Immunotherapy: ALLOGENEIC UMBILICAL CORD BLOOD REGULATORY T CELLS DECREASE INFLAMMATION AND PRESERVE ANTI-TUMOR ACTIVITY OF CAR T CELLS

Background & Aim: With larger accessibility and increased number of patients being treated with CART cell therapy, real-world toxicity continues to remain a significant challenge to its widespread adoption. We have previously shown that allogeneic umbilical cord blood derived (UCB) regulatory T cells (Tregs) can resolve uncontrolled inflammation and can treat acute and immune mediated lung injury in a xenogenic model as well as in patients suffering from COVID-19 acute respiratory distress syndrome. The unique properties of UCB Tregs including: i) lack of plasticity when exposed to inflammatory micro-environments;ii) no requirement for HLA matching;iii) long shelf life of cryopreserved Tregs;and iv) immediate product availability for on demand treatment, makes them an attractive source for treating acute inflammatory syndromes. Therefore, we hypothesized that add-on therapy with UCB derived Tregs may resolve uncontrolled inflammation responsible for CART cell therapy associated toxicity. Methods, Results & Conclusion(s): UCB Tregs were added in 1:1 ratio to CART cells, where no interference in their ability to kill CD19+ Raji cells, was detected at different ratios : 8:1 (80.4% vs. 81.5%);4:1 (62.0% vs. 66.2%);2:1 (50.1% vs. 54.7%);1:1 (35.4% vs. 44.1%) (Fig 1A). In a xenogenic B cell lymphoma model, multiple injections of Tregs were administered after CART injection (Fig 1B), which did not impact distribution of CD8+ T effector cells (Fig 1C) or CART cells cells (Fig 1D) in different organs. No decline in the CAR T levels was observed in the Tregs recipients (Fig 1E). Specifically, no difference in tumor burden was detected between the two arms (Fig 2A). No tumor was detected in CART+Tregs in liver (Fig 2B) or bone marrow (Fig 2C). A corresponding decrease in multiple inflammatory cytokines in peripheral blood was observed in CART+Tregs when compared to CART alone (Fig 2D). Here we show "proof of concept" for add-on therapy with Tregs to mitigate hyper-inflammatory state induced by CART cells without interference in their on-target anti-tumor activity. The timing of Tregs administration after CART cells have had sufficient time for forming synapse with tumor cells allows for preservation of their anti-tumor cytotoxicity, such that the infused Tregs home to the areas of tissue damage to bind to the resident antigen presenting cells which in turn collaborate with Tregs to resolve inflammation. Such differential distribution of cells allow for a Treg "cooling blanket" and lays ground for clinical study. [Figure presented]Copyright © 2023 International Society for Cell & Gene Therapy

Lipid nanoparticle library towards development next generation genomic medicines

Ionizable amino lipids are a major constituent of the lipid nanoparticles for delivering nucleic acid therapeutics (e.g., DLin-MC3-DMA in ONPATTRO , ALC-0315 in Comirnaty , SM-102 in Spikevax ). Scarcity of lipids that are suitable for cell therapy, vaccination, and gene therapies continue to be a problem in advancing many potential diagnostic/therapeutic/vaccine candidates to the clinic. Herein, we describe the development of novel ionizable lipids to be used as functional excipients for designing vehicles for nucleic acid therapeutics/vaccines in vivo or ex vivo use in cell therapy applications. We first studied the transfection efficiency (TE) of LNP-based mRNA formulations of these ionizable lipid candidates in primary human T cells and established a workflow for engineering of primary immune T cells. We then adapted this workflow towards bioengineering of CAR constructs to T cells towards non-viral CAR T therapy. Lipids were also tested in rodents for vaccine applications using self-amplifying RNA (saRNA) encoding various antigens. We have then evaluated various ionizable lipid candidates and their biodistribution along with the mRNA/DNA translation exploration using various LNP compositions. Further, using ionizable lipids from the library, we have shown gene editing of various targets in rodents. We believe that these studies will pave the path to the advancement in nucleic acid based therapeutics and vaccines, or cell gene therapy agents for early diagnosis and detection of cancer, and for targeted genomic medicines towards cancer treatment and diagnosis.

