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Introduction Mutations in the IDH1 or IDH2 genes are detected in approximately 20% of cases of acute myeloid leukemia (AML). Few studies have examined the impact of IDH mutations in AML on allogeneic bone marrow transplant (alloBMT) outcomes. Patients and methods In this single center study, alloBMT outcomes for 61 patients with IDH-mutated (mIDH) AML were compared to those for 146 patients with IDH-wildtype (wtIDH) AML. Results Patients with mIDH AML had a 2-year overall survival (OS) of 85% (95% CI 76%-95%), 2-year relapse free survival (RFS) of 71% (95% CI 59%-85%), 1-year cumulative incidence of relapse (CIR) of 14% (95% CI 5%-23%) and a 1-year cumulative incidence of transplant related mortality (CITRM) of 3% (95% CI 0%-8%). Patients with wtIDH had a 2-year OS of 61% (95% CI 53%-70%), 2-year RFS of 58% (95% CI 50%-67%), 1-year CIR of 27% (95% CI 20%-35%), and a 1-year CITRM of 9% (95% CI 5%-14%). In a univariate analysis cox-proportional hazard model, mIDH was associated with significantly better OS (HR 0.52, 95% CI 0.29-0.96) and a trend toward better RFS (HR 0.60, 95% CI 0.35-1.01). After controlling for donor age, diagnosis, and ELN risk category, mIDH was associated with a nonsignificantly improved OS (HR 0.54, 95% CI 0.29-1.01) and RFS (HR 0.67, 95% CI 0.39-1.15). Conclusion Among patients with mIDH AML, patients who received a peritransplant IDH inhibitor had improved OS (P = .03) compared to those who did not, but there was no detectable difference for RFS (P = .29).

Agonist antibodies that activate cellular signaling have emerged as promising therapeutics for treating myriad pathologies. Unfortunately, the discovery of rare antibodies with the desired agonist functions is a major bottleneck during drug development. Nevertheless, there has been important recent progress in discovering and optimizing agonist antibodies against a variety of therapeutic targets that are activated by diverse signaling mechanisms. Herein, we review emerging high-throughput experimental and computational methods for agonist antibody discovery as well as rational molecular engineering methods for optimizing their agonist activity.

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) characterized by varying degrees of secondary neurodegeneration. Retinal ganglion cells (RGC) are lost in MS in association with optic neuritis but the mechanisms of neuronal injury remain unclear. Complement component C3 has been implicated in retinal and cerebral synaptic pathology that may precede neurodegeneration. Herein, we examined post-mortem MS retinas, and then used a mouse model, experimental autoimmune encephalomyelitis (EAE), to examine the role of C3 in the pathogenesis of RGC loss associated with optic neuritis. First, we show extensive C3 expression in astrocytes (C3(+)/GFAP(+) cells) and significant RGC loss (RBPMS(+) cells) in post-mortem retinas from people with MS compared to retinas from non-MS individuals. A patient with progressive MS with a remote history of optic neuritis showed marked reactive astrogliosis with C3 expression in the inner retina extending into deeper layers in the affected eye more than the unaffected eye. To study whether C3 mediates retinal degeneration, we utilized global C3(−/−) EAE mice and found that they had less RGC loss and partially preserved neurites in the retina compared with C3(+/+) EAE mice. C3(−/−) EAE mice had fewer axonal swellings in the optic nerve, reflecting reduced axonal injury, but had no changes in demyelination or T cell infiltration into the CNS. Using a C3-tdTomato reporter mouse line, we show definitive evidence of C3 expression in astrocytes in the retina and optic nerves of EAE mice. Conditional deletion of C3 in astrocytes showed RGC protection replicating the effects seen in the global knockouts. These data implicate astrocyte C3 expression as a critical mediator of retinal neuronal pathology in EAE and MS, and are consistent with recent studies showing C3 gene variants are associated with faster rates of retinal neurodegeneration in human disease.

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS), characterized by demyelination, gliosis, and neurodegeneration. While the currently available disease-modifying therapies effectively suppress the immune attack on the CNS, there are no therapies to date that directly mitigate neurodegeneration. Glucagon-like peptide-1 (GLP-1) is a small peptide hormone that maintains glucose homeostasis. A novel GLP-1 receptor (GLP-1R) agonist, NLY01, was recently shown to have neuroprotective effects in the animal models of Parkinson’s disease and is now in a phase 2 clinical trial. In this study, we investigated the therapeutic potential of NLY01 in a mouse model of MS, experimental autoimmune encephalomyelitis (EAE). Our data show that NLY01 delays the onset and attenuates the severity of EAE in a prevention paradigm, when given before disease onset. NLY01 inhibits the activation of immune cells in the spleen and reduces their trafficking into the CNS. In addition, we show that NLY01 suppresses the production of chemokines that are involved in leukocyte recruitment to the site of inflammation. The anti-inflammatory effect of NLY01 at the early stage of EAE may block the expression of the genes associated with neurotoxic astrocytes in the optic nerves, thereby preventing retinal ganglion cell (RGC) loss in the progressive stage of EAE. In the therapeutic paradigm, NLY01 significantly decreases the clinical score and second attack in a model of relapsing–remitting EAE. GLP-1R agonists may have dual efficacy in MS by suppressing peripheral and CNS inflammation, thereby limiting neuronal loss. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13311-021-01088-5.

Objective The goal of this exploratory study was to evaluate the effects of an exercise intervention – progressive resistance training (PRT) on the metabolome of people with MS (pwMS) and to link these to changes in clinical outcomes. Methods 14 pwMS with EDSS

