). A Phase I/II study on ten severe patients demonstrated a significant improvement in ARDS-related parameters following MesenCure treatment. Patients were discharged within one day (median) following treatment, requiring no respiratory support. Speedy recovery from local inflammation was observed in these patients, demonstrated by a rapid reduction in diffuse lung pneumonia, from 55% of the lung area to 15% within 5-6 days from the first dose (p<0.01, Fig. A-C). A corresponding drop in CRP was detected (p<0.01), which returned to normal. A multivariate regression analysis revealed that the reduction in CRP was mainly associated with the number of doses administered and not and the time elapsed since the first dose. MesenCure efficacy may be attributable to the cells' de novo expression of the gene encoding for the IL-6 receptor, making them more responsive to inflammation than non-professionalized naïve MSC (NA-MSC);as well as >8-fold upregulation of the EDIL3 gene, encoding for an endogenous inhibitor of immune infiltration. A corresponding immunosuppressive effect of MesenCure MSCs was demonstrated in vitro, showing their ability to suppress T cells activation twice more effectively than NA-MSC. In this study, MesenCure inhibited the proliferation of primary CD4 T cells in a concentration-depended manner following non-specific activation. Over 98% inhibition was achieved in co-culture of 1:10 MSC-to-PBMC with an IC 50 of 6k MSC/200k PBMCs (r 2=1.00) compared to 12k NA-MSC/200k PBMCs (r 2=0.95). Comparable results were also obtained for CD8 T cells. Similarly, MesenCure inhibited ROS production by primary neutrophils remarkably fast and by up to 80% within less than 40 minutes following their activation (IC 50 = 19k MSC/200k neutrophils, r 2=1.00). In addition to local immunosuppressive outcomes, a significant increase in blood leukocytes was observed in patients treated with MesenCure (p<0.05, Fig. D-F). Further analysis suggested that the increase in total WBCs and neutrophils was associated with the number of MesenCure doses administered (p<0.05, Fig. G-H). In contrast, the increase in lymphocytes was time-dependent (R=0.72, Fig. I). The seemingly exclusively localized anti-inflammatory effects seen in severe patients treated with MesenCure were also observed in animal (murine) studies. An in vivo study in an acute lung injury model demonstrated a dose-dependent localized reduction in leukocyte counts in the lung fluids of animals treated with MesenCure (IV) using two dose levels. Relative to untreated animals, MesenCure reduced lung leukocyte counts by 35%-43% in animals treated with the low dose and by 62%-67% following high-dose MesenCure treatment (p<0.05). The leukocytes' clearance from the lungs was accompanied by a 41%-57% reduction in lung edema (p<0.05) following MesenCure treatment. Notably, NA-MSC did not achieve the same effect. Similar to our clinical findings, a significant increase was measured in neutrophil counts in animals treated with low-dose MesenCure (p<0.05), which decreased dramatically (p< 0.01) in animals treated with a four-times higher dose. MesenCure is administered at a much lower dose compared to other MSC products administered at up to 10M cells/kg. Considering the increase in blood leukocytes measured in patients treated with low-dose MesenCure and comparable preclinical findings, our data suggest that low-dose MesenCure could elicit a potent ocal anti-inflammatory effect without suppressing, and even enhancing, peripheral immunity that is needed to fight the virus. Further research is inevitably required into the mechanism behind this phenomenon. However, our results indicate MesenCure's potential in relieving local inflammation while giving the patient a fighting chance against viremia. [Formula presented] Disclosures: Bronshtein: Bonus BioGroup: Current Employment. Ben David: Bonus BioGroup: Current Employment. Novak: Bonus BioGroup: Current Employment. Kivity: Bonus BioGroup: Current Employment. Meretzki: Bonus BioGroup: Current Employment. Rozen: Bonus BioGroup: Consultancy.