Immunotherapy: RAPID ACCESS TO VIRUS-SPECIFIC T CELLS FOR ADOPTIVE IMMUNOTHERAPY FOR COMPASSIONATE USE IN AUSTRALIA

Background & Aim: Adoptive T cell immunotherapy holds great promise for the treatment of viral complications. Our group has been developing and trialling virus-specific T cell therapies for more than 20 years. Recently, we have generated a repository of multi-virus-specific T cells for our clinical trials. Unfortunately, for many patients with viral complications, there is no suitable trial through which to access these therapies. In Australia, the Therapeutic Goods Administration has a Special Access Scheme (SAS) to enable provision of unapproved therapies for compassionate use. Our research group is now a leading Australian provider of "off-the-shelf" and custom-grown allogeneic virus-specific T cells to hospitals for patients with no other treatment options. Methods, Results & Conclusion(s): We have generated a repository of multi-virus-specific T cells from 20 healthy donors, with up to 150 doses of T cells per donor generated from a single blood sample. Each product batch is thoroughly characterised in terms of viral antigen specificity, HLA restriction and alloreactivity. These T cells target a combination of Epstein-Barr virus, cytomegalovirus, BK polyomavirus, John Cunningham virus and adenovirus epitopes. We have also generated a repository of SARS-CoV-2-specific T cells and occasionally grow custom patient-specific batches of T cells from nominated donors, on request. Since 2008, we have provided virus-specific T cells to 15 hospitals across Australia, and the volume of supply requests has significantly increased in recent years, as clinicians have gained interest in adoptive immunotherapy. In 2022, we provided T cells for 26 patients via the SAS. The majority were experiencing post-transplant complications, including cytomegalovirus disease, BK virus-associated haemorrhagic cystitis and post-transplant lymphoproliferative disorder. Through our clinical trials, we have developed rigorous processes for T cell therapy manufacture and characterisation, in addition to a computer-based selection algorithm, which we apply to SAS cases. As these cases are not part of a clinical trial, concomitant therapy varies, and monitoring is not uniform. However, we have received reports of clinical benefit from adoptive T cell therapy. These include cases of reduction in viral load, improvement in symptoms, and complete resolution of infection. We believe that these promising T cell therapies should be available to hospitals through a nationally funded centre for cellular therapies for critically ill patients.Copyright © 2023 International Society for Cell & Gene Therapy

Immunotherapy: SYNERGISTIC PERITONEAL ANTI-TUMOR EFFECT OF ALLOCETRAOTS, A CELLULAR IMMUNE-THERAPY, IN COMBINATION WITH IMMUNE CHECKPOINT INHIBITORS/CHEMOTHERAPY, THROUGH IN-VIVO REPROGRAMMING OF MACROPHAGES AND DENDRITIC CELLS