Assessment of patient out-of-pocket cost for palbociclib therapy in advanced breast cancerBackground:Palbociclib has demonstrated improved outcomes in patients with advanced hormone receptor positive (HR+)/human epidermal growth factor 2 (HER2) negative breast cancer when used in combination with endocrine therapy 1,2. The current average wholesale price of therapy with this medication class exceeds $190,000 per year (at full dose). Financial toxicity is a major concern in the oncology population and can decrease patient quality of life and may result in non-adherence 3,4. Our objective was to describe the out-of-pocket cost burden for patients treated with palbociclib. Methods:A retrospective review of patients newly initiated on palbociclib therapy between May 5, 2018 and May 30, 2019 was completed at our institution. Patients were included if they were 18 years of age and older, newly starting palbociclib for advanced or metastatic HR+/HER2- breast cancer, had US-based insurance, and received palbociclib from our internal specialty pharmacy. Cost information was collected utilizing dispensing reports and additional patient-specific information was obtained from the EHR. Descriptive statistics were performed on the collected data. Results:A total of 44 patients were included in the cost analysis. Primary sources of coverage for these patients included commercial insurance (n=13), Medicare (n=25), and state/federal insurance (n=6). We first assessed costs with primary insurance coverage alone. The sum of all the initial cycle out-of-pocket copays after primary insurance totaled $49,108. The median individual copay was $291, the range was $0 to $2,943, and 9 of the 44 patients had no copay after the primary insurance was applied. The impact of assistance programs, which include independent grant funding, copay cards, vouchers, and secondary Medicaid plans, was significant. After applying primary insurance and aid from assistance programs, the sum of all initial cycle out-of-pocket copays reduced from $49,108 to $3,172. After assistance, 33 of the 44 patients had an initial copay cost of $0. Over 90% of the out-of-pocket total was from two patients (one each with a copay of $2,467 and $497). Ultimately, Mayo Clinic Specialty Pharmacy helped patients avoid $45,851 in first cycle out-of-pocket copays, of which $41,079 and $4,772 were for Medicare and commercially-insured patients, respectively. Copay cost by type of insurance was assessed. All patients with commercial insurance (n=13) had no actual copay for the first cycle. Medicare patients (n=25) are not eligible for copay cards and had larger pre-assistance copays compared to commercial patients (median $2,454 vs. $45). Vouchers or grants were utilized by 16 out of 25 Medicare covered patients. State/Federal insurance included 2 Tricare and 4 Medicaid patients. While ineligible for copay card assistance, the copays for these patients were low, ranging from $0-$28. Standard Medicare D plans do not have an out of pocket maximum for the year. The catastrophic phase requires an ongoing copay of 5% of the total claim cost, resulting in approximately a $600 per month copay for the remainder of the calendar year during the study period. When combined with the first cycle cost of approximately $2500, the yearly out-of-pocket cost for a patient with a standard Medicare D plan is roughly $10,000. Conclusion:Patients initiating therapy with palbociclib are commonly faced with high out-of-pocket costs. The availability, eligibility, and use of financial assistance programs are imperative in decreasing the financial toxicity. Specialty pharmacies play an important role in obtaining financial assistance which leads to decreased out-of-pocket expenses for patients. Citation Format: Allison P Golbach, Matthew D Smith, Jodi L Taraba, Karthik V Giridhar. Assessment of patient out-of-pocket cost for palbociclib therapy in advanced breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS7-49.

CD138 magnetic sorting impacts the phenotypic characteristics of myeloma plasma cells. In our evaluation of bone marrow aspirates from 16 patients, we observed complete loss or under expression of cell surface antigens by CD138-positive sorting as compared with whole bone marrow lyse and wash method. This should be kept in mind when designing studies for diagnosis and treatment of multiple myeloma. BACKGROUND: Isolation of malignant plasma cells from bone marrow of patients with monoclonal gammopathies is critical for studies into the disease biology. The plasma cells are typically isolated by positive selection using plasma cell markers such as CD138. Here we have examined the effect of CD138 magnetic bead selection on the expression of other surface phenotypic markers on plasma cells. MATERIALS AND METHODS: Bone marrow aspirates from 16 patients were split and prepared using 2 methods before staining for flow cytometric evaluation. The first method (whole bone marrow) used an ammonium-chloride-potassium lyse of whole bone marrow followed by 2 phosphate buffered saline washes. The second method used CD138-positive magnetic sorting technology (Stem Cell Technology). The cells were run on the FACSCanto flow cytometer after staining for CD38, CD45, CD56, activation markers CD71, CD69, CD154, adhesion markers CD49d, CD49e, CD11a, CD11b, and CD66, B cell markers CD19 and CD20, and for clonality. RESULTS: There was a substantial loss in the expression of CD71, CD11b, CD11a, CD69, and CD49e on plasma cells following CD138-based sorting. Moreover, in 8 of the 16 cases, there was a nearly complete loss of the CD45-positive subset with a loss of discrimination between CD45-negative and CD45-positive plasma cell subsets in the remaining CD138-sorted preparations. CONCLUSIONS: The change in immunophenotype of the plasma cells on magnetic sorting should be kept in mind when isolating plasma cells using CD138-positive selection for analysis of plasma cells. The technique for characterizing plasma cells should be selected based on the study design to prevent loss of crucial and valuable information.

The timing of reproduction is often governed by environmental variables, such as temperature or rainfall. Understanding how environmental variables affect mating dynamics is necessary to predict how systems and populations may adapt to changing environmental conditions and is crucial for management of threatened species. The American horseshoe crab (Limulus polyphemus) ranges from the Yucatan to Maine in distinct populations that differ in their timing of reproduction; while most populations have only one breeding period during the spring, some southern populations have two breeding periods. Here we discuss seasonal patterns of reproduction in a Florida Gulf coast population where horseshoe crabs have two periods of breeding: one in the spring and another in the fall. We used environmental measurements, spawning surveys, mark-recapture, and measurements of adult traits and spawning behavior to compare reproductive parameters between the two spawning seasons over three years. We then evaluated whether environmental conditions affect fall and spring horseshoe crab nesting patterns similarly and whether fall and spring horseshoe crabs should be considered two separate populations. We found significant differences in environmental conditions across seasons and in a wide variety of horseshoe crab traits and nesting parameters. Furthermore, environmental conditions affected nesting behaviors of fall and spring horseshoe crabs differently. However, some individuals spawn during both seasons, suggesting that trait differences may be attributable to environmental effects during development or seasonal plasticity, rather than genetic differences, although further study is necessary. Finally, our results suggest that management practices should be tailored to each population, because environmental conditions may have different effects even on genetically similar groups.

The ability of antibodies to recognize their target antigens with high specificity is fundamental to their natural function. Nevertheless, therapeutic antibodies display variable and difficult-to-predict levels of non-specific and self-interactions that can lead to various drug development challenges, including antibody aggregation, abnormally high viscosity and rapid antibody clearance. Here we report a method for predicting the overall specificity of antibodies in terms of their relative risk for displaying high levels of non-specific and/or self-interactions at physiological conditions. We find that individual and combined sets of chemical rules that limit the maximum and minimum numbers of certain solvent-exposed residues in antibody variable regions are strong predictors of specificity for large panels of preclinical and clinical-stage antibodies. We also demonstrate how the chemical rules can be used to identify sites that mediate non-specific interactions in suboptimal antibodies and guide the design of targeted sub-libraries that yield variants with high antibody specificity. These findings can be readily used to improve the selection and engineering of antibodies with drug-like specificity.

