Enabling mRNA medicine for brain tumors

mRNA is a new class of drugs that has the potential to revolutionize the treatment of brain tumors. Thanks to the COVID-19 mRNA vaccines and numerous therapy-based clinical trials, it is now clear that lipid nanoparticles (LNPs) are a clinically viable means to deliver RNA therapeutics. However, LNP-mediated mRNA delivery to brain tumors remains elusive. Over the past decade, numerous studies have shown that tumor cells communicate with each other via small extracellular vesicles, which are around 100 nm in diameter and consist of lipid bilayer membrane similar to synthetic lipidbased nanocarriers. We hypothesized that rationally designed LNPs based on extracellular vesicle mimicry would enable efficient delivery of RNA therapeutics to brain tumors without undue toxicity. We synthesized LNPs using four components similar to the formulation used in the mRNA COVID19 vaccines (Moderna and Pfizer): ionizable lipid, cholesterol, helper lipid and polyethylene glycol (PEG)-lipid. For the in vitro screen, we tested ten classes of helper lipids based on their abundance in extracellular vesicle membranes, commercial availability, and large-scale production feasibility while keeping rest of the LNP components unchanged. The transfection kinetics of GFP mRNA encapsulated in LNPs and doped with 16 mol% of helper lipids was tested using GL261, U87 and SIM-A9 cell lines. Several LNP formations resulted in stable transfection (upto 5 days) of GFP mRNA in all the cell lines tested in vitro. The successful LNP candidates (enabling >80% transfection efficacy) were then tested in vivo to deliver luciferase mRNA to brain tumors via intrathecal administration in a syngeneic glioblastoma (GBM) mouse model, which confirmed luciferase expression in brain tumors in the cortex. LNPs were then tested to deliver Cre recombinase mRNA in syngeneic GBM mouse model genetically modified to express tdTomato under LoxP marker cassette that enabled identification of LNP targeted cells. mRNA was successfully delivered to tumor cells (70-80% transfected) and a range of different cells in the tumor microenvironment, including tumor-associated macrophages (80-90% transfected), neurons (31- 40% transfected), neural stem cells (39-62% transfected), oligodendrocytes (70-80% transfected) and astrocytes (44-76% transfected). Then, LNP formulations were assessed for delivering Cas9 mRNA and CD81 sgRNA (model protein) in murine syngeneic GBM model to enable gene editing in brain tumor cells. Sanger sequencing showed that CRISPR-Cas9 editing was successful in ~94% of brain tumor cells in vivo. In conclusion, we have developed a library of safe LNPs that can transfect GBM cells in vivo with high efficacy. This technology can potentially be used to develop novel mRNA therapies for GBM by delivering single or multiple mRNAs and holds great potential as a tool to study brain tumor biology.

Mid-density Gene Expression profiling of SARSCOV-2 infected samples using Applied BiosystemsTM TaqManTM Flexible Array Panels

Background/Objectives: The broad spectrum of clinical manifestations from SARS-COV-2 infection and observed risk factors for severe disease highlight the importance of understanding molecular mechanisms underlying SARS-CoV-2 associated disease pathogenesis. Research studies have identified a large number of host proteins that play roles in viral entry, innate immune response, or immune signalling during infection. The ability to interrogate subsets of these genes simultaneously within SARSCOV-2 infected samples is critical to understanding how their expression contribute to phenotypic variability of the disease caused by the pathogen. Method(s): 30 Nasopharyngeal swab were obtained and included SARS-CoV-2 infected and control samples. RNA was extracted, reverse transcribed and loaded onto flexible TaqMan array panels designed specifically for targeting the most cited genes related to SARS-COV-2 entry and restriction factors as well as cytokines, chemokines, and growth factors involved in the pathogenesis. Result(s): Our data indicated that not only were the levels of several of these host factors differentially modulated between the two study groups, but also that SARS-CoV-2 infected subjects presented with greater frequency of several important inflammatory cytokines and chemokines such as CCL2, CCL3, IFNG, entry receptors such as ACE2, TMRPS11A, and host restriction factors including LY6E and ZBP1. Conclusion(s): TaqMan array plates provide a fast, midthroughput solution to determine the levels of several virus and host-associated factors in various cell types and add to our understanding of how the pathogenesis may vary depending on gender, age, infection site etc.

Biodegradable Polyester Nanoparticle Vaccines Deliver Self-Amplifying mRNA in Mice at Low Doses

Delivery of self-amplifying mRNA (SAM) has high potential for infectious disease vaccination due to its self-adjuvanting and dose-sparing properties. Yet a challenge is the susceptibility of SAM to degradation and the need for SAM to reach the cytosol fully intact to enable self-amplification. Lipid nanoparticles are successfully deployed at incredible speed for mRNA vaccination, but aspects such as cold storage, manufacturing, efficiency of delivery, and the therapeutic window can benefit from further improvement. To investigate alternatives to lipid nanoparticles, a class of >200 biodegradable end-capped lipophilic poly(beta-amino ester)s (PBAEs) that enable efficient delivery of SAM in vitro and in vivo as assessed by measuring expression of SAM encoding reporter proteins is developed. The ability of these polymers to deliver SAM intramuscularly in mice is evaluated, and a polymer-based formulation that yields up to 37-fold higher intramuscular (IM) expression of SAM compared to injected naked SAM is identified. Using the same nanoparticle formulation to deliver a SAM encoding rabies virus glycoprotein, the vaccine elicits superior immunogenicity compared to naked SAM delivery, leading to seroconversion in mice at low RNA injection doses. These biodegradable nanomaterials may be useful in the development of next-generation RNA vaccines for infectious diseases.Copyright © 2023 The Authors. Advanced Therapeutics published by Wiley-VCH GmbH.

