Hematopoietic Stem Cell Therapy Research Articles

Gene Therapy: Recent Advancement and Challenges

Background: Gene therapy involves delivering therapeutic genomic material to a target tissue to modify expression of a protein or induce other characteristic changes. Recent advancements in the field, including FDA-approval of numerous gene therapies, are paving the way for future technological progress. While gene therapy can be either somatic or germline, most research and drug development has focused on somatic cells. In this article, we discuss the recent advancements and challenges associated with gene therapy.
 Main Text: There are multiple types of gene therapies, including hematopoietic stem cell therapy, CAR-T cell therapy, and Crispr/Cas9 gene therapy. Rare diseases and cancers are being researched to determine methods of treatment using gene therapy, and several clinical trials have been performed within the last decade to test the efficacy of new therapeutic drugs, many of them at least somewhat successful. However, gene therapy does pose some challenges, including large-scale manufacturing of vectors, precision of gene delivery to target tissue, and, most importantly, the immune responses of patients.
 Conclusions: The near future is an exciting time for new gene therapy technologies and strategies. Researchers and patients can look forward to new advancements in base editing, prime editing, and RNA-targeted editing technologies. Furthermore, future research can focus on new genetic targets, such as genes whose functions may still be unknown and epigenomic elements.

Routing pathway of syngeneic donor hematopoietic stem cells after simple intra-amniotic delivery

BackgroundWe sought to determine the pathway through which syngeneic hematopoietic stem cells (HSCs) delivered into the amniotic fluid can reach the fetal circulation. MethodsLewis rat fetuses were divided in two groups based on the content of intra-amniotic injections performed on gestational day 17 (E17; term=E21–22): either a suspension of luciferase-labeled syngeneic HSCs (n = 137), or acellular luciferase (n = 44). Samples from placenta, chorion, amnion, amniotic fluid, umbilical cord, and 8 fetal sites were procured at 5 daily time points thereafter until term for analysis. ResultsWhen controlled by acellular luciferase, donor HSCs were identified in the amnion, chorion, placenta, and amniotic fluid of fetuses receiving cells at all time points (p = 0.033 to <0.001), peaking first at the amnion and subsequently at the chorion and placenta. Cells could be detected in the fetal liver as early as day 1, progressively expanding to all the other fetal sites over time, in parallel to their increased presence in the chorion and placenta. ConclusionsThe chronology of syngeneic donor hematopoietic stem cell trafficking after intra-amniotic injection is suggestive of controlled routing through the gestational membranes and placenta. Hematogenous donor cell routing is a constituent of transamniotic hematopoietic stem cell therapy, significantly expanding its potential applications.

HEMATOPOIETIC STEM CELL TRANSPLANTATION AND CROHN'S DISEASE: POSITION PAPER FROM THE TRANSPLANTATION COMMITTEE OF THE BRAZILIAN GROUP FOR THE STUDY OF INFLAMMATORY BOWEL DISEASES (GEDIIB).

Crohn's disease (CD) is a relapse-remitting inflammatory bowel disease that can affect any part of the digestive system. This heterogeneous disease has multiple factors that contribute to an abnormal immune response to intestinal microorganisms. Treatment is based on the use of anti-inflammatories, corticosteroids, immunosuppressants and biologic biologic agents either alone or in combination. Surgical treatment is usual and, ten years after diagnosis, more than 80% of patients report having undergone surgical procedures related to the disease. Unfortunately, none of the treatments described offer a cure, and many cases become refractory or without therapeutic options. In this scenario, hematopoietic stem cell transplantation has been suggested because clinical remission was obtained in patients who had CD associated with malignant hematological diseases and an alternative since the first reports in 2010. In this report, the Transplantation Committee of the Brazilian Group for the Study of Inflammatory Bowel Diseases reviews the history and results of the procedure in patients with CD, detailing and discussing the various relevant points that permeate hematopoietic stem cell transplantation and cell therapy in this disease.