Background Atypical femur fracture (AFF) is a clinically important complication of bisphosphonate (BP) use in the treatment of osteoporosis. The benefits of long-term BP therapy in preventing osteoporotic fractures have been shown to outweigh the risks of treatment. Discontinuation of BPs or “drug holidays” have been implemented as a strategy to reduce the risk of rare complications such as AFF. Case report We present the case of a 70-year-old postmenopausal woman who suffered bilateral AFF ten years after discontinuation of BP treatment. Management of this patient included fixation of the complete AFF with an intramedullary rod. A single dose of denosumab was administered prior to referral to endocrinology and seemed to contribute to callus formation. Denosumab was discontinued to prevent progression of the contralateral incomplete AFF. Teriparatide was indicated for the treatment of this patient's osteoporosis and also led to the resolution of the incomplete AFF. Conclusion Patients receiving long-term BP therapy should be periodically reevaluated in order to maximize the benefit and minimize the risk of treatment. Current research supports the implementation of drug holidays to decrease the risk of AFF; however, this case report confirms the need for continued monitoring after discontinuation of BP therapy. Additionally, our review of current literature highlights the need for more specific research regarding duration of BP treatment and drug holidays., Highlights • This patient presented with bilateral AFF ten years after the last dose of bisphosphonates. • Denosumab was used in the treatment of the complete AFF with good callus formation. • Teriparatide led to the resolution of the incomplete AFF after three months of treatment.

Background: Sphingosine-1-phosphate receptor (S1P) modulators and anti-CD20 therapies impair humoral responses to SARS-CoV-2 mRNA vaccines. Relatively few studies have assessed the impact of an array of disease modifying therapies (DMTs) for multiple sclerosis (MS) on T cell immune responses to SARS-CoV-2 vaccination. Methods: In 101 people with MS, we measured humoral responses via an immunoassay to measure IgG against the COVID-19 spike S1 glycoprotein in serum. We also measured T cell responses using FluoroSpot assay for interferon gamma (IFN-γ) (Mabtech, Sweden) using cryopreserved rested PBMCs and then incubated in cRPMI with 1µg/ml of pooled peptides spanning the entire spike glycoprotein (Genscript, 2 pools; 158 peptides each). Plates were read on an AID iSpot Spectrum to determine the number of spot forming cells (SFC)/106 PBMCs. We tested for differences in immune responses across DMTs using linear models. Findings: Humoral responses were detected in 22/39 (56.4%) participants on anti-CD20 and in 59/63 (93.6%) participants on no or other DMTs. In a subset (n=88; 87%), T cell responses were detected in 76/88 (86%), including 32/33 (96.9%) participants on anti-CD20 therapies. Anti-CD20 therapies were associated with an increase in IFN-γ SFC counts relative to those on no DMT or other DMTs (for anti-CD20 vs. no DMT: 425.9% higher [95%CI: 109.6%, 1206.6%] higher; p

Multiple sclerosis (MS) lesions that do not resolve in the months after they form harbour ongoing demyelination and axon degeneration, and are identifiable in vivo by their paramagnetic rims on MRI scans1-3. Here, to define mechanisms underlying this disabling, progressive neurodegenerative state4-6 and foster development of new therapeutic agents, we used MRI-informed single-nucleus RNA sequencing to profile the edge of demyelinated white matter lesions at various stages of inflammation. We uncovered notable glial and immune cell diversity, especially at the chronically inflamed lesion edge. We define 'microglia inflamed in MS' (MIMS) and 'astrocytes inflamed in MS', glial phenotypes that demonstrate neurodegenerative programming. The MIMS transcriptional profile overlaps with that of microglia in other neurodegenerative diseases, suggesting that primary and secondary neurodegeneration share common mechanisms and could benefit from similar therapeutic approaches. We identify complement component 1q (C1q) as a critical mediator of MIMS activation, validated immunohistochemically in MS tissue, genetically by microglia-specific C1q ablation in mice with experimental autoimmune encephalomyelitis, and therapeutically by treating chronic experimental autoimmune encephalomyelitis with C1q blockade. C1q inhibition is a potential therapeutic avenue to address chronic white matter inflammation, which could be monitored by longitudinal assessment of its dynamic biomarker, paramagnetic rim lesions, using advanced MRI methods.

OBJECTIVES The ability to accurately estimate the risk of peri-operative mortality after lung resection is important. There are concerns about the performance and validity of existing models developed for this purpose, especially when predicting mortality within 90 days of surgery. The aim of this study was therefore to develop a clinical prediction model for mortality within 90 days of undergoing lung resection. METHODS A retrospective database of patients undergoing lung resection in two UK centres between 2012 and 2018 was used to develop a multivariable logistic risk prediction model, with bootstrap sampling used for internal validation. Apparent and adjusted measures of discrimination (area under receiving operator characteristic curve) and calibration (calibration-in-the-large and calibration slope) were assessed as measures of model performance. RESULTS Data were available for 6600 lung resections for model development. Predictors included in the final model were age, sex, performance status, percentage predicted diffusion capacity of the lung for carbon monoxide, anaemia, serum creatinine, pre-operative arrhythmia, right-sided resection, number of resected bronchopulmonary segments, open approach and malignant diagnosis. Good model performance was demonstrated, with adjusted area under receiving operator characteristic curve, calibration-in-the-large and calibration slope values (95% confidence intervals) of 0.741 (0.700, 0.782), 0.006 (−0.143, 0.156) and 0.870 (0.679, 1.060), respectively. CONCLUSIONS The RESECT-90 model demonstrates good statistical performance for the prediction of 90-day mortality after lung resection. A project to facilitate large-scale external validation of the model to ensure that the model retains accuracy and is transferable to other centres in different geographical locations is currently underway.

Gait dysfunction is a key defining feature of Parkinson’s disease (PD), and is associated with symptoms of freezing and an increased risk of falls. In this narrative review, we cover the putative mechanisms of gait dysfunction in PD, the assessment of gait abnormalities, and the management of symptoms caused by the inherent difficulty in walking. Our understanding of the causes of gait problems in PD has progressed in recent times, moving from neurocognitive theory to correlates of affected neuronal pathways. In particular, this can be shown to correspond with abnormalities in responses to dual-task paradigms and dysfunction in cholinergic signaling. Great progress has been made in the sophistication and precision of gait assessment; however, it has firmly remained in the research domain. There is significant momentum behind wearable technologies that can be used by patients in their own environment, acting as digital biomarkers that can not only reflect progression but also independently discriminate PD from non-PD individuals. The treatment of gait dysfunction has historically relied on physical therapies and training combined with a view to mitigating the impact of such consequences as falls. Pharmacological therapies that are the mainstay of treatment in PD have tended to address symptoms like bradykinesia; however, optimization of dopaminergic therapies likely has a positive effect on quality of gait. Other targets have been assessed with the goal of improving gait, of which medications that improve cholinergic signaling appear most promising. Neuromodulation techniques are increasingly used in the form of deep-brain stimulation; however, standard targets, such as the globus pallidus interna, have a modest effect on gait. Considerable benefit has been seen through targeting the pedunculopontine nucleus, and a dual-target approach may be warranted. Stimulation of the spinal cord and brain through direct or magnetic approaches has been assessed, but requires further evidence.