Background & Aim: Immune checkpoint inhibitors (ICI) revolutionized solid tumor treatment, however, in many tumors only partial response is achieved. Allocetra-OTS has an immune modulating effect on macrophages and dendritic cells and showed an excellent safety profile in patients including patients with sepsis and Covid-19. Here we investigated the anti-tumoral effect of Allocetra-OTS cellular therapy, in peritoneal solid tumor animal models. Methods, Results & Conclusion(s): Allocetra-OTS is manufactured from enriched mononuclear fractions and induced to undergo early apoptosis. Balb/c mice were inoculated intraperitoneally (IP) with AB12 (mesothelioma) with pLenti-PGK-V5-Luc-Neo and treated with anti- CTLA4 with or without Allocetra-OTS. Mice were monitored daily for clinical score and weekly using IVIS (Fig.1). Kaplan-Meier log rank test was done for survival. For Allocetra-OTS preparation, enriched mononuclear fractions were collected by leukapheresis from healthy eligible human donors and induced to undergo early apoptosis. Anti- CTLA4 standalone therapy significantly improved survival (Fig.2) from mean 34+/-9 to 44.9 +/-20 days. However, OTS standalone therapy was non-inferior and improved survival to 52.3 +/-20 days. Anti-CTLA4 + Allocetra-OTS combination therapy, ameliorated survival to 86.7+/-20 days with complete cancer remission in 60-100% of mice. Similar anti- tumoral effects of Allocetra-OTS were seen in mesothelioma model in a combination therapy with either anti-PD1 or cisplatin and using anti-PD1 in ID8 ovary cancer model. Based on single cell analysis confirmed by flow cytometry and pathology, the mechanism of action seems to be related or at least associated with an increase in f/480high peritoneal macrophages and a decrease in recruited macrophages, and to f/480high infiltration of the tumor. However, further studies are needed to confirm these observations. During IP tumor progression, Allocetra-OTS as a standalone therapy or in combination with ICI, or cisplatin, significantly reduced tumor size and resulted in complete remission in up to 100% treated mice. Similar results were obtained in ID8 ovary cancer. Based on excellent safety profile in > 50 patients treated in prior clinical trials for sepsis and Covid-19, Phase I/II clinical trial of Allocetra-OTS plus chemotherapy has started and three patient already recruited. A second phase I/II clinical trial of Allocetra- OTS plus anti-PD1, as a second- and third-line therapy in various cancers, was initiated in Q1 2023. [Figure presented]Copyright © 2023 International Society for Cell & Gene Therapy

Mesenchymal Stem/Stromal Cells: DEVELOPMENT OF A GMP BANKING PROCESS FOR UMBILICAL CORD MESENCHYMAL STROMAL CELLS (UC-MSCS) AND USE OF UC-MSC IN CHARACTERISATION ASSAYS, FUNCTIONAL ASSAYS AND GENE EDITING STUDIES

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

Immunotherapy: OFF-THE-SHELF PARTIAL HLA MATCHING SARS-COV-2 ANTIGEN SPECIFIC T CELL THERAPY FOR SEVERE COVID-19 PATIENTS

Background & Aim: Immunological characteristics of COVID-19 show pathological hyperinflammation associated with lymphopenia and dysfunctional T cell responses. These features provide a rationale for restoring functional T cell immunity in COVID-19 patients by adoptive transfer of SARS-CoV-2 specific T cells. Methods, Results & Conclusion(s): To generate SARS-CoV-2 specific T cells, we isolated peripheral blood mononuclear cells from 7 COVID-19 recovered and 13 unexposed donors. Consequently, we stimulated cells with SARS-CoV-2 peptide mixtures covering spike, membrane and nucleocapsid proteins. Then, we culture expanded cells with IL-2 for 21 days. We assessed immunophenotypes, cytokine profiles, antigen specificity of the final cell products. Our results show that SARSCoV- 2 specific T cells could be expanded in both COVID-19 recovered and unexposed groups. Immunophenotypes were similar in both groups showing CD4+ T cell dominance, but CD8+ and CD3+CD56+ T cells were also present. Antigen specificity was determined by ELISPOT, intracellular cytokine assay, and cytotoxicity assays. One out of 14 individuals who were previously unexposed to SARS-CoV-2 failed to show antigen specificity. Moreover, ex-vivo expanded SARS-CoV-2 specific T cells mainly consisted of central and effector memory subsets with reduced alloreactivity against HLA-unmatched cells suggesting the possibility for the development of third-party partial HLA-matching products. In conclusion, our findings show that SARSCoV- 2 specific T cell can be readily expanded from both COVID-19 and unexposed individuals and can therefore be manufactured as a biopharmaceutical product to treat severe COVID-19 patients.Copyright © 2023 International Society for Cell & Gene Therapy