GITMO Registry Study on Allogeneic Transplantation in Patients Aged ≥60 Years from 2000 to 2017: Improvements and Criticisms

Today, allogeneic stem cell transplantation (allo-SCT) can be offered to patients up to age 70 to 72 years and represents one of the most effective curative treatments for many hematologic malignancies. The primary objective of the study was to collect data from the allo-SCTs performed in Italy between 2000 and 2017 in patients aged ≥60 years to evaluate the changes in safety and efficacy outcomes, as well as their distribution and characteristics over time. The Italian Group for Bone Marrow Transplantation, Hematopoietic Stem Cells and Cell Therapy (GITMO) AlloEld study (ClinicalTrials.gov identifier NCT04469985) is a retrospective analysis of allo-SCTs performed at 30 Italian transplantation centers in older patients (age ≥60 years) between 2000 and 2017 (n=1996). For the purpose of this analysis, patients were grouped into 3 time periods: time A, 2000 to 2005 (n=256; 12%); time B, 2006 to 2011 (n=584; 29%); and time C, 2012 to 2017 (n=1156; 59%). After a median follow-up of 5.6 years, the 5-year nonrelapse mortality (NRM) remained stable (time A, 32.8%; time B, 36.2%; and time C, 35.0%; P=.5), overall survival improved (time A, 28.4%; time B, 31.8%; and time C, 37.3%; P=.012), and the cumulative incidence of relapse was reduced (time A, 45.3%; time B, 38.2%; time C, 30.0%; P < .0001). The 2-year incidence of extensive chronic graft-versus-host disease was reduced significantly (time A, 17.2%; time B, 15.8%; time C, 12.2%; P=.004). Considering times A and B together (2000 to 2011), the 2-year NRM was positively correlated with the Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI) score; NRM was 25.2% in patients with an HCT-CI score of 0, 33.9% in those with a score of 1 or 2, and 36.1% in those with a score of 3 (P < .001). However, after 2012, the HCT-CI score was not significantly predictive of NRM. This study shows that the transplantation procedure in elderly patients became more effective over time. Relapse incidence remains the major problem, and strategies to prevent it are currently under investigation (eg, post-transplantation maintenance). The selection of patients aged ≥60 could be improved by combining HCT-CI and frailty assessment to better predict NRM.

TAMI-78. STEM CELL IMMUNOTHERAPY MODULATES IMMUNOREGULATORY PATHWAYS IN THE TUMOR MICROENVIRONMENT

Abstract INTRODUCTION A major obstacle in efficacious therapeutics against high-grade gliomas has been an inability to overcome powerful regulatory mechanisms within the TME that hamper immune activation. Fortunately, immunotherapy has enabled the enhancement of immune activation within the TME through adoptive immunotherapy and checkpoint inhibition. We found that co-transfer of hematopoietic stem cells (HSCs) with either adoptive immunotherapy or PD-1 blockade significantly improves therapeutic outcomes by manipulating the cellular components that make up the TME in high-grade gliomas. HSC co-transfer with immunotherapy leads to increased in situ downregulation of multiple immune regulatory pathways, activation of tumor-reactive T cells, and significant reduction in the frequency of MDCs and TAMs within the TME. METHODS C57BL/6 mice with orthotopic KR158B-gliomas received either adoptive immunotherapy using activated tumor-reactive T cells or αPD-1, either with or without HSC co-transfer. After treatment of late-stage tumors, brains were sectioned and digital spatial profiling (NanoString GeoMx) of the TME was conducted in situ. Briefly, tumor-bearing brain sections were stained for nuclei, CD3, CD45, and GFP (HSC-derived cells); regions of interest (ROIs) containing 200 nuclei were selected and processed for whole genome sequencing. Areas rich in immune cells within the TME were chosen as ROIs and compared between groups. Results were corroborated with flowcytometry and PCR. RESULTS Mice that received HSCs with either adoptive cellular therapy or αPD-1 had reductions in expression of multiple regulatory markers in the TME including iNOS, TGFβ, and PD-L1. This was accompanied by reductions in the frequencies of MDSCs and TAMs. An increased relative abundance of activated CD8+ T cells within the TME was also observed. Interestingly, we found that HSC-derived cells provided rich amounts of dendritic cells at the TME when co-transferred with immunotherapy. Host-derived myeloid cells were significantly displaced from the TME in mice receiving HSC plus adoptive cellular therapy or αPD-1.

