A phase I/II dose-escalation multi-center study to evaluate the safety of infusion of natural killer cells or memory T cells as adoptive therapy in coronavirus pneumonia and/or lymphopenia: RELEASE study protocol.

BACKGROUND: Moderate/severe cases of COVID-19 present a dysregulated immune system with T cell lymphopenia and a hyper-inflammatory state. This is a study protocol of an open-label, multi-center, double-arm, randomized, dose-finding phase I/II clinical trial to evaluate the safety, tolerability, alloreactivity, and efficacy of the administration of allogeneic memory T cells and natural killer (NK) cells in COVID-19 patients with lymphopenia and/or pneumonia. The aim of the study is to determine the safety and the efficacy of the recommended phase 2 dose (RP2D) of this treatment for patients with moderate/severe COVID-19. METHODS: In the phase I trial, 18 patients with COVID-19-related pneumonia and/or lymphopenia with no oxygen requirement or with an oxygen need of ≤ 2.5 liters per minute (lpm) in nasal cannula will be assigned to two arms, based on the biology of the donor and the patient. Treatment of arm A consists of the administration of escalating doses of memory T cells, plus standard of care (SoC). Treatment of arm B consists of the administration of escalating doses of NK cells, plus SoC. In the phase II trial, a total of 182 patients with COVID-19-related pneumonia and/or lymphopenia requiring or not oxygen supplementation but without mechanical ventilation will be allocated to arm A or B, considering HLA typing. Within each arm, they will be randomized in a 1:1 ratio. In arm A, patients will receive SoC or RP2D for memory T cells plus the SoC. In arm B, patients will receive SoC or RP2D for NK cells plus the SoC. DISCUSSION: We hypothesized that SARS-CoV-2-specific memory T-lymphocytes obtained from convalescent donors recovered from COVID-19 can be used as a passive cell immunotherapy to treat pneumonia and lymphopenia in moderate/severe patients. The lymphopenia induced by COVID-19 constitutes a therapeutic window that may facilitate donor engraftment and viral protection until recovery. TRIAL REGISTRATION: ClinicalTrials.gov NCT04578210 . First Posted : October 8, 2020.

Phase I dose-escalation single centre clinical trial to evaluate the safety of infusion of memory T cells as adoptive therapy in COVID-19 (RELEASE).

BACKGROUND: Effective treatments are still needed to reduce the severity of symptoms, time of hospitalization, and mortality of COVID-19. SARS-CoV-2 specific memory T-lymphocytes obtained from convalescent donors recovered can be used as passive cell immunotherapy. METHODS: Between September and November 2020 a phase 1, dose-escalation, single centre clinical trial was conducted to evaluate the safety and feasibility of the infusion of CD45RA- memory T cells containing SARS-CoV-2 specific T cells as adoptive cell therapy against moderate/severe cases of COVID-19. Nine participants with pneumonia and/or lymphopenia and with at least one human leukocyte antigen (HLA) match with the donor were infused. The first three subjects received the lowest dose (1 × 105 cells/kg), the next three received the intermediate dose (5 × 105 cells/kg) and the last three received the highest dose (1 × 106 cells/kg) of CD45RA- memory T cells. Clinicaltrials.gov registration: NCT04578210. FINDINGS: All participants' clinical status measured by National Early Warning Score (NEWS) and 7-category point ordinal scales showed improvement six days after infusion. No serious adverse events were reported. Inflammatory parameters were stabilised post-infusion and the participants showed lymphocyte recovery two weeks after the procedure. Donor microchimerism was observed at least for three weeks after infusion in all patients. INTERPRETATION: This study provides preliminary evidence supporting the idea that treatment of COVID-19 patients with moderate/severe symptoms using convalescent CD45RA- memory T cells is feasible and safe. FUNDING: Clinical Trial supported by Spanish Clinical Research Network PT17/0017/0013. Co-funded by European Regional Development Fund/European Social Fund. CRIS CANCER Foundation Grant to AP-M and Agencia Valenciana de Innovación Grant AVI-GVA COVID-19-68 to BS.

SARS-CoV-2-Specific Memory T Lymphocytes From COVID-19 Convalescent Donors: Identification, Biobanking, and Large-Scale Production for Adoptive Cell Therapy.