Loss-of-function mutations in genes encoding TET DNA dioxygenase occur frequently in hematopoietic malignancy, but rarely in solid tumors, which instead commonly have reduced activity. The impact of decreased TET activity in solid tumors is not known. Here we show that TET2 mediates the IFN-γ/JAK/STAT signaling pathway to control chemokine and PD-L1 expression, lymphocyte infiltration, and cancer immunity. IFN-γ stimulated STAT1 to bind TET2 and recruit TET2 to hydroxymethylate chemokine and PD-L1 genes. Reduced TET activity was associated with decreased Th1-type chemokines and tumor-infiltrating lymphocytes and the progression of human colon cancer. Deletion of Tet2 in murine melanoma and colon tumor cells reduced chemokine expression and tumor-infiltrating lymphocytes, enabling tumors to evade antitumor immunity and to resist anti–PD-L1 therapy. Conversely, stimulating TET activity by systematic injection of its cofactor ascorbate/vitamin C increased chemokines and tumor-infiltrating lymphocytes, leading to enhanced antitumor immunity and anti–PD-L1 efficacy and extended lifespan of tumor-bearing mice. These results suggest an IFN-γ/JAK/STAT/TET signaling pathway that mediates tumor response to anti–PD-L1/PD-1 therapy and is frequently disrupted in solid tumors. Our findings also suggest TET activity as a biomarker for predicting the efficacy of and patient response to anti–PD-1/PD-L1 therapy, and stimulation of TET activity as an adjuvant immunotherapy of solid tumors.

Multiple sclerosis is a heterogeneous disease with an unpredictable course and a wide range of severity; some individuals rapidly progress to a disabled state whereas others experience only mild symptoms. Though genetic studies have identified variants that are associated with an increased risk of developing multiple sclerosis, no variants have been consistently associated with multiple sclerosis severity. In part, the lack of findings is related to inherent limitations of clinical rating scales; these scales are insensitive to early degenerative changes that underlie disease progression. Optical coherence tomography imaging of the retina and low-contrast letter acuity correlate with and predict clinical and imaging-based outcomes in multiple sclerosis. Therefore, they may serve as sensitive phenotypes to discover genetic predictors of disease course. We conducted a set of genome-wide association studies of longitudinal structural and functional visual pathway phenotypes in multiple sclerosis. First, we assessed genetic predictors of ganglion cell/inner plexiform layer atrophy in a discovery cohort of 374 patients with multiple sclerosis using mixed-effects models adjusting for age, sex, disease duration, optic neuritis and genetic ancestry and using a combination of single-variant and network-based analyses. For candidate variants identified in discovery, we conducted a similar set of analyses of ganglion cell/inner plexiform layer thinning in a replication cohort (n = 376). Second, we assessed genetic predictors of sustained loss of 5-letters in low-contrast letter acuity in discovery (n = 582) using multivariable-adjusted Cox proportional hazards models. We then evaluated candidate variants/pathways in a replication cohort. (n = 253). Results of both studies revealed novel subnetworks highly enriched for connected genes in early complement activation linked to measures of disease severity. Within these networks, C3 was the gene most strongly associated with ganglion cell/inner plexiform layer atrophy (P = 0.004) and C1QA and CR1 were top results in analysis of sustained low-contrast letter acuity loss. Namely, variant rs158772, linked to C1QA, and rs61822967, linked to CR1, were associated with 71% and 40% increases in risk of sustained LCLA loss, respectively, in meta-analysis pooling discovery and replication cohorts (rs158772: hazard ratio: 1.71; 95% confidence interval 1.30–2.25; P = 1.3 × 10−4; rs61822967: hazard ratio: 1.40; 95% confidence interval: 1.16–1.68; P = 4.1 × 10−4). In conclusion, early complement pathway gene variants were consistently associated with structural and functional measures of multiple sclerosis severity. These results from unbiased analyses are strongly supported by several prior reports that mechanistically implicated early complement factors in neurodegeneration.

Background Leptomeningeal inflammation is associated with increased cortical damage and worse clinical outcomes in MS. It may be detected on contrast-enhanced T2-FLAIR imaging as focal leptomeningeal contrast-enhancement (LME). Objective To assess the safety of intrathecal (IT) rituximab in progressive MS (PMS) and to assess its effects on LME and CSF biomarkers. Methods PMS patients had a screening MRI to detect LME. Participants satisfying eligibility criteria underwent two IT administrations of 25 mg rituximab 2 weeks apart. Follow-up lumbar puncture and MRI were performed at 8 and 24 weeks after the first treatment. Results Of 36 patients screened 15 had LME, 11 consented, and 8 received study treatment. Mean age was 56.7 years and number of LME lesions ranged from 1 to 3. No serious adverse effects occurred. We noted profound reductions in peripheral B cells from baseline to week 2 and 8 with some return at week 24. We also observed transient reductions in CSF B cells and CXCL-13 levels with an increase in BAFF levels. However, the number of LME did not change following treatment. Conclusions IT rituximab was well tolerated in PMS patients and had transient effects on CSF biomarkers but did not change LME.

While neuroinflammation is an evolving concept and the cells involved and their functions are being defined, microglia are understood to be a key cellular mediator of brain injury and repair. The ability to measure microglial activity specifically and noninvasively would be a boon to the study of neuroinflammation, which is involved in a wide variety of neuropsychiatric disorders including traumatic brain injury, demyelinating disease, Alzheimer’s disease (AD), and Parkinson’s disease, among others. We have developed [(11)C]CPPC [5-cyano-N-(4-(4-[(11)C]methylpiperazin-1-yl)-2-(piperidin-1-yl)phenyl)furan-2-carboxamide], a positron-emitting, high-affinity ligand that is specific for the macrophage colony-stimulating factor 1 receptor (CSF1R), the expression of which is essentially restricted to microglia within brain. [(11)C]CPPC demonstrates high and specific brain uptake in a murine and nonhuman primate lipopolysaccharide model of neuroinflammation. It also shows specific and elevated uptake in a murine model of AD, experimental allergic encephalomyelitis murine model of demyelination and in postmortem brain tissue of patients with AD. Radiation dosimetry in mice indicated [(11)C]CPPC to be safe for future human studies. [(11)C]CPPC can be synthesized in sufficient radiochemical yield, purity, and specific radioactivity and possesses binding specificity in relevant models that indicate potential for human PET imaging of CSF1R and the microglial component of neuroinflammation.