CD66e Enrichment Enhances Repopulation of Human Long-Term Hematopoietic Stem Cells

Gene-modified hematopoietic stem cells (HSCs) therapy has demonstrated remarkable success for the treatment of inherited blood disorders. As the origin of hematologic hierarchy, HSCs play an essential role in sustaining life-long hematopoiesis. HSCs identification via reliable and robust bio-markers could facilitate the development of HSC gene therapy. Previous studies showed that long-term hematopoietic stem cells (LT-HSCs) were enriched in the Lin -CD34 +CD38 -CD45RA -CD90 +CD49f + population which could support long-term hematopoietic reconstitution. However, several of these surface markers proved to be unreliable when ex vivo culturing, such as CD38 and CD49f. Thus, HSCs characterization is still hindered by lacking bona-fide bio-markers, and consequently identification of long-term HSCs still needs time-consuming in vivo transplantation. To this end, we performed in vitro screening and comprehensive functional evaluation to identify a novel surface marker of human HSCs.During initial screening, a cell surface antigen screen panel (including 242 human cell surface markers) and human CD34 and CD90 antibodies were used to perform flow cytometry analysis on CD34 + HSPCs enriched from umbilical cord blood. Compared with CD34 + cell population, we found that CD66 (a,c,d,e), CD200 and CD48 positive cells were more enriched in CD34 +CD90 + subset. Previous studies indicated that HSCs cannot be maintained during in vitro culturing. By tracking these candidate surface markers based on this principle, CD66e was selected as the potential HSCs bio-marker.Next, we examined the in vivo hematologic repopulating potential of HSCs by limiting dilution assay (LDA) on immune-deficient mouse model. We sorted CD66e + and CD66e - subsets from CD34 +CD90 +CD45RA - subpopulation, and transplanted into irradiated NOD-scid Il2rg −/− (NPG) mice respectively. At week16 post-transplantation, in contrast to the CD66e - group, CD66e + cells exhibited significantly higher reconstitution in peripheral blood (PB), bone marrow (BM) and spleen. Engraftment dynamics revealed that the CD66e - group were only capable of reconstitution 4 weeks post transplantation, even at the highest initial cell dose. Moreover, the CD66e - group displayed impaired multi-lineage differentiation pattern, especially in PB and BM samples, while the CD66e + group presented a robust multi-lineage reconstitution. Notably, LDA results showed that the CD66e + cells within CD34 +CD90 +CD45RA - population contained 1 out of 529 SCID repopulating cells (SRC), almost 60-fold greater than the CD66e - fraction. To further investigate the long-term repopulating potential of the CD66e + cells, we performed the secondary transplantation collected from the BM cells of primary recipients. CD66e + cells presented significant higher repopulating activity than CD66e- subset in the secondary recipients. These findings reveal that the major cells with homing and long-term reconstitution capacity among CD34 +CD90 +CD45RA - cells were CD66e positive.In order to determine the transcriptional profile of CD66e + cells, we performed RNA-sequencing analysis using the population of CD34 + cells, CD34 +CD90 +CD45RA - cells, CD66e + and CD66e - cells within CD34 +CD90 +CD45RA - subset. Remarkably, compared with other groups, the CD66e + cells displayed a bias toward the signature of HSC and early progenitors such as LMPP and CLP. Moreover, gene set enrichment analysis showed that hematopoietic lineage and long-term potentiation-related genes were highly enriched in the CD66e + cells. Further qRT-PCR experiment confirmed that several HSC-related genes were significantly higher expressed in CD34 +CD90 +CD45RA -CD66e + cells, compared to CD66e - population or CD34 + HSPCs, suggesting that the gene expression profile of CD66e + cells is reminiscent of HSC signature.Altogether, we demonstrate that CD66e is a robust functional HSC bio-marker that CD66e-positive population among CD34 +CD90 +CD45RA - cells exhibit typical HSC signature, enhanced in vivo engraftment potential and robust multilineage differentiation pattern, which will provide an invaluable tool to investigate the origin of human HSCs, paving the way for the therapeutic application. [Display omitted] DisclosuresFang: EdiGene, Inc.: Current Employment.

Efficacy and Safety of Parsaclisib in Patients with Relapsed or Refractory Follicular Lymphoma: Primary Analysis from a Phase 2 Study (CITADEL-203)

Efficacy and Safety of Parsaclisib in Patients with Relapsed or Refractory Follicular Lymphoma: Primary Analysis from a Phase 2 Study (CITADEL-203)

SARS-CoV-2-reactive antibody detection after SARS-CoV-2 vaccination in hematopoietic stem cell transplant recipients: Prospective survey from the Spanish Hematopoietic Stem Cell Transplantation and Cell Therapy Group.