Increases in expression of carbohydrate sulfotransferases CHST11 and CHST15 and decline in N-acetylgalactosamine-4-sulfatase (Arylsulfatase B, ARSB) require phospho-p38-MAPK following exposure to SARS-CoV-2 spike protein receptor binding domain in human a

Objective: Immunohistochemistry of post-mortem lung tissue from Covid-19 patients with diffuse alveolar damage demonstrated marked increases in chondroitin sulfate and CHST15 and decline in N-acetylgalactosamine-4-sulfatase. Studies were undertaken to identify the mechanisms involved in these effects. Method(s): Human primary small airway epithelial cells (PCS 301-010;ATCC) were cultured and exposed to the SARSCoV- 2 spike protein receptor binding domain (SPRBD;AA: Lys310-Leu560;Amsbio). Expression of the spike protein receptor, angiotensin converting enzyme 2 (ACE2), was enhanced by treatment with Interferon-beta. Promoter activation, DNA-binding, RNA silencing, QPCR, Western blots, ELISAs, and specific enzyme inhibitors were used to elucidate the underlying molecular mechanisms. Result(s): Treatment of the cultured cells by the SPRBD led to increased CHST15 and CHST11 expression and decline in ARSB expression. Sulfotransferase activity, total chondroitin sulfate, and sulfated glycosaminoglycan (GAG) content were increased. Phospho-T180/T182-p38-MAPK and phospho- S423/S425-Smad3 were required for the activation of the CHST15 and CHST11 promoters. Inhibition by SB203580, a phospho-p38 MAPK inhibitor, and by SIS3, a Smad3 inhibitor, blocked the CHST15 and CHST11 promoter activation. SB203580 reversed the SPRBD-induced decline in ARSB expression, but SIS3 had no effect on ARSB expression or promoter activation. Phospho-p38 MAPK was shown to reduce retinoblastoma protein (RB) S807/S811 phosphorylation and increase RB S249/T252 phosphorylation. E2F-DNA binding declined following exposure to SPRBD, and SB203580 reversed this effect. This indicates a mechanism by which SPRBD, phospho-p38 MAPK, E2F, and RB can regulate ARSB expression and thereby impact on chondroitin 4-sulfate and dermatan sulfate and molecules that bind to these sulfated GAGs, including Interleukin-8, bone morphogenetic protein-4, galectin-3 and SHP-2 (Src homology region 2-containing protein tyrosine phosphatase 2). Conclusion(s): The enzyme ARSB is required for the degradation of chondroitin 4-sulfate and dermatan sulfate, and accumulation of these sulfated GAGs can contribute to lung pathophysiology, as evident in Covid-19. Some effects of the SPRBD may be attributable to unopposed Angiotensin II, when Ang1-7 counter effects are diminished due to binding of ACE2 with the SARS-CoV-2 spike protein and reduced production of Ang1-7. Aberrant cell signaling and activation of the phospho-p38 MAPK and Smad3 pathways increase CHST15 and CHST11 production, which can contribute to increased chondroitin sulfate in infected cells. Decline in ARSB may occur as a consequence of effects of phospho-p38 MAPK on RB phosphorylation and E2F1 availability. Decline in ARSB and the resulting impaired degradation of sulfated GAGs have profound consequences on cellular metabolic, signaling, and transcriptional events. Funding is VA Merit Award.Copyright © 2023 The American Society for Biochemistry and Molecular Biology, Inc.

Association of SARS-COV-2 viral RNAemia, IL- 6 gene polymorphism, serum IL-6 and peripheral blood lymphocytes and monocytes with disease severity in COVID-19 patients