Tail-anchored (TA) proteins are a unique class of integral membrane proteins that possess a single C-terminal transmembrane domain and target post-translationally to the specific organelles at which they function. While significant advances have been made in recent years in elucidating the mechanisms and molecular targeting signals involved in the proper sorting of TA proteins, particularly to the endoplasmic reticulum and mitochondria, relatively little is known about the targeting of TA proteins to the plastid outer envelope. Here we show that several known or predicted plastid TA outer envelope proteins (OEPs) in Arabidopsis possess a C-terminal RK/ST sequence motif that serves as a conserved element of their plastid targeting signal. Evidence for this conclusion comes primarily from experiments with OEP7.2, which is a member of the Arabidopsis 7 kDa OEP family. We confirmed that OEP7.2 is localized to the plastid outer envelope and possesses a TA topology, and its C-terminal sequence (CTS), which includes the RK/ST motif, is essential for proper targeting to plastids. The CTS of OEP7.2 is functionally interchangeable with the CTSs of other TA OEPs that possess similar RK/ST motifs, but not with those that lack the motif. Further, a bioinformatics search based on a consensus sequence led to the identification of several new OEP TA proteins. Collectively, this study provides new insight into the mechanisms of TA protein sorting in plant cells, defines a new targeting signal element for a subset of TA OEPs and expands the number and repertoire of TA proteins at the plastid outer envelope.

Although some evidence to suggest an association between preoperative anemia and reduced overall survival exists, contemporary studies investigating the impact of preoperative anemia on outcomes after resection for primary lung cancer are lacking.A multicenter retrospective review.Two tertiary cardiothoracic surgery centers in the Northwest of England.A total of 5,029 patients between 2012 and 2018.All patients underwent lung resection for primary lung cancer. Patients were classified as anemic based on the World Health Organization definition. Men with hemoglobin130 g/L and women with hemoglobin120 g/L were considered to be anemic.Outcomes assessed included perioperative mortality, 90-day mortality, and overall survival. Multivariate logistic and Cox regression analyses were used to assess the impact of preoperative anemia on 90-day mortality and overall survival, respectively. Overall, preoperatively, 24.0% (n = 1207) of patients were anemic. The 90-day mortality for anemic and nonanemic patients was 5.6% and 3.1%, respectively (p0.001). After multivariate adjustment, preoperative anemia was not associated with increased 90-day mortality. However, a log-rank analysis demonstrated reduced overall survival for anemic patients (p0.001). After multivariate adjustment, preoperative anemia was found to be independently associated with reduced overall survival (hazard ratio 1.287, 95% confidence interval 1.141-1.451, p0.001).Although anemia was not an independent predictor of short-term outcomes, it was independently associated with significantly reduced survival for patients undergoing resection for lung cancer. Further work is required to understand why anemia reduces long-term survival and whether pathways for anemic patients can be adapted to improve long-term outcomes.

The COVID‐19 pandemic continues to be a severe threat to human health, especially due to current and emerging SARS‐CoV‐2 variants with potential to escape humoral immunity developed after vaccination or infection. The development of broadly neutralizing antibodies that engage evolutionarily conserved epitopes on coronavirus spike proteins represents a promising strategy to improve therapy and prophylaxis against SARS‐CoV‐2 and variants thereof. Herein, a facile multivalent engineering approach is employed to achieve large synergistic improvements in the neutralizing activity of a SARS‐CoV‐2 cross‐reactive nanobody (VHH‐72) initially generated against SARS‐CoV. This synergy is epitope specific and is not observed for a second high‐affinity nanobody against a non‐conserved epitope in the receptor‐binding domain. Importantly, a hexavalent VHH‐72 nanobody retains binding to spike proteins from multiple highly transmissible SARS‐CoV‐2 variants (B.1.1.7 and B.1.351) and potently neutralizes them. Multivalent VHH‐72 nanobodies also display drug‐like biophysical properties, including high stability, high solubility, and low levels of non‐specific binding. The unique neutralizing and biophysical properties of VHH‐72 multivalent nanobodies make them attractive as therapeutics against SARS‐CoV‐2 variants., This work reports a multivalent engineering strategy to synergistically increase the neutralization potency of nanobodies against SARS‐CoV‐2. An engineered hexavalent nanobody directed against an evolutionarily conserved epitope potently neutralizes SARS‐CoV‐2 and two key variants of concern (B.1.1.7 and B.1.351). This facile approach significantly improves the neutralization breadth and potency of promising nanobodies for potential use in therapeutic applications.

Injury and loss of oligodendrocytes can cause demyelinating diseases such as multiple sclerosis. To improve our understanding of human oligodendrocyte development, which could facilitate development of remyelination-based treatment strategies, here we describe time-course single-cell-transcriptomic analysis of developing human stem cell-derived oligodendrocyte-lineage-cells (hOLLCs). The study includes hOLLCs derived from both genome engineered embryonic stem cell (ESC) reporter cells containing an Identification-and-Purification tag driven by the endogenous PDGFRα promoter and from unmodified induced pluripotent (iPS) cells. Our analysis uncovers substantial transcriptional heterogeneity of PDGFRα-lineage hOLLCs. We discover sub-populations of human oligodendrocyte progenitor cells (hOPCs) including a potential cytokine-responsive hOPC subset, and identify candidate regulatory genes/networks that define the identity of these sub-populations. Pseudotime trajectory analysis defines developmental pathways of oligodendrocytes vs astrocytes from PDGFRα-expressing hOPCs and predicts differentially expressed genes between the two lineages. In addition, pathway enrichment analysis followed by pharmacological intervention of these pathways confirm that mTOR and cholesterol biosynthesis signaling pathways are involved in maturation of oligodendrocytes from hOPCs., Brain myelinating oligodendrocytes are rare and difficult to isolate, which has limited data on their development. Here the authors develop a reporter for scalable purification of human pluripotent stem cell derived oligodendrocyte lineage cells, and use this to map differentiation using single cell RNA-sequencing