This is a multicenter prospective observational study that included a large cohort (n = 397) of allogeneic (allo‐HSCT; (n = 311) and autologous (ASCT) hematopoietic stem cell transplant (n = 86) recipients who were monitored for antibody detection within 3–6 weeks after complete severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) vaccination from February 1, 2021, to July 20, 2021. Most patients (n = 387, 97.4%) received mRNA‐based vaccines. Most of the recipients (93%) were vaccinated more than 1 year after transplant. Detectable SARS‐CoV‐2‐reactive antibodies were observed in 242 (78%) of allo‐HSCT and in 73 (85%) of ASCT recipients. Multivariate analysis in allo‐HSCT recipients identified lymphopenia < 1 × 109/ml (odds ratio [OR] 0.33, 95% confidence interval [95% CI] 0.16–0.69, p = .003), active graft versus host disease (GvHD; OR 0.51, 95% CI 0.27–0.98, p = .04) and vaccination within the first year of transplant (OR 0.3, 95% CI 0.15–0.9, p = .04) associated with lower antibody detection whereas. In ASCT, non‐Hodgkin's lymphoma (NHL; OR 0.09, 95% CI 0.02–0.44, p = .003) and active corticosteroid therapy (OR 0.2, 95% CI 0.02–0.87, p = .03) were associated with lower detection rate. We report an encouraging rate of SARS‐CoV‐2‐reactive antibodies detection in these severe immunocompromised patients. Lymphopenia, GvHD, the timing of vaccine, and NHL and corticosteroids therapy should be considered in allo‐HSCT and ASCT, respectively, to identify candidates for SARS‐CoV‐2 antibodies monitoring.

A Review on Hematopoietic Stem Cell Treatment for Epilepsy.

Epilepsy responds to pharmacotherapy in its initial stages. The response of some forms of epilepsy, like the refractory epilepsy, is extremely low. Surgical management of epilepsy is associated with complications, which necessitates the search for novel and modern strategies for the treatment of epilepsy. Neuroprotection and neuronal regeneration are the major targets that must be accomplished by the new strategies. Hematopoietic Stem Cell (HSCs) therapy for epilepsy has shown promising results in pre-clinical studies with marginal clinical effects. This review explores the characteristics, mechanism of action, and clinical significance of HSCs therapy for the treatment of epilepsy.

Hematopoietic stem cell-derived functional osteoblasts exhibit therapeutic efficacy in a murine model of osteogenesis imperfecta.

Currently, there is no cure for osteogenesis imperfecta (OI)-a debilitating pediatric skeletal dysplasia. Herein we show that hematopoietic stem cell (HSC) therapy holds promise in treating OI. Using single-cell HSC transplantation in lethally irradiated oim/oim mice, we demonstrate significant improvements in bone morphometric, mechanics, and turnover parameters. Importantly, we highlight that HSCs cause these improvements due to their unique property of differentiating into osteoblasts/osteocytes, depositing normal collagen-an attribute thus far assigned only to mesenchymal stem/stromal cells. To confirm HSC plasticity, lineage tracing was done by transplanting oim/oim with HSCs from two specific transgenic mice-VavR, in which all hematopoietic cells are GFP+ and pOBCol2.3GFP, where GFP is expressed only in osteoblasts/osteocytes. In both models, transplanted oim/oim mice demonstrated GFP+ HSC-derived osteoblasts/osteocytes in bones. These studies unequivocally establish that HSCs differentiate into osteoblasts/osteocytes, and HSC transplantation can provide a new translational approach for OI.

Hematopoietic Stem Cell Therapy for Wiskott-Aldrich Syndrome: Improved Outcome and Quality of Life.

The Wiskott–Aldrich syndrome (WAS) is an X-linked disorder caused by mutations in the WAS gene resulting in congenital thrombocytopenia, eczema, recurrent infections and an increased incidence of autoimmune diseases and malignancies. Without curative therapies, affected patients have diminished life expectancy and reduced quality of life. Since WAS protein (WASP) is constitutively expressed only in hematopoietic stem cell-derived lineages, hematopoietic stem cell transplantation (HSCT) and gene therapy (GT) are well suited to correct the hematologic and immunologic defects. Advances in high-resolution HLA typing, new techniques to prevent GvHD allowing the use of haploidentical donors, and the introduction of reduced intensity conditioning regimens with myeloablative features have increased overall survival (OS) to over 90%. The development of GT for WAS has provided basic knowledge into vector selection and random integration of various viral vectors into the genome, with the possibility of inducing leukemogenesis. After trials and errors, inactivating lentiviral vectors carrying the WAS gene were successfully evaluated in clinical trials, demonstrating cure of the disease except for insufficient resolution of the platelet defect. Thus, 50 years of clinical evaluation, genetic exploration and extensive clinical trials, a lethal syndrome has turned into a curable disorder.