Coronavirus disease 2019 (COVID-19) is a fatal pandemic viral disease caused by the severe acute respiratory syndrome corona virus type-2 (SARS-CoV-2). The aim of this study is to observe the associations of IL-6, SARS-COV-2 viral load (RNAemia), IL- 6 gene polymorphism and lymphocytes and monocytes in peripheral blood with disease severity in COVID-19 patients. This study was carried out from March 2021 to January 2022. RT-PCR positive 84 COVID-19 patients and 28 healthy subjects were enrolled. Blood was collected to detect SARS-COV-2 viral RNA (RNAemia) by rRT-PCR, serum IL-6 level by chemiluminescence method, SNPs of IL-6 by SSP-PCR, immunophenotyping of lymphocytes and monocyte by flow cytometry. Serum IL-6 level (pg/ml) was considerably high among critical patients (102.02 +/- 149.7) compared to severe (67.20 +/- 129.5) and moderate patients (47.04 +/- 106.5) and healthy controls (3.5 +/- 1.8). Serum SARS-CoV-2 nucleic acid positive cases detected mostly in critical patients (39.28%) and was correlated with extremely high IL-6 level and high mortality (R =.912, P < 0.001). Correlation between IL-6 and monocyte was statistically significant with disease severity (severe group, p < 0.001, and 0.867*** and critical group p < 0.001 and 0.887***). In healthy controls, moderate, severe and critically ill COVID-19 patients, IL-6 174G/C (rs 1800795) GG genotype was 82.14%, 89.20%, 67.85% and 53.57% respectively. CC and GC genotype had strong association with severity of COVID-19 when compared with GG genotype. Significant statistical difference found in genotypes between critical and moderate groups (p < 0.001, OR-10.316, CI-3.22-23.86), where CC genotype was associated with COVID-19 severity and mortality. The absolute count of T cell, B cell, NK cell, CD4+ T cells and CD8+ T cells were significantly decreased in critical group compared to healthy, moderate and severe group (P < 0.001). Exhaustion marker CD94/NKG2A was increased on NK cells and CD8+ cytotoxic T cell among critical and severe group. Absolute count of monocyte was significantly increased in critical group (P < 0.001). Serum IL-6, IL-6 174 G/C gene and SARS-CoV-2 RNAaemia can be used in clinical practice for risk assessment;T cell subsets and monocyte as biomarkers for monitoring COVID-19 severity. Monoclonal antibody targeting IL-6 receptor and NKG2A for therapeutics may prevent disease progression and decrease morbidity and mortality.Copyright © 2023 Elsevier Inc.

Two-year outcome of extracorporeal membrane oxygenation in COVID-19 related severe respiratory failure

Objectives: We sought to evaluate 2-year outcome of V-V ECMO support for COVID-19 related severe respiratory failure in our center. Method(s): Retrospective analysis of 41 consecutive patients (73% male, mean age 51.6+/-14.2 years, mean BMI 35.1+/-12.5 kg/m2) with critical hypoxemic and/or hypercapnic refractory respiratory failure (mean P/F ratio 67.9+/-14.3 mmHg, mean pCO2 77.6.0+/-185.7 mmHg, Murray Score 3.71+/-0.4) on V-V ECMO support from October 2020 to January 2022 Results: With mean support duration of 234.4+/-63.2 hours, 29 patients (70.7%) were successfully weaned off. Finally, 19 of them (46.3%) were discharged home with good neurological outcome (CPC 1,2). During followup, 30-day, 6-, 12-, and 24 -month survival rate was 61.3%, 46.2%, 41.9%, and 41,9% respectively. In survivor group shorter symptoms onset to respiratory failure time (4+/-4.7 vs. 7+/-6.7 days, p=0.04), higher P/F ration (86+/-41.5 vs. 65+/-37.5 mmHg, p=0.04) and norepinephrine support (0.03+/-0.06 vs. 0.09+/-0.12 ug/kg/min, p=0.04), and lower IL-6 level (12.3+/-7.5 vs. 25.9+/-8.8 ng/l, p=0.03) p=0.01) were analysed before cannulation. Mean in-ICU stay and in-hospital stay in survivors;groups reached 32.5+/-27.7 days and 42.6+/-35.8 days, respectively. All long-term survivors (17 patients) complained about slight functional health limitation only with normal 6MWT (542.6+/- 89.2 min), near to normal spirometry parameters (FEV/VC 87+/-7.4%, DLCO 63.1+/-13.7%, KCO 82.,1+/-19.4%) and minimal neurological disability (CPC 1-2) Conclusion(s): 2-year outcome of V-V ECMO support in COVID-19 severe respiratory failure is acceptable even in the scope of low-volume ECMO centre. Reported functional status of long-term survivors was good despite the complicated and prolonged in-hospital stay. (Table Presented).

Clinical and laboratory indicators in predicting the risk of chronic heart failure in COVID-19 survivors.

Coronavirus disease has many systemic disease symptoms and has severe consequences for the cardiovascular system. Objective. To assess the role of clinical and laboratory indicators in determining the risk of chronic heart failure (CHF) in COV-ID-19 survivors. Material and methods. In total, 151 patients treated in a monoinfectious hospital from 03.11.20 to 10.02.21 with a confirmed diagnosis of COVID-19 were retrospectively selected. Medical history and laboratory data were collected by reviewing electronic medical records. The data included age, gender, body mass index, smoking status, and comorbidities. The laboratory data included the results of hematology and blood chemistry, coagulation, and the levels of acute-phase proteins. The CHF occurrence was used as the study endpoint. Results and discussion. The study patients were divided into two groups depending on the presence of CHF: group 1 included 46 patients with CHF, and group 2 included 105 patients without CHF. The median age was 66.2 (50-92) years;91 (60.3%) were females. Laboratory tests, such as levels of the hs-C-reactive protein, lactate dehydrogenase, procalcitonin, creatinine, and bilirubin, were statistically significantly different in patients of the study groups, and the median values were higher in patients with CHF. Neutrophil-lymphocyte ratio (NLR) showed statistically significant differences between groups: in patients with CHF, the median was 4.97% compared to 3.62% (p=0.011) in those without CHF. The most significant predictors of an increased risk of CHF were age >=66 years (OR=8.038, p<0.001), procalcitonin level >=0.09 ng/mL (increased the CHF risk by 3.8 times, p<0.001), thrombocy-topenia <=220x109/L (p=0.010), an NLR ratio >=4.11% (p=0.010), and a history of chronic kidney disease (p=0.018). Conclusion. A model has been developed to determine the factors closely associated with the risk of chronic heart failure in CO-VID-19 survivors.Copyright © 2023, Media Sphera Publishing Group. All rights reserved.