Syndrome coronavirus 2 (SARS-CoV-2) pandemic is causing a second outbreak significantly delaying the hope for the virus' complete eradication. In the absence of effective vaccines, we need effective treatments with low adverse effects that can treat hospitalized patients with COVID-19 disease. In this study, we determined the existence of SARS-CoV-2-specific T cells within CD45RA- memory T cells in the blood of convalescent donors. Memory T cells can respond quickly to infection and provide long-term immune protection to reduce the severity of COVID-19 symptoms. Also, CD45RA- memory T cells confer protection from other pathogens encountered by the donors throughout their life. It is of vital importance to resolve other secondary infections that usually develop in patients hospitalized with COVID-19. We found SARS-CoV-2-specific memory T cells in all of the CD45RA- subsets (CD3+, CD4+, and CD8+) and in the central memory and effector memory subpopulations. The procedure for obtaining these cells is feasible, easy to implement for small-scale manufacture, quick and cost-effective, involves minimal manipulation, and has no GMP requirements. This biobank of specific SARS-CoV-2 memory T cells would be immediately available "off-the-shelf" to treat moderate/severe cases of COVID-19, thereby increasing the therapeutic options available for these patients.

Generation, establishment and characterization of a pluripotent stem cell line (CVTTHi001-A) from primary fibroblasts isolated from a patient with activated PI3 kinase delta syndrome (APDS2).

APDS2 is caused by mutations in PIK3R1 gene resulting in constitutive PI3Kδ activation. PI3Kδ is predominantly expressed in leukocytes and plays critical roles in regulating immune responses. Here we first derived fibroblast primary cells from a skin biopsy of a patient carrying a heterozygous single T deletion in intron 11 of the PIK3R1 gene. We next present the derivation of an induced pluripotent stem cell (iPS) line using a non-integrative reprogramming technology. Pluripotent-related hallmarks are further shown, including: iPSCs self-renewal and expression of pluripotent and differentiation markers after in vitro differentiation towards embryonic germ layers, assessed by RT-PCR and immunofluorescence.

Treating primary immunodeficiencies with defects in NK cells: from stem cell therapy to gene editing.

Primary immunodeficiency diseases (PIDs) are rare diseases that are characterized by genetic mutations that damage immunological function, defense, or both. Some of these rare diseases are caused by aberrations in the normal development of natural killer cells (NKs) or affect their lytic synapse. The pathogenesis of these types of diseases as well as the processes underlying target recognition by human NK cells is not well understood. Utilizing induced pluripotent stem cells (iPSCs) will aid in the study of human disorders, especially in the PIDs with defects in NK cells for PID disease modeling. This, together with genome editing technology, makes it possible for us to facilitate the discovery of future therapeutics and/or cell therapy treatments for these patients, because, to date, the only curative treatment available in the most severe cases is hematopoietic stem cell transplantation (HSCT). Recent progress in gene editing technology using CRISPR/Cas9 has significantly increased our capability to precisely modify target sites in the human genome. Among the many tools available for us to study human PIDs, disease- and patient-specific iPSCs together with gene editing offer unique and exceptional methodologies to gain deeper and more thorough understanding of these diseases as well as develop possible alternative treatment strategies. In this review, we will discuss some immunodeficiency disorders affecting NK cell function, such as classical NK deficiencies (CNKD), functional NK deficiencies (FNKD), and PIDs with involving NK cells as well as strategies to model and correct these diseases for further study and possible avenues for future therapies.

Adult peripheral blood and umbilical cord blood NK cells are good sources for effective CAR therapy against CD19 positive leukemic cells.

Among hematological cancers, Acute Lymphoblastic Leukemia (ALL) and Chronic Lymphocytic Leukemia (CLL) are the most common leukemia in children and elderly people respectively. Some patients do not respond to chemotherapy treatments and it is necessary to complement it with immunotherapy-based treatments such as chimeric antigen receptor (CAR) therapy, which is one of the newest and more effective treatments against these cancers and B-cell lymphoma. Although complete remission results are promising, CAR T cell therapy presents still some risks for the patients, including cytokine release syndrome (CRS) and neurotoxicity. We proposed a different immune cell source for CAR therapy that might prevent these side effects while efficiently targeting malignant cells. NK cells from different sources are a promising vehicle for CAR therapy, as they do not cause graft versus host disease (GvHD) in allogenic therapies and they are prompt to attack cancer cells without prior sensitization. We studied the efficacy of NK cells from adult peripheral blood (AB) and umbilical cord blood (CB) against different target cells in order to determine the best source for CAR therapy. AB CAR-NK cells are slightly better at killing CD19 presenting target cells and CB NK cells are easier to stimulate and they have more stable number from donor to donor. We conclude that CAR-NK cells from both sources have their advantages to be an alternative and safer candidate for CAR therapy.