Trehalose: effect on cryopreservation of umbilical cord blood-derived hematopoietic stem cells

Introduction: Concerns over dimethyl sulfoxide (DMSO) toxicity, related to adverse reactions after hematopoietic stem cells (HSCs) therapy, warrant the development of an optimized DMSO-free or DMSO-reduced cryopreservation protocol for the quality and safety of HSCs. In this regard, the ideal concentration of trehalose, as a non-toxic natural cryoprotectant, is still an area of research. Based on the outcome of our previous study on lower concentrations of trehalose, the present study was focused on evaluating its cryoprotective efficacy at an increased concentration (0.5 M) on HSCs compared to 10% DMSO. This is a laboratory-based experimental study. Material and methods: The separated mononuclear cells collected from umbilical cord blood were set for culture up to two passages to get HSCs. The two different concentrations of trehalose, with and without 5% DMSO, were considered as freezing media for the preservation of the harvested HSCs in a slow freezing set up. Two sequential functional assays, viability followed by hematopoietic colony-forming unit assay, were performed with post-thawed cells of freezing media used in this study. Seventeen cord blood samples were selected. Results: Study results revealed 0.5 M trehalose and DMSO 5% showed the highest viability of 91.8 ±2.8% of HSCs. 5% DMSO inclusion to trehalose (0.5 M) ameliorated hematopoietic colonies such as erythroid and myeloid colonies with no significant difference from that of 10% DMSO. Conclusion: 0.5 M trehalose has proved to be a better concentration than 10% DMSO alone. This experimental study needs further transplantation-based clinical trials using post-thawed cells to ensure the safety of preserved HSCs from cord blood and other sources.

Trehalose: effect on cryopreservation of umbilical cord blood-derived hematopoietic stem cells

Introduction: Concerns over dimethyl sulfoxide (DMSO) toxicity, related to adverse reactions after hematopoietic stem cells (HSCs) therapy, warrant the development of an optimized DMSO-free or DMSO-reduced cryopreservation protocol for the quality and safety of HSCs. In this regard, the ideal concentration of trehalose, as a non-toxic natural cryoprotectant, is still an area of research. Based on the outcome of our previous study on lower concentrations of trehalose, the present study was focused on evaluating its cryoprotective efficacy at an increased concentration (0.5 M) on HSCs compared to 10% DMSO. This is a laboratory-based experimental study. Material and methods: The separated mononuclear cells collected from umbilical cord blood were set for culture up to two passages to get HSCs. The two different concentrations of trehalose, with and without 5% DMSO, were considered as freezing media for the preservation of the harvested HSCs in a slow freezing set up. Two sequential functional assays, viability followed by hematopoietic colony-forming unit assay, were performed with post-thawed cells of freezing media used in this study. Seventeen cord blood samples were selected. Results: Study results revealed 0.5 M trehalose and DMSO 5% showed the highest viability of 91.8 ±2.8% of HSCs. 5% DMSO inclusion to trehalose (0.5 M) ameliorated hematopoietic colonies such as erythroid and myeloid colonies with no significant difference from that of 10% DMSO. Conclusion: 0.5 M trehalose has proved to be a better concentration than 10% DMSO alone. This experimental study needs further transplantation-based clinical trials using post-thawed cells to ensure the safety of preserved HSCs from cord blood and other sources.

Loes Score: Clinical and Radiological Profile of 22 Patients of X-Linked Adrenoleukodystrophy: Case Series from a Single Center.