Mastocytosis and COVID19 infection and vaccination: A pediatric series

Introduction: Mastocytosis encompasses a heterogeneous group of diseases characterized by an accumulation of clonal mast cells (MC) in the skin and/or internal organs, and symptoms of MC activation. This MC activation can be elucidated by several factors, including infections or vaccination. Objective(s): We present our experience with COVID infection and vaccination in a series of 133 patients with pediatric mastocytosis. Method(s): Between January 1998 and December 2022, 133 pediatric patients have been referred to our hospital owing to clinically suspected MC disorder, mainly with mastocytosis in the skin. The final diagnoses of mastocytosis were established by the presence of typical skin lesions together with an increase of MC numbers in a biopsy from lesional skin or activating KIT mutations in lesional skin tissue. Serum baseline tryptase and total immunoglobulin E levels were measured, and patients underwent a comprehensive allergy workup to confirm atopic status and history of anaphylaxis. Regarding vaccination, REMA's (Spanish Network on Mastocytosis) protocol was followed. Result(s): 13 patients with COVID infection were identified, of which 25 (56,8%) were female and 0% had symptoms of MC activation. All of them had an asymptomatic or mild course of COVID infection. None of the patients experimented MC activation symptoms during viral illness. Regarding COVID vaccination, all patients received premedication with antihistamine 60 minutes prior vaccination. No one experimented immediate reactions and only one patient (0,75%) referred worsening of MC activation symptoms (baseline pruritus, urtication and brain fog) only after the first doses, recovering without changes in his treatment (oral cromoglycate and antihistamine) in two months. Discussion(s): Although MC have been implicated in the pathogenesis of cytokine storm in COVID19, there is no clinical evidence of SARSCoV- 2-induced MC activation, perhaps related to the fact that bone marrow MC lack angiotensin-converting enzyme 2 receptors.

GENE ANALYSIS REVEALED THE USEFULNESS OF TRIPLE THERAPY WITH BARICITINIB, RITUXIMAB AND TACROLIMS FOR ANTI-MDA5 ANTIBODY POSITIVE DERMATOMYOSITIS (MDA5-DM)

BackgroundAnti-MDA5 antibody positive dermatomyositis (MDA5-DM) is characterized by high mortality due to rapid progressive ILD. MDA5 is a cytosolic protein and a family of RIG-I like receptor, which functions as a virus RNA sensor and induces the production of such as type-1 IFN. Although little is known about the pathogenesis of MDA5-DM, it is notable that the similarities were reported between COVID-19 infection and MDA5-DM. It may suggest that there is a common underlying autoinflammatory mechanism. We reported that in MDA5-DM, (1) RIG-I-like receptor signaling is enhanced and (2) antiviral responses such as type 1 IFN signaling are also enhanced as compare with anti-ARS-antibody positive DM, and (3) the key for survival is suppression of RIG-I-like and IFN signaling (EULAR2022, POS0390). We also found that a significant role for uncontrolled macrophage in the pathogenesis of ILD by our autopsy case. Recently, it has been reported that tacrolimus (TAC) and cyclophosphamide (CY) combination therapy (TC-Tx) has improved the prognosis of cases with early onset of the disease, but there are cases that cannot be saved. Therefore, we devised BRT therapy (BRT-Tx). The Tx combines baricitinib (BAR), which inhibits GM-CSF and IFN-mediated signaling and effectively suppresses uncontrolled macrophages, with rituximab (RTX) and TAC, which rapidly inhibits B and T cell interaction and ultimately prevents anti-MDA5 antibody production.ObjectivesTo determine the differences in gene expression between BRT and TC-Tx for MDA5-DM in peripheral blood.MethodsTotal of 6 MDA5-DM (TC: 3, BRT: 3) were included and all of them had multiple poor prognostic factors. Peripheral whole blood was collected at just before and 2-3 months after the treatment. RNA was extracted, and quantified using a next-generation sequencer. Differentially Expressed Genes (DEGs) were identified by pre vs. post treatment. Gene Ontology (GO), clustering and Gene Set Variation Analysis (GSVA) were performed to DEGs. As one BRT case was added since our last year's report, we also reanalyzed the surviving vs. fatal cases. The IFN signature was scored separately for Types 1, 2, and 3, and the changes between pre- and post-treatment were investigated.ResultsTwo of three cases with TC died during treatment, while all three cases on BRT recovered. The cluster analysis of the DEGs separated deaths from survivors, not by type of treatment. Comparing surviving and dead cases, GO analysis revealed that the immune system via immunoglobulins and B cells was significantly suppressed in surviving cases. GO analysis of DEGs in each therapeutic group showed that expression of B cell-related genes such as lymphocyte proliferation and B cell receptor signaling pathway were significantly suppressed in BRT-Tx. On the other hand, TC-Tx significantly suppressed such pathways as cell proliferation and cell surface receptor signaling, and was less specific for the target cells than BRT-Tx. The changes in IFN signature score after treatment showed an increase in type 2 and 3 IFN scores in all fatal cases and an increase in type 1 IFN score in one fatal case.ConclusionBRT-Tx significantly suppressed gene expression associated with B cells, while TC-Tx was characterized by low specificity of therapeutic targets and suppression of total cell proliferation. Comparison of surviving and dead cases revealed that the combination of RTX contributed to the success of treatment, as suppression of the immune system mediated by immunoglobulins and B cells is the key for survival. Analysis of the IFN signature revealed an increase in IFN score after treatment in fatal cases, indicating that the combination of BAR is beneficial. The superiority of BRT-Tx seems clear from the fact that all patients survived with BRT-Tx while only one/three patients survived with TC-Tx.REFERENCES:NIL.Acknowledgements:NIL.Disclosure of InterestsMoe Sakamoto: None declared, Yu Nakai: None declared, Yoshiharu Sato: None declared, Yoshinobu Koyama Speakers bureau: Abbvie, Asahikasei, Ayumi, BMS, Esai, Eli-Lilly, Mitsubishi Tanabe, Grant/research support from: Abbvie, GSK.