Immunotherapy: ADOPTIVE T CELL IMMUNOTHERAPY FOR SARS-COV-2

Background & Aim: Despite the successful implementation of vaccines worldwide, COVID-19 remains a risk in patients with a compromised immune system. Emerging viral variants have also reduced the effectiveness of monoclonal antibody therapies in these patients. New treatment options are therefore required to improve clinical outcomes. Methods, Results & Conclusion(s): T cell immunotherapy has proven effective for the treatment of a number of refractory viral diseases in patients with a compromised immune system. We have now completed the manufacture of a bank of SARS-CoV-2 specific T cells and commenced an open-label phase I clinical trial at the Royal Brisbane and Women's Hospital, Australia. Patients enrolled in the study receive two doses of partially HLA-matched allogeneic T cells at a fortnightly interval. We have thus far recruited and treated three immune compromised patients with SARS-CoV-2 T cells. In two of the three patients treated thus far, the administration of T cell therapy was coincident with the clearance of viral load after 28 days. Viral clearance in these patients was also associated with an increase in circulating SARS-CoV-2 specific T cells. Our preliminary observations suggest that SARS-CoV-2 specific T cell therapy is well tolerated and has the potential to impact viral control in immune compromised patients.Copyright © 2023 International Society for Cell & Gene Therapy

Application of MSCs therapy in COVID-19

The year 2019 ended with the official report of an unknown pneumonia outbreak in Wuhan, Hubei Province, China. Subsequently, this novel pneumonia was named COVID-19, which mainly attacks the respiratory system, causing severe damage. Although vaccination has relieved the stress of combating pandemics around the world after one year, there are still unknowns and challenges that come with hope. In this regard, stem cell therapy has been proposed as an effective approach to treating COVID-19. Mesenchymal stem cells (MSCs) can potentially be used as a hopeful tool in the cell-based therapy due to their ability to regenerate and regulate immune response. Although research and clinical results have shown encouraging achievement in patients who were treated with MSCs, drawbacks and challenges still exist in the face of new opportunities. This review aims to introduce the challenges of the COVID-19 vaccine and the possible clinical use of MSC-based therapy. Through analysis of COVID-19 and MSC-based therapy, the author aims to find the possibilities and feasibility of using MSCs to treat acute respiratory diseases, such as COVID. As a result, the author finds that MSC treatment is very practical, and it shows significant potential to treat COVID-19. © 2023 SPIE.

Mesenchymal Stem/Stromal Cells: BIOLOGICAL THREAT AGENT RICIN INTOXICATION OF THE LUNGS IS EFFECTIVELY TREATED BY MESENCURE, A PROFESSIONALIZED ALLOGENEIC MESENCHYMAL CELL THERAPY, PREFERABLY VIA THE SUBCUTANEOUS ROUTE

Background & Aim: Ricin is one of the most lethal toxins, particularly if inhaled, and is considered a biological threat agent due to its wide availability and ease of production. Pulmonary ricin intoxication manifests in ARDS, cytokine storm, immune infiltration, and severe edema. Passive immunization is the preferred measure against pulmonary ricinosis, but only if administered shortly after exposure. Despite their potential to remedy pulmonary injury and inflammation, mesenchymal cell (MSC) therapies were never investigated in ricinosis. Here, we report the potential for treating pulmonary ricinosis with MesenCure, a professionalized allogeneic MSC therapy shown to reduce the mortality of patients suffering from severe pulmonary manifestations of COVID by 68%. Methods, Results & Conclusion(s): Preliminary studies demonstrated positive MesenCure effects in a sub-lethal pulmonary ricinosis model in CD1 mice. This model is regarded as highly translational due to the broad heterogeneity of these outbred mice. Positive effects included a reduction in excess protein content of the bronchoalveolar lavage fluid (BALF) by 45% when MesenCure was injected intravenously (IV) at 125k cells/animal, 48h post-exposure (PE) and evaluated one day later (p<0.05, Fig. 1A). Moreover, we found up to 52% reduction in the excess BALF leukocytes, when MesenCure was injected IV, 24h PE using the same dose (p<0.05, Fig. 1B) or 6h PE using a double dose (p<0.01, Fig. 1C), and evaluated two days PE. Optimizing the dose and administration route further improved the therapeutic outcome of MesenCure applied 6h PE as assessed by weight loss. As shown in Fig. 1D-E, IV injection of 250k-500k MesenCure cells/animal slightly protected the intoxicated animals against weight loss (p for treatment x time interaction <0.01 or <0.05 for 250k and 500k cells/animal, respectively). Interestingly, one million cells IV resulted in a lesser effect (not shown), however when injected subcutaneously (SC), 1M cells were very effective (p<0.001, Fig. 1F), seemingly even more effective than 2M cells/animal SC (Fig. 1G). Surprisingly, 2M thawed cells/animal injected SC protected the animals against weight loss almost completely (p<0.0001, Fig. H). In conclusion, we provide evidence for the potential of SC MSCs, specifically MesenCure, for treating pulmonary ricinosis and possibly other forms of ARDS. In agreement with Giri and Galipeau (2020), we provide further evidence for the dependency of MSC outcomes on their specific state and administration route. [Figure presented]Copyright © 2023 International Society for Cell & Gene Therapy