The circulating metabolome is a product of interactions between the genome, epigenome, exposome and microbiome. The metabolome may be altered in people with multiple sclerosis (MS); however, existing metabolomics studies were relatively small or characterized a limited number of metabolites. Herein, we performed a multi-site study profiling the circulating metabolome to obtain relative abundances for 269 metabolites in a large cohort of MS patients and healthy controls. After adjusting for batch effects and extensive quality control, we created an overall metabolic dysfunction score, defined apriori sets of metabolites using known metabolic pathways, and derived novel networks of correlated metabolites using a weighted correlation network analysis (WGCNA). We assessed whether metabolic dysfunction, individual metabolites, metabolic pathways or WGCNA-identified module scores differed between people with MS versus healthy controls (HC) after adjusting for age, sex and race using generalized estimating equations (participants could provide multiple samples). In a subset of patients, information on disability status was also available. Similar models assessed the association between metabolites and metabolite sets with measures of disability. In people with MS, we identified striking abnormalities in a WGCNA-defined module enriched in aromatic amino acid (AAA) metabolites (FDR-adjusted p-value=2.77E-18) that are also strongly associated with disability (FDR-adjusted p-value for AAA module=1.01E-4). Consistent results were obtained using apriori-defined metabolite sets or in analyses of individual metabolites. The identified abnormalities likely relate to imbalances in gut microbial metabolism of AAAs resulting in reduced production of immunomodulatory metabolites and increased production of metabotoxins (indole acetate, phenylacetylglutamine, p-cresol sulfate, p-cresol glucuronide). Single cell RNA sequencing data analysis demonstrated altered AAA metabolism in CSF and blood derived monocyte cell populations, while treatment of human peripheral blood mononuclear cells with AAA-derived metabotoxins resulted in increased production of tumor necrosis factor-α. We identify novel metabolic alterations in people with MS potentially contributing to disease pathophysiology.

The aggregation of amyloidogenic polypeptides is strongly linked to several neurodegenerative disorders, including Alzheimer's and Parkinson's diseases. Conformational antibodies that selectively recognize protein aggregates are leading therapeutic agents for selectively neutralizing toxic aggregates, diagnostic and imaging agents for detecting disease, and biomedical reagents for elucidating disease mechanisms. Despite their importance, it is challenging to generate high-quality conformational antibodies in a systematic and site-specific manner due to the properties of protein aggregates (hydrophobic, multivalent, and heterogeneous) and limitations of immunization (uncontrolled antigen presentation and immunodominant epitopes). Toward addressing these challenges, we have developed a systematic directed evolution procedure for affinity maturing antibodies against Alzheimer's Aβ fibrils and selecting variants with strict conformational and sequence specificity. We first designed a library based on a lead conformational antibody by sampling combinations of amino acids in the antigen-binding site predicted to mediate high antibody specificity. Next, we displayed this library on the surface of yeast, sorted it against Aβ42 aggregates, and identified promising clones using deep sequencing. The resulting antibodies displayed similar or higher affinities than clinical-stage Aβ antibodies (aducanumab and crenezumab). Moreover, the affinity-matured antibodies retained high conformational specificity for Aβ aggregates, as observed for aducanumab and unlike crenezumab. Notably, the affinity-maturated antibodies displayed extremely low levels of nonspecific interactions, as observed for crenezumab and unlike aducanumab. We expect that our systematic methods for generating antibodies with unique combinations of desirable properties will improve the generation of high-quality conformational antibodies specific for diverse types of aggregated conformers.

Purpose To investigate diffusion-time dependency of diffusional kurtosis in the mouse brain using pulsed-gradient spin-echo (PGSE) and oscillating-gradient spin-echo (OGSE) sequences. Methods 3D PGSE and OGSE kurtosis tensor data were acquired from ex vivo brains of adult, cuprizone-treated, and age-matched control mice with diffusion-time (tD ) ~ 20 ms and frequency (f) = 70 Hz, respectively. Further, 2D acquisitions were performed at multiple times/frequencies ranging from f = 140 Hz to tD = 30 ms with b-values up to 4000 s/mm2 . Monte Carlo simulations were used to investigate the coupled effects of varying restriction size and permeability on time/frequency-dependence of kurtosis with both diffusion-encoding schemes. Simulations and experiments were further performed to investigate the effect of varying number of cycles in OGSE waveforms. Results Kurtosis and diffusivity maps exhibited significant region-specific changes with diffusion time/frequency across both gray and white matter areas. PGSE- and OGSE-based kurtosis maps showed reversed contrast between gray matter regions in the cerebellar and cerebral cortex. Localized time/frequency-dependent changes in kurtosis tensor metrics were found in the splenium of the corpus callosum in cuprizone-treated mouse brains, corresponding to regional demyelination seen with histological assessment. Monte Carlo simulations showed that kurtosis estimates with pulsed- and oscillating-gradient waveforms differ in their sensitivity to exchange. Both simulations and experiments showed dependence of kurtosis on number of cycles in OGSE waveforms for non-zero permeability. Conclusion The results show significant time/frequency-dependency of diffusional kurtosis in the mouse brain, which can provide sensitivity to probe intrinsic cellular heterogeneity and pathological alterations in gray and white matter.

IntroductionThe identification of tumour mutational burden (TMB) as a biomarker of response to PD-1 immunotherapy has necessitated the development of genomic assays to measure this. We carried out comprehensive molecular profiling of cancers using the Illumina TruSight Oncology panel (TSO500) and compared to whole genome sequencing.MethodsCancer samples derived from formalin fixed material were profiled on the TSO500 panel, sequenced on an Illumina NextSeq 500 instrument and processed through the TSO500 Docker Pipeline. Either FASTQ files (PierianDx) or VCF files (OncoKDM) were processed to understand clinical actionabilityResultsIn total, 108 samples (a mixture of colorectal, lung, oesophageal and control samples) were processed via the DNA panel. There was good correlation between TMB, SNV, indels and CNV as predicted by TSO500 and WGS (R2>0.9) and good reproducibility, with less than 5% variability between repeated controls. For the RNA panel, 13 samples were processed, with all known fusions observed via orthogonal techniques detected. For clinical actionability 72 Tier 1 variants and 297 Tier 2 variants were identified with clinical trials identified for all patients.ConclusionsThe TruSight Oncology 500 assay accurately measures TMB, MSI, single nucleotide variants, indels, copy number/structural variation and gene fusions when compared to whole genome sequencing and orthogonal technologies. Coupled with a clinical annotation pipeline this provides a powerful methodology for identification of clinically actionable variants.