Introduction X-linked adrenoleukodystrophy (X-ALD) is a devastating disease with a wide spectrum of presentation ranging from asymptomatic to a rapidly progressive childhood cerebral form. The gene responsible for adrenoleukodystrophy is ABCD1 gene, required for β oxidation of fatty acids in various tissues. While biochemical and molecular techniques are available to confirm the diagnosis, brain magnetic resonance imaging (MRI) utilizing Loes score has been used for both prognosis and timely direction of hematopoietic stem cell therapy. Materials and Methods During the study period of 2016 to 2020, 22 individuals including 19 individuals with features suggestive of X-ALD and 3 asymptomatic siblings were evaluated from a single center in North India. After biochemical and molecular confirmation of the disease, detailed clinical and radiological findings using MRI brain were documented. A radiological scoring pattern proposed by Loes was employed to identify the severity of the disorder. Results The most common clinical presentations were visual difficulty and muscular weakness (58%). All symptomatic individuals had classic neuroimaging findings in the form of hyperintensities involving the parieto-occipital area and splenium of corpus callosum. Severe involvement in the form of global atrophy was observed in 52.6% of individuals. Asymptomatic siblings also showed neurological involvement based on MRI with highest Loes score of 9 in one individual. Conclusion This case series describes the clinical and radiological profile and employment of Loes score in individuals with X-ALD. Early identification of asymptomatic individuals by neuroimaging and use of Loes severity score for monitoring and disease progression will help in making therapeutic decisions in a timely manner.

Cystatin C level is associated with the recovery of renal function in cancer patients after onset of acute kidney injury.

The risk of injury to the kidney can be significantly exacerbated by the presence of tumors and the effects of related treatments. Kidney injury associated with cancer is common in multiple myeloma, tumor lysis syndrome, hematopoietic stem cell therapy, and chemotherapy. Cancer patients are at increased risk of infection, sepsis, tumor lysis syndrome, drug-related toxicity, and other comorbidities, leading to a significantly increased risk of acute kidney injury (AKI). This study retrospectively analyzed the clinical data of AKI in cancer patients and explored the predictive value of Cystatin C (CysC) in the prognosis of cancer patients with AKI. Cancer patients attending the Fifth People's Hospital of Shenyang from April 2014 to March 2019 were enrolled according to inclusion and exclusion criteria. Cancer patients with AKI were divided into two groups according to the changes in renal function during the follow-up period: a renal function recovery group and a nonrecovery group. The differences in baseline data of the two groups were compared. Logistic univariate and multivariate regression analyses were conducted to determine the risk of renal function failure. A total of 3,127 cases were included. Among them, 659 cases (21.1%) had AKI, and 2,468 cases had no AKI. Among the 659 AKI patients, 473 (71.8%) patients' renal function recovered, while 186 (28.2%) did not. Logistic univariate and multivariate regression analyses indicated that age [odds ratio (OR) =1.133, 95% confidence interval (CI): 1.064-1.219], diabetes (OR =1.226, 95% CI: 1.093-1.385), chronic kidney disease (CKD) (OR =1.347, 95% CI: 1.108-1.624), hematological malignancies (OR =1.174, 95% CI: 1.063-1.311), chemotherapy (OR =1.119, 95% CI: 1.055-1.304), systolic blood pressure (OR =1.108, 95% CI: 1.062-1.267), serum creatinine (Scr) (OR =1.262, 95% CI: 1.105-1.446), and CysC (OR =1.416, 95% CI: 1.251-1.739) were related to the failure of renal function to recover after AKI. Baseline CysC level is associated with the occurrence of AKI in cancer patients and a failure to recover renal function during follow-up.

Standardization and Accreditation in Haemopoietic Stem Cell Transplantation - an Asia Pacific Perspective.

Standardization and formal accreditation of practices related to hematopoietic stem cell transplantation (HSCT) and therapies using hematopoietic-derived cellular products aim to promote quality in clinical and laboratory practice and provide knowledge to all stakeholders of centers. This article refers to three aspects of these processes starting with the importance of accurate viable CD 34 enumeration in HSCT. A highly accurate method of enumeration and a robust EQAS program is required, especially during the current COVID-19 pandemic. The second section shares experiences with FACT-JACIE accreditation at the Singapore General Hospital demonstrating how accreditation is part of continuous improvement and not only a destination. This journey can be difficult in many HSCT centers of low- and middle-income countries (LMICs) because of the intensive and rigorous requirements of the internationally accredited models. Hence, in LMICs, a staged movement toward establishing such standards must be considered. This approach is presented in the third section of the article with data on the current situation in countries reporting to the APBMT registry.

Mucopolysaccharidoses I and II: Brief Review of Therapeutic Options and Supportive/Palliative Therapies.