The Future of COVID-19: What Is Next in the Drug Pipeline

Objectives: Development of new and repurposed medicines in response to the COVID-19 pandemic has occurred at an unprecedented rate, resulting in a dynamic pipeline marked by significant challenges and successes. This analysis provides an overview of the vaccines and therapies undergoing clinical evaluation or with recent approval for the treatment and prevention of COVID-19 in global markets. Method(s): For this analysis, COVID-19 pipeline medicines are defined in three categories: vaccines, new treatments and repurposed medicines. GlobalData is the primary data source for this study, in addition to online databases from Health Canada, the US FDA, and the EMA. International markets examined include the US and geographic Europe (excluding Russia and Turkey). Result(s): As of November 2022, the global pipeline contained over 600 therapies and vaccines undergoing Phase I, II, III clinical trials or pre-registration for the prevention and treatment of COVID-19. Preventive and repurposed medicines include antivirals, immunoglobulins, monoclonal antibodies, cellular therapies, and convalescent plasma. In Canada, twelve medicines, including six vaccines, have been approved for COVID-19. The number of global approvals is greater, with approximately 9 vaccines on the market in OECD countries. In addition to pre-exposure preventative therapies, manufacturers are also developing COVID-19 drugs to be used as prophylactic therapy. The analysis identifies new oral antiviral treatments and preventative therapies in the pipeline and under review in various jurisdictions globally. Conclusion(s): This research provides a clearer picture of the characteristics and evolution of the market for new and emerging COVID-19 medicines, which will help policy-makers and other stakeholders understand and anticipate the unique pressures of the COVID-19 pandemic.Copyright © 2023

EXPERIENCE WITH TIXAGEVIMAB AND CILGAVIMAB (EVUSHELD) IN 86 RHEUMATIC PATIENTS UNDERGOING ANTI-B CELL THERAPY WITH RITUXIMAB.