Multiple sclerosis (MS) is an inflammatory and demyelinating disease of the central nervous system (CNS) that results in variable severities of neurodegeneration. The understanding of MS has been limited by the inaccessibility of the affected cells and the lengthy timeframe of disease development. However, recent advances in stem cell technology have facilitated the bypassing of some of these challenges. Towards gaining a greater understanding of the innate potential of stem cells from people with varying degrees of disability, we generated induced pluripotent stem cells (iPSCs) from peripheral blood mononuclear cells derived from stable and progressive MS patients, and then further differentiated them into oligodendrocyte (OL) lineage cells. We analyzed differentiation under both homeostatic and inflammatory conditions via sustained exposure to low-dose interferon gamma (IFNγ), a prominent cytokine in MS. We found that all iPSC lines differentiated into mature myelinating OLs, but chronic exposure to IFNγ dramatically inhibited differentiation in both MS groups, particularly if exposure was initiated during the pre-progenitor stage. Low-dose IFNγ was not toxic but led to an early upregulation of interferon response genes in OPCs followed by an apparent redirection in lineage commitment from OL to a neuron-like phenotype in a significant portion of the treated cells. Our results reveal that a chronic low-grade inflammatory environment may have profound effects on the efficacy of regenerative therapies.

Objective Identify metabolic changes produced by dimethyl fumarate (DMF) treatment and link them to immunological effects. Methods We enrolled 18 MS patients and obtained blood prior to DMF and 6 months postinitiation. We also enrolled 18 healthy controls for comparison. We performed global metabolomics on plasma and used weighted correlation network analysis (WGCNA) to identify modules of correlated metabolites. We identified modules that changed with treatment, followed by targeted metabolomics to corroborate changes identified in global analyses. We correlated changes in metabolite modules and individual metabolites with changes in immunological parameters. Results We identified alterations in lipid metabolism after DMF treatment – increases in two modules (phospholipids, lysophospholipids and plasmalogens) and reduction in one module (saturated and poly‐unsaturated fatty acids) eigen‐metabolite values (all P

Dimethyl fumarate (DMF) treatment in multiple sclerosis (MS) increased the proportion of immunoregulatory CD56bright NK cells and this change was proportional to reductions in CD8+ memory T cells. DMF and monomethyl fumarate (MMF) treatment in vitro had directs effects on NK cells and promoted degranulation and cytotoxicity.

Summary The circulating metabolome provides unique insights into multiple sclerosis (MS) pathophysiology, but existing studies are relatively small or characterized limited metabolites. We test for differences in the metabolome between people with MS (PwMS; n = 637 samples) and healthy controls (HC; n = 317 samples) and assess the association between metabolomic profiles and disability in PwMS. We then assess whether metabolic differences correlate with changes in cellular gene expression using publicly available scRNA-seq data and whether identified metabolites affect human immune cell function. In PwMS, we identify striking abnormalities in aromatic amino acid (AAA) metabolites (p = 2.77E−18) that are also strongly associated with disability (p = 1.01E−4). Analysis of scRNA-seq data demonstrates altered AAA metabolism in CSF and blood-derived monocyte cell populations in PwMS. Treatment with AAA-derived metabolites in vitro alters monocytic endocytosis and pro-inflammatory cytokine production. We identify shifts in AAA metabolism resulting in the reduced production of immunomodulatory metabolites and increased production of metabotoxins in PwMS., Graphical abstract, Highlights • Significant alterations in the circulating metabolome are noted in multiple sclerosis • Aromatic amino acid (AAA) metabolite levels are linked to disease severity • Expression of AAA metabolism genes is altered in MS blood and CSF immune cells • AAA metabolites alter human monocyte cytokine production and endocytosis, Fitzgerald et al. identify alterations in circulating aromatic amino acid (AAA) metabolites in multiple sclerosis that are related to disease severity. They also demonstrate changes in AAA metabolism-related gene expression in blood and cerebrospinal fluid immune cells, and that treatment with AAA metabolites alters monocyte pro-inflammatory cytokine production and endocytosis.

Similar to organoammonium cations that template the well-studied layered perovskites, organosulfonium cations template the layered Pb–Br hybrid (tms)4Pb3Br10 (1; tms = (CH3)3S+). Upon ultraviolet excitation, this colorless, organic-inorganic hybrid exhibits broad red/near-infrared photoluminescence (PL) with a massive Stokes shift of ca. 1.7 eV. A suite of PL measurements suggests that the broad emission is an intrinsic property of the material. We ascribe this emission to radiative recombination of self-trapped excitons in the inorganic sublattice, which features both face- and corner-sharing Pb–Br octahedra. We further demonstrate that complex sulfonium-based cations can expand this family of lead-halide hybrids while maintaining the broad, Stokes-shifted PL. The use of more exotic main-group cations affords an exciting opportunity for synthetic chemists to expand the phase-space of semiconducting hybrids with unusual properties for potential applications in optoelectronics.

We evaluated the effect of dimethyl fumarate (DMF) treatment on B‐cell memory and cytokine production in 18 patients with relapsing remitting multiple sclerosis (RRMS) using peripheral blood mononuclear cells obtained prior to and at 6 months post‐DMF initiation. We noted a decline in the absolute B‐cell number with DMF treatment, with a preferential depletion of memory B cells and a concurrent increase in naïve B cells. We noted significant reductions in GM‐CSF, TNF‐α, and IL‐6 producing B cells with DMF treatment. These effects on the B‐cell compartment may underlie the beneficial effects of DMF in RRMS.

Glenn et al. show that EAE induction impairs influenza immune responses, worsens influenza pathology, and is marked by early EAE-induced recruitment of suppressive myeloid cells to the lungs., The discovery that central nervous system (CNS)–targeted autoreactive T cells required a process of licensing in the lung revealed an unexpected relationship between these organs. The clinical and immunological significance of this finding is bidirectional in that it showed not only a mechanism by which T cells become pathogenic before entering the CNS, but also the potential for this process to influence lung immunity as well. Epidemiological studies have shown that people with multiple sclerosis (MS) suffer from increased morbidity and mortality from infectious diseases, independent of immunosuppressive therapies. Respiratory infections account for a large percentage of deaths of people with MS. In this study, to investigate the mechanisms responsible for this enhanced susceptibility, we established a comorbid model system in which mice with experimental autoimmune encephalomyelitis (EAE) were administered a sublethal dose of influenza. Whereas mice with either EAE alone or influenza alone survived, 70% of comorbid mice died as a result of uncontrolled viral replication. Immunological analyses revealed that the induction of EAE led to a surprising alteration of the lung milieu, converting an effective stimulatory influenza-reactive environment into a suppressive one. These results provide mechanistic information that may help to explain the unexpected immunological interactions.