Two decades of embryonic stem cells: a historical overview.

STUDY QUESTION: How did the field of stem cell research develop in the years following the derivation of the first human embryonic stem cell (hESC) line? SUMMARY ANSWER: Supported by the increasing number of clinical trials to date, significant technological advances in the past two decades have brought us ever closer to clinical therapies derived from pluripotent cells. WHAT IS KNOWN ALREADY: Since their discovery 20 years ago, the use of human pluripotent stem cells has progressed tremendously from bench to bedside. Here, we provide a concise review of the main keystones of this journey and focus on ongoing clinical trials, while indicating the most relevant future research directions. STUDY DESIGN SIZE DURATION: This is a historical narrative, including relevant publications in the field of pluripotent stem cells (PSC) derivation and differentiation, recounted both through scholarly research of published evidence and interviews of six pioneers who participated in some of the most relevant discoveries in the field. PARTICIPANTS/MATERIALS SETTING METHODS: The authors all contributed by researching the literature and agreed upon body of works. Portions of the interviews of the field pioneers have been integrated into the review and have also been included in full for advanced reader interest. MAIN RESULTS AND THE ROLE OF CHANCE: The stem cell field is ever expanding. We find that in the 20 years since the derivation of the first hESC lines, several relevant developments have shaped the pluripotent cell field, from the discovery of different states of pluripotency, the derivation of induced PSC, the refinement of differentiation protocols with several clinical trials underway, as well as the recent development of organoids. The challenge for the years to come will be to validate and refine PSCs for clinical use, from the production of highly defined cell populations in clinical grade conditions to the possibility of creating replacement organoids for functional, if not anatomical, function restoration. LIMITATIONS REASONS FOR CAUTION: This is a non-systematic review of current literature. Some references may have escaped the experts' analysis due to the exceedingly diverse nature of the field. As the field of regenerative medicine is rapidly advancing, some of the most recent developments may have not been captured entirely. WIDER IMPLICATIONS OF THE FINDINGS: The multi-disciplinary nature and tremendous potential of the stem cell field has important implications for basic as well as translational research. Recounting these activities will serve to provide an in-depth overview of the field, fostering a further understanding of human stem cell and developmental biology. The comprehensive overview of clinical trials and expert opinions included in this narrative may serve as a valuable scientific resource, supporting future efforts in translational approaches. STUDY FUNDING/COMPETING INTERESTS: ESHRE provided funding for the authors' on-site meeting and discussion during the preparation of this manuscript. S.M.C.S.L. is funded by the European Research Council Consolidator (ERC-CoG-725722-OVOGROWTH). M.P. is supported by the Special Research Fund, Bijzonder Onderzoeksfonds (BOF01D08114). M.G. is supported by the Methusalem grant of Vrije Universiteit Brussel, in the name of Prof. Karen Sermon and by Innovation by Science and Technology in Flanders (IWT, Project Number: 150042). A.V. and B.A. are supported by the Plataforma de Proteomica, Genotipado y Líneas Celulares (PT1770019/0015) (PRB3), Instituto de Salud Carlos III. Research grant to B.H. by the Research Foundation-Flanders (FWO) (FWO.KAN.2016.0005.01 and FWO.Project G051516N). There are no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: Not applicable.ESHRE Pages are not externally peer reviewed. This article has been approved by the Executive Committee of ESHRE.

Genomic full-length sequence of two new HLA-C alleles, HLA-C*04:239 and HLA-C*05:137.

Two novel HLA-C alleles, C*04:239 and C*05:137, were characterized in Spanish individuals.

Characterization of the Epigenetic Changes During Human Gonadal Primordial Germ Cells Reprogramming.