Multi-objective Evolutionary Discretization of Gene Expression Profiles: Application to COVID-19 Severity Prediction

Machine learning models can use information from gene expressions in patients to efficiently predict the severity of symptoms for several diseases. Medical experts, however, still need to understand the reasoning behind the predictions before trusting them. In their day-to-day practice, physicians prefer using gene expression profiles, consisting of a discretized subset of all data from gene expressions: in these profiles, genes are typically reported as either over-expressed or under-expressed, using discretization thresholds computed on data from a healthy control group. A discretized profile allows medical experts to quickly categorize patients at a glance. Building on previous works related to the automatic discretization of patient profiles, we present a novel approach that frames the problem as a multi-objective optimization task: on the one hand, after discretization, the medical expert would prefer to have as few different profiles as possible, to be able to classify patients in an intuitive way;on the other hand, the loss of information has to be minimized. Loss of information can be estimated using the performance of a classifier trained on the discretized gene expression levels. We apply one common state-of-the-art evolutionary multi-objective algorithm, NSGA-II, to the discretization of a dataset of COVID-19 patients that developed either mild or severe symptoms. The results show not only that the solutions found by the approach dominate traditional discretization based on statistical analysis and are more generally valid than those obtained through single-objective optimization, but that the candidate Pareto-optimal solutions preserve the sense-making that practitioners find necessary to trust the results. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

Establishment of an infrastructure for rapid pandemic response at the Frederick National Laboratory

The sudden onset of the 2019 SARS-CoV-2 pandemic required agile development of standards and efficient validation of assays to assess prevalence of infection as well as immune responses to infection and vaccination. Leveraging their experience in HPV serology and standards, the Vaccine, Immunity and Cancer Directorate (VICD) at the Frederick National Laboratory for Cancer Research (FNCLR) pivoted to address this unmet need in SARS-Co-V2 serology clinical testing and research. This standardization effort required the collection and processing of large volumes of blood from SARS-Co-V2 infected and uninfected individuals into serum and peripheral blood mononuclear cells (PBMCs). Collaborations with specimen collection sites across the United States were established. Following qualification for anti-SARS-CoV-2 IgG and IgM levels in independent laboratories, VICD assembled reference evaluation panels, which were used to assist the FDA's performance evaluation of commercial assays submitted for EUA approval. To date, 185 different shipments of the standard or validation panel have been sent to both domestic and international labs. These materials are also available to the SARS-CoV-2 serology community for assay calibration and performance evaluation which greatly facilitates assay data harmonization. In addition, the NCI Serological Sciences Network (SeroNet) was born from this initiative and expertise, resulting in the establishment of Capacity Building Centers (CBCs) for sample collection from different healthy, cancer and immunocompromised cohorts at Mount Sinai, Arizona State University, the University of Minnesota, and Northwell Feinstein. The NCI and FNLCR simultaneously collaborated to develop a network of investigators focused on advancing research on the immune response to SARS-CoV-2 infection and vaccination among diverse and vulnerable populations, including cancer patients. Their research has resulted in over 326 peer-reviewed publications. The CBC's have enrolled patients in longitudinal studies, resulting in a centralized collection of annotated, well characterized serum, PBMCs and clinical data. Numerous cancer cohorts, but predominantly Multiple Myeloma, are included. Furthermore, technology development was supported at the CBC's. Based upon this success, the VICD in collaboration with NCI is pursuing an even more innovative effort in pandemic preparedness to establish a Center for Serology and Data Emergency Preparedness (CESDEP);a global network able to activate and pivot to address pandemic-level threats, while continuing to expand the development of immunological assays that can inform clinical decisions for cancer and other immunocompromised patients.