The problem of prevention of coronavirus disease 2019 (COVID-19) in patients with immune-mediated inflammatory rheumatic diseases (IMRD) remains highly relevant. The presence of IRD is associated with a high risk of disease and severe course of COVID-19 during immunosuppressive treatment, primarily anti-B cell therapy with rituximab (RTX), and a low level of post-vaccination response in such patients. A new strategy for the prevention and treatment of COVID-19 are virus-neutralizing monoclonal antibodies to coronavirus;currently, combined long-acting monoclonal antibodies tixagevimab and cilgavimab (Evusheld) are registered for prevention in the world and the Russian Federation. . Tixagevimab and cilgavimab (TC) show neutralizing activity against SARS-CoV-2, including the Omicron strain, primarily its variants BA.4, BA.5, BA.2.75 ("Centaur"). Objective - to evaluate the efficacy and safety of TC for pre-exposure prophylaxis of COVID-19 in rheumatic patients receiving RTX, based on a prospective observational study. Materials and methods. The main group included 86 patients with various IMRD receiving RTX: 50 of them had ANCA-associated systemic vasculitis (AAV), 15 - rheumatoid arthritis, 9 - Sjogren's syndrome (SS), 4 - IgG4-related disease, 3 - systemic lupus erythematosus (SLE), 3 - dermatomyositis (DM), 2 - systemic scleroderma (SSD). Median age was 59 (19-82) years;male: female ratio - 1:1,8. From March 26 to August 30 2022, patients received a single intramuscular injection of TC in a total dose of 300 mg, mainly after RTX (in 52% of cases, in 28% on the next day after RTX). The control group included 42 patients with AAV (median age - 45 (35-71) years;male: female ratio - 1:1), also treated with RTX, who did not receive pre-exposure prophylaxis of TC. The duration of observation was 7 months, until November 1 2022. At this time, 98% of confirmed cases of coronavirus in the Russian Federation were Omicron. A telephone and/or online survey of patient has been conducted to detect cases of COVID-19 and adverse reactions. Results. In the TC group, confirmed coronavirus infection have been detected in 17 (20%) patients (AAV - 10, SS - 3, SSD - 2, SLE - 1, DM - 1), with fever in 7 (8%), only in one case hospitalization was required (lung damage was not detected in computed tomography), in two cases, according to CT mild lung damage (CT 1-2), there were no deaths. Good TC's tolerability was noted, signs not associated with COVID-19 or progression of IMRD after administration of TC were observed in 8 (9%) patients (GPA - 3 MPA - 1, RA - 2, SLE - 1, IgG4-related disease - 1), adverse reactions definitely associated with the use of TC were not found. The most serious event not associated with coronavirus infection was the progression of polyneuropathy in a patient with RA. In the control group, 3 (7%) patients were diagnosed with COVID-19, one with severe lung injury (CT 3, pulmonary embolism) and death. Conclusions. The data of clinical studies and our own clinical experience evidence the effectiveness of the use of a combination of long-acting monoclonal antibodies TC (Evusheld), registered for indications for pre-exposure prophylaxis and treatment of COVID-19. Patients with IMRD treated with RTX have a favorable safety profile of TC. The introduction of virus-neutralizing monoclonal antibodies, a new drug class for the prevention and treatment of infectious diseases, opens significant prospects for improving the prognosis of patients with IRD.Copyright © 2023 Ima-Press Publishing House. All rights reserved.

Immunotherapy: FAMILIAL CD45RA DEPLETED T CELLS TO TREAT SEVERE REFRACTORY INFECTIONS IN IMMUNOCOMPROMISED PATIENTS

Background & Aim: Immunocompromised patients are susceptible to high-risk opportunistic infections and malignant diseases. If available, most antiviral and antifungal drugs are quite toxic, relatively ineffective, and induce resistance in the long term. Methods, Results & Conclusion(s): We have previously demonstrated the safety of adoptive cell therapy for COVID-19 patients with CD45RA negative cells containing SARS-CoV-2-specific T cells from a donor, chosen based on HLA compatibility and cellular response to SARS-CoV-2 peptide pools. After finishing a Phase 2 randomized multicenter clinical trial (RELEASE, NCT04578210), we concluded that the infusion is safe, effective, accelerates lymphocyte recovery and shows hallmarks of an immune response. To use adoptive cell therapy to treat COVID-19 it would be necessary to develop a biobank of living drugs. For that, we examined the immune evolution performing a longitudinal analysis from previously SARS-CoV-2 infected and infection- naive individuals covering 21 months from infection. Cellular responses were maintained over time while humoral responses increased after vaccination but were gradually lost. Therefore, the best donors would be recovered individuals and two months after vaccination. We also evaluated the effect of dexamethasone (current standard of care treatment for COVID-19 and other infections involving lymphopenia) and Interleukin-15 (cytokine involved in T-cell maintenance and survival) on CD45RA negative. Dexamethasone did not alter cell functionality, proliferation or phenotype at a clinical-practice concentration, while interleukin-15 increased the memory T-cell and T-regulatory cell activation state, and interferon gamma release. Furthermore, we applied the adoptive passive transfer of CD45RA negative cells containing pathogen-specific memory T-cells to other infectious diseases characterized by sustained lymphopenia. We infused six immunocompromised patients with Cytomegalovirus, BK virus, Aspergillus, and Epstein-Barr virus lymphoproliferative disease. Patients experienced pathogen clearance, resolution of symptoms and lymphocyte increase. Transient microchimerism was detected in three patients. The use of CD45RA negative cells containing specific memory T cells of a third-party donor for treating severe pathogenic diseases in immunocompromised patients is feasible, safe, and effective, and has an advantage over other cell therapies such as lower costs and a less complex regulatory environment.Copyright © 2023 International Society for Cell & Gene Therapy

Pooled evidence from preclinical and clinical studies for stem cell-based therapy in ARDS and COVID-19.