Epigenetic reprogramming is a central process during mammalian germline development. Genome-wide DNA demethylation in primordial germ cells (PGCs) is a prerequisite for the erasure of epigenetic memory, preventing the transmission of epimutations to the next generation. Apart from DNA demethylation, germline reprogramming has been shown to entail reprogramming of histone marks and chromatin remodelling. Contrary to other animal models, there is limited information about the epigenetic dynamics during early germ cell development in humans. Here, we provide further characterization of the epigenetic configuration of the early human gonadal PGCs. We show that early gonadal human PGCs are DNA hypomethylated and their chromatin is characterized by low H3K9me2 and high H3K27me3 marks. Similarly to previous observations in mice, human gonadal PGCs undergo dynamic chromatin changes concomitant with the erasure of genomic imprints. Interestingly, and contrary to mouse early germ cells, expression of BLIMP1/PRDM1 persists in through all gestational stages in human gonadal PGCs and is associated with nuclear lysine-specific demethylase-1. Our work provides important additional information regarding the chromatin changes associated with human PGCs development between 6 and 13 weeks of gestation in male and female gonads. Stem Cells 2016;34:2418-2428.

Optimization of the management of platelet concentrate stocks in the Basque Country using mathematical simulation.

BACKGROUND AND OBJECTIVES: The management of platelet concentrate (PC) stocks is not simple given their short shelf life and variable demand. In general, managers decide on PC production based on personal experience. The objective of this study was to provide a tool to help decide how many PC units to produce each day in a more rational and objective way. MATERIALS AND METHODS: From the historical data on PCs produced, transfused and discarded in the Basque Country in 2012, a mathematical model was built, based on the normality of the time series of the transfusions performed on each day of the week throughout the year. This model was implemented in an easy-to-use Excel spreadsheet and validated using real production data from 2013. RESULTS: Comparing with real 2013 data, in the best scenario, the number of PC units that expired was 87·7% lower, PC production, 14·3% lower and the age of the PCs transfused nearly 1-day younger in the simulation. If we want to ensure a minimum stock at the end of each day, the outdating rate and average age of the transfused PCs progressively increase. CONCLUSION: The practical application of the designed tool can facilitate decision-making about how many PC units to produce each day, resulting in very significant reductions in PC production and wastage and corresponding cost savings, together with an almost 1 day decrease in the mean age of PCs transfused.

Genomic sequence of HLA-B*41:43, a new HLA-B allele generated by an intralocus recombination mechanism.

HLA-B*41:43 has been generated by an intralocus recombination comprising B*41:02:01 and a B*14, 38, or 67 allele.

The new HLA-A*24:321 shows one conservative amino acid replacement compared with HLA-A*24:02:01.

HLA-A*24:321 shows one nucleotide difference at codon 49 (GCG>GTG; A49>V49) compared with A*24:02:01.

Stem cells in reproductive medicine: ready for the patient?

STUDY QUESTION: Are there effective and clinically validated stem cell-based therapies for reproductive diseases? SUMMARY ANSWER: At the moment, clinically validated stem cell treatments for reproductive diseases and alterations are not available. WHAT IS KNOWN ALREADY: Research in stem cells and regenerative medicine is growing in scope, and its translation to the clinic is heralded by the recent initiation of controlled clinical trials with pluripotent derived cells. Unfortunately, stem cell 'treatments' are currently offered to patients outside of the controlled framework of scientifically sound research and regulated clinical trials. Both physicians and patients in reproductive medicine are often unsure about stem cells therapeutic options. STUDY DESIGN, SIZE, DURATION: An international working group was assembled to review critically the available scientific literature in both the human species and animal models. PARTICIPANTS/MATERIALS, SETTING, METHODS: This review includes work published in English until December 2014, and available through Pubmed. MAIN RESULTS AND THE ROLE OF CHANCE: A few areas of research in stem cell and reproductive medicine were identified: in vitro gamete production, endometrial regeneration, erectile dysfunction amelioration, vaginal reconstruction. The stem cells studied range from pluripotent (embryonic stem cells and induced pluripotent stem cells) to monopotent stem cells, such as spermatogonial stem cells or mesenchymal stem cells. The vast majority of studies have been carried out in animal models, with data that are preliminary at best. LIMITATIONS, REASONS FOR CAUTION: This review was not conducted in a systematic fashion, and reports in publications not indexed in Pubmed were not analyzed. WIDER IMPLICATIONS OF THE FINDINGS: A much broader clinical knowledge will have to be acquired before translation to the clinic of stem cell therapies in reproductive medicine; patients and physicians should be wary of unfounded claims of improvement of existing medical conditions; at the moment, effective stem cell treatment for reproductive diseases and alterations is not available. STUDY FUNDING/COMPETING INTERESTS: None. TRIAL REGISTRATION NUMBER: NA.