Hemoperfusion with CytoSorb as Adjuvant Therapy in Critically Ill Patients with SARS-CoV2 Pneumonia

Background: Several pro- and anti-inflammatory cytokines involved in COVID-19 and it is reasonable to speculate that their removal from blood might limit organ damage. Hemoperfusion with CytoSorb is a technique developed to adsorb molecules in the middle molecular weight range (up to 55 kDa). Studies in vitro and in vivo have shown that HP is highly effective in clearing blood from a number of cytokines. Method(s): We report a case series of 9 consecutive COVID-patients admitted to our COVID Intensive Care Unit (ICU). Five of them were treated with HP using CytoSorb (T), due to the heavy emergency overload it was impossible to deliver blood purification in the other 4 patients (C), who were also considered as potential candidates by the attending medical team. All patients had pneumonia and respiratory failure requiring continuous positive airway pressure. Different antibacterial prophylaxes, antiviral, and anti-inflammatory therapies including steroids were delivered. Result(s): Our results show a better clinical course of T compared to control patients (C), in fact all T except 1 survived, and only 2 of them were intubated, while all C required intubation and died. CRP decreased in both groups, but to a greater extent after HP. Lymphocytopenia worsened in control patient but not in treated patient after HP. Procalcitonin increased in 2 of the not treated patients. In all survived patients (n = 4) HP reduced pro-inflammatory cytokines, as IL-6, TNF-alpha, and IL-8. Notably, a striking effect was observed on IL-6 levels that at the end of the second session were decreased by a 40% than before the first treatment. Serum levels of IL-8 and TNF-alpha were lowered within normal range. In all patients the treatment was safe and there were no complications. Conclusion(s): Our study suggests a potential efficacy of HP in an early phase of viral infection not only for improving survival in the treated patients but also by the remodeling treatment-associated cytokine levels.

The immunopathology of COVID-19 placentitis: A multi-omic spatial approach

Problem: COVID-19 placentitis is a rare complication of maternal SARS-CoV-2 respiratory infection associated with serious adverse obstetric outcomes, including intra-uterine death. The precise role of SARS-CoV-2 in COVID-19 placentitis is uncertain, as trophoblast infection is only observed in around one-half of the affected placenta. Method of Study: Through multi-omic spatial profiling, including Nanostring GeoMX digital spatial profiling and Lunaphore COMET multiplex IHC, we provide a deep characterization of the immunopathology of placentitis from obstetrically complicated maternal COVID-19 infection. Result(s):We show that SARS-CoV-2 infection of placental trophoblasts is associated with a distinct innate and adaptive immune cell infiltrate, florid cytokine expression and upregulation of viral restriction factors. Quantitative spatial analyses reveal a unique microenvironment surrounding virus-infected trophoblasts characterizedd by multiple immune evasion mechanisms, including immune checkpoint expression, cytotoxic T-cell exclusion, and interferon blunting. Placental viral loads inversely correlated with the duration of maternal infection consistent with progressive virus clearance, potentially explaining the absence of virus in some cases. Conclusion(s): Our results demonstrate a central role for placental SARS-CoV-2 infection in driving the unique immunopathology of COVID-19 placentitis.

Determination of the Effects of Prenatal Remdesivir Exposure on Placenta Morphology, Placental IgG Transfer, and Fetal Growth in a Humanized Mouse Model

Remdesivir (RDV) is an antiviral medication used most recently for the treatment of COVID-19. Although no adverse effects were observed on perinatal parameters in reproductive and development toxicology studies at doses up to four-fold clinical area under the curve (AUC) exposures, some researchers have reported that therapeutic levels of RDV may impair early embryogenesis, as observed by in vitro studies. In addition, the influence of prenatal RDV exposure on maternal IgG transfer in the placenta is still unknown. Administration of RDV in pregnant humanized mouse model (Tg32), which expresses the human Fc gamma receptor and transporter (FCGRT) gene, was used to further evaluate potential effects on IgG transfer and concurrent perinatal endpoints. Animals were dosed daily from gestational days (GDs) 10- 14 with 25 mg/kg RDV (GS-5734) via intravenous injection (n=3-5 per group). Concurrent vehicle control animals were dosed intravenously with 12% sulfobutyl ether- beta-cyclodextrin in water (pH3.5;NaOH/HCl). All animals were administered 2 mg/kg human IgG via intravenous injection on GD 14. Placentae and fetuses were collected from dams on GD 14, 15, 16, and 18 and evaluated using histopathology and qPCR for inflammation markers. No abnormal morphologies (necrosis/apoptosis) of placentae were observed between the concurrent control and RDVdosed groups. Additionally, no differences in maternal body weights were observed. There were no statistically significant differences in placenta weights. There were no statistically significant changes in pregnancy parameters (implantation sites and dead fetuses/litter) and fetal weights between the RDV-dosed group and concurrent controls at GD 14, 15, 16, and 18. No changes were observed in transcript levels of inflammation markers in the RDV-dosed group when compared to the concurrent control group. There was a slightly lower ratio of fetal IgG level to maternal IgG levels in the RDV-dosed group;however, no statistically significant differences were observed between the RDV-dosed group and concurrent controls on GD 14, 15, 16, and 18. Our results suggest that a daily dose of 25 mg/kg RDV on GDs 10-14 in humanized mice did not cause adverse effects on placenta and fetal development. (Funded by the Perinatal Health Center of Excellence: E0300201.).