COVID-19 has severely devastated many lives across the globe. It has been speculated that stem cell-based therapy for COVID-19 treatment could be able to subsidize the effects. In preclinical and clinical studies, stem cell-based therapy has successfully eliminated inflammatory cytokines in ALI, ARDS, and COVID-19. Clinical trials have produced a variety of promising results for validating stem cell therapy in COVID-19 patients. For instance, exosome-based therapy (ExoFlow) showed an 87% survival status, and MSC-based therapy (Mesoblast) achieved an 83% survival rate in moderate to severe COVID-19 patients. This review debates the advantages of cell-free therapy, i.e., stem cell-derived exosome-based therapies, over stem cell-based therapy. This review aims to question whether the immunomodulatory effect of stem cells differs based on their origin and also tries to find possible answers for the best stem cells for treating SARS-CoV-2 infection. The role of stem cells and their extracellular vesicles in the upregulation of regulatory immune cells, growth factors (EGF, FGF, VEGF), and anti-inflammatory cytokines (IL-6, INF-α, galectin-1, notch-1, PDL-1) that promote the tissue regeneration at the injured site. The right side of the image depicts the downregulation of inflammation-inducing immune cells, pro-inflammatory cytokines, and chemokines that could also enhance COVID-19 therapy.

The Art of Stem Cell-Based Therapy.

Potency assays represent crucial experiments at the hub of the comprehensive complexity surrounding cell therapy. Moreover, numerous factors beyond biological and scientific considerations are involved in achieving successful potency assays that fulfil regulatory authority approval for a new advanced therapy medicinal product. Though this can mean a frustratingly long period of discovery and development, progress in cell therapy is nowadays proceeding remarkably quickly, assisted by the potency assay rigorously placing emphasis on the need to critically analyse the key factor/s responsible for the therapeutic mechanism of action. History has shown that it can take many decades for there to be an improved understanding of a mechanism of action. Yet the chasing of precise targets has revolutionised medicine, with no clearer example than approaches to viral pandemics. The centuries involved in the eradication of smallpox have paved the way for an unprecedented pace of vaccine development for the Covid-19 pandemic. Such extraordinary accomplishments foster encouragement that similarly for stem cell-based therapy, our scientific knowledge will continue to improve apace. This chapter focuses on the art of experimentation and discovery, introducing potency assay requisites and numerous factors that can influence potency assay outcomes. A comprehensive understanding of potency assays and their development can hasten the provision of new cell therapies to help resolve burdensome diseases of unmet medical need.

Virus-Specific T Cells From Cryopreserved Blood During an Emergent Virus Outbreak for a Potential Off-the-Shelf Therapy.

During the first outbreak of an emergent virus, methods need to be developed to rapidly establish suitable therapies for patients with high risk of severe disease caused by the pathogen. Considering the importance of the T-cell response in controlling viral infections, adoptive cell therapy with virus-specific T cells has been used as a safe and effective antiviral prophylaxis and treatment for immunocompromised patients. The main objective of this study was to establish an effective and safe method to cryostore whole blood as starting material and to adapt a T-cell activation and expansion protocol to generate an off-the-shelf antiviral therapeutic option. Additionally, we studied how memory T-cell phenotype, clonality based on T-cell receptor, and antigen specificity could condition characteristics of the final expanded T-cell product. Twenty-nine healthy blood donors were selected from a database of convalescent plasma donors with a confirmed history of SARS-CoV-2 infection. Blood was processed using a fully automated, clinical-grade, and 2-step closed system. Eight cryopreserved bags were advanced to the second phase of the protocol to obtain purified mononucleated cells. We adapted the T-cell activation and expansion protocol, without specialized antigen-presenting cells or presenting molecular structures, in a G-Rex culture system with IL-2, IL-7, and IL-15 cytokine stimulation. The adapted protocol successfully activated and expanded virus-specific T cells to generate a T-cell therapeutic product. We observed no major impact of post-symptom onset time of donation on the initial memory T-cell phenotype or clonotypes resulting in minor differences in the final expanded T-cell product. We showed that antigen competition in the expansion of T-cell clones affected the T-cell clonality based on the T-cell receptor ß repertoire. We demonstrated that good manufacturing practice of blood preprocessing and cryopreserving is a successful procedure to obtain an initial cell source able to activate and expand without a specialized antigen-presenting agent. Our 2-step blood processing allowed recruitment of the cell donors independently of the expansion cell protocol timing, facilitating donor, staff, and facility needs. Moreover, the resulting virus-specific T cells could be also banked for further use, notably maintaining viability and antigen specificity after cryopreservation.