Purpose. Mucopolysaccharidoses (MPS) are group of inherited lysosomal storage diseases caused by mutations of enzymes involved in catalyzing different glycosaminoglycans (GAGs). MPS I and MPS II exhibit both somatic and neurological symptoms with a relatively high disease incidence. Hematopoietic stem cell therapy (HSCT) and intravenous enzyme replacement therapy (ERT) have had a significant impact on the treatment and comprehension of disease. This review is aimed at providing a comprehensive evaluation of the pros and cons of HSCT and ERT, as well as an up-to-date knowledge of new drugs under development. In addition, multiple disease management strategies for the uncontrollable manifestations of MPS I and MPS II to improve patients' quality of life are presented. Findings. Natural history of MPS I and MPS II shows that somatic and neurological symptoms occur earlier in severe forms of MPS I than in MPS II. ERT increases life expectancy and alleviates some of the somatic symptoms, but musculoskeletal, ophthalmological, and central nervous system (CNS) manifestations are not controlled. Additionally, life-long treatment burdens and immunogenicity restriction are unintended consequences of ERT application. HSCT, another treatment method, is effective in controlling the CNS symptoms and hence has been adopted as the standard treatment for severe types of MPS I. However, it is ineffective in MPS II, which can be explained by the relatively late diagnosis. In addition, several factors such as transplant age limits or graft-versus-host disease in HSCT have limited its application for patients. Novel therapies, including BBB-penetrable-ERT, gene therapy, and substrate reduction therapy, are under development to control currently unmanageable manifestations. BBB-penetrable-ERT is being studied comprehensively in the hopes of being used in the near future as a method to effectively control CNS symptoms. Gene therapy has the potential to “cure” the disease with a one-time treatment rather than just alleviate symptoms, which makes it an attractive treatment strategy. Several clinical studies on gene therapy reveal that delivering genes directly into the brain achieves better results than intravenous administration in patients with neurological symptoms. Considering new drugs are still in clinical stage, disease management with close monitoring and supportive/palliative therapy is of great importance for the time being. Proper rehabilitation therapy, including physical and occupational therapy, surgical intervention, or medications, can benefit patients with uncontrolled musculoskeletal, respiratory, ophthalmological, and neurological manifestations.

Hematopoietic stem cell transplantation in systemic sclerosis: Yes!! BUT. . .

Systemic sclerosis is a chronic multisystem, autoimmune disease with high mortality, and to date, has no effective approved therapy. For patients with the most severe forms of systemic sclerosis, autologous hematopoietic stem cell therapy has been proven to be effective, as demonstrated by three randomized controlled clinical trials and at least two registry studies. In the controlled studies, autologous hematopoietic stem cell therapy was shown to improve mortality, skin involvement, quality-of-life, and function compared with patients treated with intravenous cyclophosphamide. There is significant transplant-related mortality associated with autologous hematopoietic stem cell therapy, as well as infectious and noninfectious serious adverse events, including cardiac and renal compromise. Although the results of autologous hematopoietic stem cell therapy clinical trials to date are highly encouraging, a number of important unanswered questions remain. These include the following: What is the optimal transplant regimen; can the spectrum of systemic sclerosis patients who respond to autologous hematopoietic stem cell therapy be expanded; how can disease relapse following autologous hematopoietic stem cell therapy be predicted and managed; can treatment-related toxicity and mortality be mitigated; can response or toxicity be predicted; and finally, is there a place for allogeneic stem cell transplants in systemic sclerosis? Systemic sclerosis is an autoimmune disease with multiple immunological, vascular, and fibrotic abnormalities. Immunosuppressive therapy is frequently used, but to date its efficacy has been generally modest. Stem cell transplantation is the most potent immunosuppressive therapy currently available, and as discussed below, may have an important role in the management of systemic sclerosis.

COVID-19 and Stem Cell Transplantation; Results from the Prospective Survey By the Infectious Diseases Working Party of the European Society for Blood and Marrow Transplantation (EBMT) and the Spanish Hematopoietic Stem Cell Transplantation and Cell Therapy Group (GETH)