Newborn-onset chronic urticaria as the first manifestation of NLRP3 mosaicism

Objectives: A 7-month-old boy presented with generalized urticaria since the first week of life, without any other clinical manifestation. Cow's milk allergy was ruled out. His development was normal for his age. Maternal history was significant for COVID-19 infection in the third trimester of pregnancy with mild symptoms. Family history was significant for dermatographism in a maternal uncle. Hives were migratory with no single lesion persisting more than 24 h. There were no recognizable triggers and only relieved for 1-2 days after each vaccination. Patient was treated with optimal doses of antihistamines without improvement. Method(s): Laboratory tests and further studies were performed Results: Laboratory tests were normal including complete blood testing, circulating autoantibodies and infectious studies. C-reactive protein level and erythrocyte sedimentation rate were elevated. Due to chronic urticaria of newborn onset unresponsive to antihistamines a monogenic autoinflammatory disease was suspected. A targeted gene panel covering causative genes revealed the unreported p.Gly307Ala variant in the NLRP3 gene with a variant allele frequency (VAF) of 3% compatible with gene mosaicism. NLRP3 variant was classified as "likely pathogenic" based on its location, where a different variant has been reported as causing a severe form of cryopyrin-associated periodic syndromes (CAPS), and bioinformatic analyses. As expected, the variant was absent in patient's parents supporting for its de novo nature. Vision and hearing exams were normal. Treatment with canakinumab will start soon. Discussion(s): CAPS are dominantly-inherited autoinflammatory diseases caused by gain-of-function NLRP3 variants. These variants are often germline, but in some reported cases the variants are postzygotic causing gene mosaicism as in the patient here described. We believe that the mild presentation in our patient, despite having a likely pathogenic variant, may be explained by the low VAF. The genetic diagnosis in our patient allowed early initiation of anti-IL-1 treatment, which probably will prevent the development of other CAPS manifestations.

Boosting the Immune System with Vitamin D: Special Focus on Prevention of COVID-19 and Complications

In addition to the classical functions of the musculoskeletal system and calcium homeostasis, the function of vitamin D as an immune modulator is well established. The vitamin D receptors and enzymes that metabolize vitamin D are ubiquitously expressed in most cells in the body, including T and B lymphocytes, antigen-presenting cells, monocytes, macrophages and natural killer cells that trigger immune and antimicrobial responses. Many in vitro and in vivo studies revealed that vitamin D promotes tolerogenic immunological action and immune modulation. Vitamin D adequacy positively influences the expression and release of antimicrobial peptides, such as cathelicidin, defensin, and anti-inflammatory cytokines, and reduces the expression of proinflammatory cytokines. Evidence suggestss that vitamin D's protective immunogenic actions reduce the risk, complications, and death from COVID-19. On the contrary, vitamin D deficiency worsened the clinical outcomes of viral respiratory diseases and the COVID-19-related cytokine storm, acute respiratory distress syndrome, and death. The study revealed the need for more preclinical studies and focused on well-designed clinical trials with adequate sizes to understand the role of vitamin D on the pathophysiology of immune disorders and mechanisms of subduing microbial infections, including COVID-19.Copyright © 2023 Bentham Science Publishers.

The impact of deprivation on Respiratory Support Unit outcomes in COVID-19 patients, and highlights from wave 2 data in Portsmouth

Background: The second wave of the COVID-19 pandemic caused significant demand for beds capable of delivering enhanced respiratory support. NHS England recommended the use of CPAP for patients with COVID-19 respiratory failure, a treatment which can be offered outside of a critical care facility, and on a Respiratory High Care/ Support Unit (RSU). The enhancement of Portsmouth's RSU provided CPAP and NIV for patients with COVID-19 respiratory failure. With our intensive care facilities at 300% their normal capacity, this greatly alleviated bed pressures on critical care. Varied levels of deprivation exist in Portsmouth's dense population. Deprivation has an impact on overall health, however the effect of postcode on outcomes for people going onto support for COVID-19 respiratory failure, is unknown. Method(s): Retrospective cohort analysis of consecutive patients admitted to Respiratory Support Unit during the second wave of the COVID-19 pandemic, from 02/11/2020 to 31/01/2021. 227 patients were included in the study with 8 removed due to incomplete data, all of the patients received respiratory support in the form of CPAP or NIV. We collected multivariate data including biochemical markers, demographics, oxygenation status, co-morbidities and outcomes. Outcomes measured were: 1) Death in RSU, 2) Discharge from RSU or 3) Intubation and Ventilation. To measure deprivation, we linked a persons postcode to an area called an LSOA (Lower-layer Super Output Area). These are small areas of similar population size, each of which has a deprivation score (ie. top 10%, to the lowest 10% areas of deprivation in the UK). This is measured using an 'index of multiple deprivation'. An individual's outcome from the RSU was then analysed in relation to the deprivation score allocated to their postcode. Result(s): We observed a significant number of patients discharged from RSU, without needing invasive mechanical ventilation. 80/219 were discharged directly. 45/219 died in RSU, and 94 were eventually admitted to ITU. The average stay on CPAP or NIV before needing admission to ITU was 3 days. Some biochemical markers which stood out in relation to the outcomes described were as follows: average LDH, D-dimer and Troponin levels were higher in those who were admitted to intensive care. In patients who died, the PCT was significantly higher on average when compared to the other two groups. In the group who were discharged, mean lymphocyte count was >1, in the other two groups this was <1. From our observations in Portsmouth, there is a negative correlation between deprivation and lower aged individuals admitted for COVID-19 related respiratory support. Overall, we also saw disproportionate representation of those from the most deprived 50% of the UK in our respiratory support unit. Conclusion(s): CPAP and NIV can effectively be used in an RSU during a spike of COVID-19, to safely minimise demand on critical care services. Deprivation may have an impact on outcomes in patients needing respiratory support related to COVID-19. Deprivation levels may help predict risk of needing enhanced respiratory support in certain age groups. Multiple biochemical markers may be of prognostic value in COVID-19.