The power of telemedicine to improve CAR-T cell therapy programs: lessons learned from COVID-19 pandemic.

PURPOSE: CAR-T programs will burden increasingly on healthcare systems, since the implementation of these therapies involves: multidisciplinary team collaboration, post-infusion hospitalization with risk of life-threatening toxicities, frequent in hospital visits and prolonged follow-up which heavily influence patients' quality of life. In this review we propose an innovative, telehealth-based, model for monitoring CAR-T patients: this method was used for managing a case of COVID-19 infection occurred two weeks after CAR-T cell infusion. METHODS: Several benefits for management of all these aspects of CAR-T programs could be made using telemedicine: for example, telemedicine real-time clinical monitoring could reduce the COVID-19 contagion risks for CAR-T patients. RESULTS: Our experience confirmed feasibility and utility of this approach in a real-life case. We believe that use of telemedicine for CAR-T patients could improve: the logistics of toxicity monitoring (frequent vital sign checks and neurologic assessments), the multidisciplinary team communication (patient selection, specialists consulting, coordination with pharmacists, etc.), the decrease in hospitalization time and the reduction of ambulatory visits. CONCLUSIONS: This approach will be fundamental for future CAR-T cell program development, enhancing patients' quality of life and cost-effectiveness for healthcare systems.

Treatment of diseases through stem cell bioengineering techniques

The development of stem cell transplantation technology has opened up the possibility of curing many diseases that were difficult to treat in the past. There are ethical issues in the field of widespread clinical use of human embryonic stem cells, and tissue rejection may also occurs after transplantation. One way to solve these problems is to generate specific pluripotent stem cells directly from patient cells to study specific treatments. Induced stem cells refer to a type of cell produced by the reprogramming of human somatic cells into exogenous transcription factors, which are very similar to embryonic stem cells. Both types of cells express human pluripotent factors and embryonic stem cell surface markers, and have the potential to differentiate into 3 germ layers.The induced pluripotent stem cells can be induced to differentiate into different cells under different conditions. At present, stem cell therapy has entered the clinical trial stage in many fields, and this paper discusses the stem cell regenerative medicine in the field of cardiovascular disease, eye disease, and COVID-19. This paper is a review of the current status of stem cell treatment and the challenges it is facing. © 2023 SPIE.

Cell Therapy: cGMP Facilities and Manufacturing: Second Edition

This new edition presents a fully-updated and expanded look at current Good Manufacturing Practice (cGMP) for cell therapy products. It provides a complete discussion of facility design and operation including details specific to cord blood banking, cell processing, vector production and qualification of a new facility. Several chapters cover facility infrastructure including cleaning and maintenance, vendor qualification, writing a Standard Operating Procedure, staff training, and process validation. The detailed and invaluable product information covers topics like labelling, release and administration, transportation and shipment, et al. Further chapters cover relevant topics like writing and maintaining investigational new drug applications, support opportunities in North America and the European Union, commercial cell processing and quality testing services, and financial considerations for academic GMP facilities. A chapter on future directions rounds out Cell Therapy: cGMP Facilities and Manufacturing making it essential reading for any cell therapy professional involved in the development, use, or management of this type of facility. © Springer Nature Switzerland AG 2009, 2022, Corrected Publication 2022.