A new HLA-B allele, B*49:34, sequenced in a Spanish individual.

HLA-B*49:34 shows one nucleotide difference regarding B*49:01:01 at codon 66 (ATC>GTC, I66>V66).

Evidence for a role of matrix metalloproteinases and their inhibitors in primordial germ cell migration.

Understanding the mechanisms that enable migrating cells to reach their targets is of vital importance, as several pathologies, including cardiac defects and some tumours, are consequences of altered cell migration. With a view to evaluating if matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) play a role in the active migration of primordial germ cells (PGCs) from their place of origin in extra-embryonic sites towards their final destination in the developing gonads, we analysed the expression of mRNAs encoding nine MMPs and four TIMPs in migrating (E10.5) and post-migrating (E12.5) PGCs by means of quantitative polymerase chain reaction and the presence of MT1-MMP in the membrane of these cells. Our results show that PGCs express MMP-2, MMP-9, MMP-11, MT1-MMP, TIMP-1, TIMP-2 and TIMP-3 at both migrating and non-migrating stages. Comparing expression levels of MMP genes between E10.5 and E12.5 PGCs revealed higher expression in migrating PGCs of MT1- MMP (10.3-fold), MMP-2 (4.8-fold), MMP-11 (3.2-fold) and MMP-9 (2.1-fold). Similarly, the levels of TIMP gene expression were always higher in E12.5 genital ridge somatic cells: TIMP-3 (3.4-fold), TIMP-1 (2.4-fold) and TIMP-2 (1.8-fold). Moreover, the analysis at protein level showed the presence of MT1-MMP in the membrane of migrating PGCs whereas the expression of these metalloproteinase is not detected once the PGCs have reach the urogenital ridges and stop migrating. These results suggest that the change from the motile to non-motile phenotype that occurs during PGC maturation to gonocytes may be mediated in part by enhanced expression of MMPs in migrating PGCs together with higher expression of TIMPs in E12.5 genital ridges.

Complete meiosis from human induced pluripotent stem cells.

Gamete failure-derived infertility affects millions of people worldwide; for many patients, gamete donation by unrelated donors is the only available treatment. Embryonic stem cells (ESCs) can differentiate in vitro into germ-like cells, but they are genetically unrelated to the patient. Using an in vitro protocol that aims at recapitulating development, we have achieved, for the first time, complete differentiation of human induced pluripotent stem cells (hiPSCs) to postmeiotic cells. Unlike previous reports using human ESCs, postmeiotic cells arose without the over-expression of germline related transcription factors. Moreover, we consistently obtained haploid cells from hiPSCs of different origin (keratinocytes and cord blood), produced with a different number of transcription factors, and of both genetic sexes, suggesting the independence of our approach from the epigenetic memory of the reprogrammed somatic cells. Our work brings us closer to the production of personalized human gametes in vitro.

Structural and functional preservation of specific sequences of DNA and mRNA in apoptotic bodies from ES cells.

Retinoic acid-induced apoptosis of embryonic stem (ES) cells is an experimental system which resembles the physiological programmed cell death that occurs during differentiation in embryonic development. Our aim was to analyze the involvement of epigenetic modifications such as DNA methylation and chromatin structure in the apoptotic process and to investigate the metabolic activity of apoptotic bodies. We found a relationship between DNA methylation and apoptosis, shown by a dose-dependent induction of apoptosis after treatment with the inhibitor of DNA methylation 5-aza-2'-deoxycytidine. Interestingly, we found a slight demethylation of specific sequences of the U2afl-rs1 imprinted gene in those RA treated cells which were specifically undergoing apoptosis. In addition, apoptotic bodies exhibited an unexpected open chromatin conformation accessible to the endonuclease DNase-I. Furthermore, we observed a structural and functional preservation of specific DNA sequences and mRNA. These results suggest that biological activities, such as transcription or protein synthesis, could be maintained even towards the end of the apoptotic process.