COVID-19 is a severe infectious complication in patients with underlying medical conditions such as having undergone hematopoietic stem cell transplantation (HCT). This prospective survey reports outcome on 272 COVID-19 patients from 19 countries having undergone allogeneic (n = 175) or autologous (n = 97) HCT reported to the EBMT registry or to the GETH. All patients had the diagnosis of SARS-CoV-2 documented by PCR. Patients were included in this analysis if COVID-19 diagnosis was before April 10, 2020. The overall survival was estimate by using the Kaplan Meier methods, considering the death due to any cause as an event and the time from COVID-19 infection to the latest follow-up as survival time; difference between groups were tested by the log-rank test. Univariate and multivariate risk factor analysis for overall survival were performed with the Cox regression model.The median age was 54.4 years (1.0 - 80.3) for allogeneic and 60.9 years (7.7 - 73.4) for autologous HCT patients. 20 patients were children (< 18 years of age; median age 11.3 (1.0 - 16.9)). The median time from HCT to diagnosis of COVID-19 was 13.7 months (0.2 - 254.3) in allogeneic and 25.0 months (-0.9 - 350.3) in autologous recipients. Lower respiratory tract disease (LRTD) developed in 84.8% and 21.5% were admitted to an intensive care unit (ICU). At the time of analysis, 68/238 (28.6%) patients had died (47/155 allogeneic patients; 21/83 autologous patients). No follow-up had been received on 34 patients. The median time from infection to death was 19 days (0-102). Five patients were reported to have other primary causes of death than COVID-19. Of the patients reported to be alive, the median follow-up was 44 days. 144 (84.7%) patients (93 allogeneic; 51 autologous) had virologic resolution of the COVID-19 infection having at least one negative PCR. 26 patients were alive and known to be still COVID-19 positive (15 allogeneic; 11 autologous). For 34 patients the resolution status was unknown. Factors influencing the likelihood of resolution in multivariate analysis were underlying diagnosis (p=.01) and longer time from transplant to diagnosis of COVID-19 (p=.035).Overall survival at 6 weeks from COVID-19 diagnosis was 76.8% and 83.8% in allogeneic and autologous HCT recipients (p =ns), respectively (figure 1). Children (n=20) tended to do better with a 6-week survival of 95.0% although the difference was not significantly different (p =.12). In multivariate analysis of the total population older age (HR 1.26; 95% CI 1.05 - 1.51; p = .01) increased the risk and better performance status decreased the risk for fatal outcome (HR 0.79; 95% CI 0.69 - 0.90; p = .0003). The same factors had significant impact on overall survival in allogeneic HCT recipients (age HR 1.28; 95% CI 1.05 - 1.55; p=.01; performance status HR 0.79; 95% CI 0.68 - 0.92); p=.002) while only age impacted survival among autologous HCT patients (data not shown). Other transplant factors such as underlying diagnosis, time from HCT to diagnosis of COVID-19, graft-vs-host disease, or ongoing immunosuppression did not have a significant impact on overall survival.We conclude that HCT patients are at an increased risk compared to the general population to develop LRTD, require admission to ICU, and have increased mortality in COVID-19.Figure 1DisclosuresDuarte:Incyte Corporation: Other: Has received speaker and advisor fees. Kwon:Jazz: Consultancy, Honoraria; Gilead: Consultancy, Honoraria; Novartis: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria. Mielke:Novartis: Honoraria, Other: received via my institution, Speakers Bureau; Celgene/BMS: Honoraria, Other: received via my institution , Speakers Bureau; Bellicum: Honoraria, Other: received via my institution, Speakers Bureau; Kite/Gilead: Honoraria, Other: received via my institution , Speakers Bureau; Miltenyi: Honoraria, Membership on an entity’s Board of Directors or advisory committees, Other: received via my institution , Speakers Bureau; KIADIS Pharma: Honoraria, Other: received via my institution , Speakers Bureau; DNA Prime: Honoraria, Other: received via my institution , Speakers Bureau. López Jiménez:MSD: Speakers Bureau; Roche: Research Funding, Speakers Bureau; Takeda: Speakers Bureau; Janssen: Research Funding, Speakers Bureau; Abbvie: Research Funding, Speakers Bureau; Gilead: Research Funding, Speakers Bureau.

Cutaneous Wound Generation in Diabetic NOD/SCID Mice and the Use of Nanofiber-Expanded Hematopoietic Stem Cell Therapy.

Despite significant advances in diabetic wound management, diabetic wounds remain a significant global problem that decreases patient's quality of life, and chronic wounds may lead to amputation and death to the patients. To develop a potential regenerative therapy, a xenogeneic transplantation compatible laboratory model needs to be developed. This procedure demonstrates how to isolate hematopoietic stem cells (CD133+) from human umbilical cord blood, expand CD34+ stem cells using a nanofiber scaffold (polyether sulfone-coated and amino group-treated), induce diabetes in immunocompromised (NOD/SCID) mice, induce a cutaneous wound in mice, and how to treat the wound with the nanofiber-expanded CD34+ stem cells. This protocol also shows how to measure wound healing.