Potential role of Pancreatic Stone Protein (PSP) as early marker of bacterial infection in COVID-19 patients

Background: Sepsis is a life-threatening condition that needs immediate diagnosis and treatment to maximize the chances of survival. Bacterial superinfection is a severe and frequent complication among COVID-19 patients and its diagnosis is challenging. Previous reports suggested that Pancreatic Stone Protein (PSP) may be a predictive biomarker for sepsis in critically ill patients. We report a case series of three COVID- 19 patients admitted to our intensive care unit (ICU) with risk of sepsis. Method(s): We daily monitored PSP, procalcitonin (PCT), and C-reactive protein (CRP) levels in three COVID- 19 patients admitted to our ICU. Microbiological sampling and antibiotic treatment were performed according to the ward organization and in case of clinical suspects for infection. Positive cultures and antibiotic treatment were retrieved from clinical charts and patients were followed from ICU admission up to a maximum of 20 days. Result(s): Patient 1 (male, 55 years-old, overweight, no other comorbidity) was admitted to the ICU in treatment with Ceftriaxone then interrupted on day 7. On day 2 he was intubated and piperacillin/tazobactam was started on day 12 for suspected hospital acquired pneumonia. PSP levels markedly increased on day 10 with no significant changes in CRP and PCT levels. On day 13 a positive bronchospirate for Klebsiella pneumoniae was found. Similarly, patient 2 (male, 70 years-old, mild emphysema and diabetes) was admitted to ICU without antibiotic and with a PSP level of 287 ng/ml. His conditions rapidly worsened in severe septic shock requiring intubation. CRP markedly raised 48-72 hours after PSP with only mild increase of PCT. Patient 3 (male, 78 years-old, no comorbidities) was admitted to ICU with high levels of PSP and piperacillin/tazobactam therapy was started. After 48-72 hours CRP levels increased with no significant changes of PCT. A positive bronchospirate for Ps. aeruginosa was collected on day 3. Conclusion(s): Our findings suggest a potential role of PSP as early biomarker of sepsis in critically ill COVID-19 patients. Daily PSP monitoring may anticipate an appropriate treatment of COVID-19 patients with a septic complication in comparison with the actual laboratory markers. Further studies are needed to confirm our hypothesis.

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

The Impact of Covid19 Pandemic on Transfusion Dependent -Thalassemia Management: Experience of a Single Pediatric Treatment Center

Background: Health care systems have been facing COVID19 pandemic around the world for almost two years. Transfusion dependent (TDT) beta-thalassemia patients represent a vulnerable group,totally dependent upon hospital-based services. Aim(s): Aim of the present study was to evaluate the impact of COVID19 pandemic on management of TDT patients in a single pediatric treatment center in Northern Greece. Method(s): Patient records were reviewed in order to assess changes in management before and during the 24-month pandemic in Greece (03/01/2018-29/02/2020 and 03/01/2020 -28/02/2022, respectively) in terms of transfusion volume and transfusion frequency, mean value of pretransfusional hemoglobin, as well as laboratory parameters reflecting iron overload (ferritin levels, liver and heart MRI). Result(s): The study included 28 patients, 19 male (67.8%) and 9 female (32.2%), with an age range of 8 to 21 years. Mean number of hospital visits for transfusion was 19.97 +/- 3,52/ year prior to the pandemic and 22.38 +/- 4.35/year during the pandemic (p: 0.003). Average transfusion volume was 176.18ml +/- 38.32/kg/year kappaalphai 178.67 +/- 37.64ml/kg/year, respectively (p: 0.54). With regards to hemoglobin level, mean value was 9.56 +/- 0.42g/dl prior to the pandemic and 9.45 +/- 0.48gr/dl during the pandemic period. As to iron overload, mean ferritin level was 1362.05 +/- 517.56 ng/mL prior to the pandemic and 1021.27 +/- 508.92 ng/mL during the latter time period (p:0.016). Out of 28 enrolled patients, 26 underwent heart and liver MRI before pandemic and 23 during the pandemic period. Mean LIC values were 6.84 +/- 7.37 mg/gdw and 6.43 +/- 6.46 mg/gdw (p: 0.97) before and during the pandemic, respectively (p:0.97). Myocardial MRI values were within normal limits both before and during the pandemic. Summary-Conclusion: Covid19 pandemic did not seem to negatively affect the primary goal of transfusion therapy (pretransfusion Hb), even if an increased number of visits was required in order to transfuse the same blood volume - due to limited availability of blood units per visit. Of interest, pandemic conditions appeared to favor patient adherence to chelation therapy.