Background: Multiple myeloma (MM) remains an incurable plasma cell (PC) malignancy. Despite improvements in clinical outcomes, variability in treatment response exists. Some patients experience innate resistance, while others develop resistance over the course of treatment. Identifying signatures of treatment response and resistance is essential to predicting effective treatment strategies. Given the phenotypic clonal heterogeneity observed in MM, we hypothesize that resistant and sensitive subpopulations have unique phenotypic signatures. We used mass cytometry (CyTOF) to characterize primary MM samples and correlated their phenotypic signatures with treatment response. Methods: We characterized 102 primary MM samples by CyTOF using 37 antibodies (see figure). Frozen whole BM specimens were thawed, stained with antibodies, barcoded, and analyzed on a Helios mass cytometer. Data was processed using Cytobank or Pathsetter and analyzed using t-distributed stochastic neighbor embedding (t-SNE) algorithm. T-SNE plots for CD45+ cells were created using lineage defining markers. T-SNE plots of neoplastic PCs (CD138+,CD3-,CD16-,CD19-,cytoplasmic kappa or lambda+) were created using all remaining markers. A differential analysis of each sample's clusters was performed against all other events. Z-score values, representing marker changes from the differential analysis, for each cluster were used to group similar clusters across all samples, allowing us to compare sub populations of PCs between patients (see figure). From these groups of clusters with similar changes in markers, we calculated the proportion of cells with increases or decreases in markers for each sample. Results were compared to IMWG 90-day response criteria using a random forest model. Results: We performed mass cytometry on 102 samples from 68 unique MM patients. Median age was 66 years (range 34-95) with a 1.5:1 male:female ratio. 37 (36%) had NDMM, 55 (54%) had RRMM, 2 (2%) had SMM and 8 cases (8%) had unknown status. FISH studies revealed 47 (46%) had hyperdiploidy without a recurrent primary IgH rearrangement, 31 (30%) had t(11;14), 13 (13%) had t(4;14), 5 (5%) had 14;16 or 14;20, 3 (3%) had hyperhaploidy and 3 (3%) had an undefined primary. 54 (53%) had 1q gain/amp, 22 (22%) had TP53 deletion, 22 (22%) had a MYC rearrangement and 71% had high mSMART risk. Nearly all patients received an immunomodulatory compound, a proteasome inhibitor and dexamethasone. 2 (2%) had complete response (CR), 10 (9.8%) very good partial response (VGPR), 36 (35%) had partial response (PR), 14 (14%) had minimal response (MR), 13 (13%) had stable disease (SD) and 17 (17%) had progressive disease (PD). Characterization of CD45+ cells identified a relatively conserved and reproducible map from each patient. Notable differences included an ~2-fold reduction in the percentage of total B cells (CD45+,CD3-,CD19+)/total CD45+ cells in cases with high risk mSMART, RRMM and TP53 deletion compared to cases with standard risk, NDMM or normal TP53 status. Similar B-cell reductions were found in RRMM vs. NDMM samples from matched-patients. In contrast to the conserved t-SNE structure of the CD45+ population, the neoplastic PC population displayed dramatically reduced t-SNE structural consistency. Heterogeneity between patient samples and between the same patient samples over time was observed. We focused our analysis on 22 patients with serial samples. The proportion of each t-SNE group present in each patient sample was calculated and then correlated to the 90-day response metric. We identified a phenotypic group whose proportion increased in relation to disease progression (R2=0.85). This group had elevated BCL-2, pSTAT3, CD56 levels and reduced CD45 and CD81 levels. Evaluating individual markers, we found an increase in the proportion of cells with elevated BCL-2, pS6, Ki67, and IKZF1 levels in relation to disease progression. We also observed an increase in the proportion of cells with reduced pCREB levels and a reduction in the proportion of cells with reduced CD147 levels in relation to disease progression. Conclusions: We have utilized CyTOF to characterize phenotypic and functional markers in MM cells on a single cell level and can identify unique subgroups that change in relation to disease progression. Future analysis will correlate phenotypic signatures with ISS stage, mSMART risk, cytogenetic abnormality and type of treatment. Figure 1 Disclosures Kumar: Kite Pharma: Consultancy, Research Funding; Oncopeptides: Consultancy, Other: Independent Review Committee; IRC member; Celgene/BMS: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Takeda: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Sanofi: Research Funding; MedImmune: Research Funding; Karyopharm: Consultancy; Merck: Consultancy, Research Funding; Carsgen: Other, Research Funding; Cellectar: Other; Novartis: Research Funding; Adaptive Biotechnologies: Consultancy; AbbVie: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Genecentrix: Consultancy; Genentech/Roche: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Janssen Oncology: Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments; Amgen: Consultancy, Other: Research funding for clinical trials to the institution, Consulting/Advisory Board participation with no personal payments, Research Funding; Tenebio: Other, Research Funding; BMS: Consultancy, Research Funding; Dr. Reddy's Laboratories: Honoraria.

For reasons that are not completely understood, remyelination is often incomplete, producing thin myelin sheaths with disorganized structure. We investigated the cellular basis for this altered myelin structure, and found that the response of oligodendrocyte progenitor cells (OPCs), and mature oligodendrocytes to TNFα and IL-1β is modified by the expression of the sphingomyelin hydrolase nSMase2. OPCs do not express nSMase2, and exhibit a protective response to these cytokines manifest by decreased ceramide, increased sphingosine 1-phosphate, and increased cell motility. Mature oligodendrocytes express nSMase2, and respond to TNFα and IL-1β with a stress phenotype, evidenced by increased ceramide, decreased sphingosine, and active caspase 3. Pharmacological inhibition or a targeted genetic deletion of nSMase2in vivoincreased myelin thickness, and enhanced myelin compaction. These results suggest that inhibition of nSMase2 improves the quality of new myelin by protecting maturing/myelinating oligodendrocytes. Pharmacological inhibition of nSMase2 following a demyelinating event could stabilize the structure of these newly formed myelin sheaths and protect them from secondary demyelination.

The animal model experimental autoimmune encephalomyelitis (EAE) has been used extensively in the past to test mechanisms that target peripheral immune cells for treatment of multiple sclerosis (MS). While there have been some notable successes in relapsing MS, the development of therapies for progressive multiple sclerosis (MS) has been hampered by lack of an appropriate animal model. Further, the mechanisms underlying CNS inflammation and neuronal injury remain incompletely elucidated. It is known that the MOG 35–55 EAE mouse model does not have insidious behavioral progression as occurs in people with MS, but there is significant neuronal and axonal injury in EAE, as a result of the inflammation. In the present study, we describe the time course of glial activation and retinal neurodegeneration in the EAE model, and highlight the utility of studying the anterior visual pathway for modeling mechanisms of neuronal injury that may recapitulate critical aspects of the pathology described in people with MS following optic neuritis and subclinical optic neuropathy. We show that A1 neurotoxic astrocytes are prevalent in optic nerve tissue and retina, and are associated with subsequent RGC loss in the most commonly used form of the EAE model induced by MOG 35–55 peptide in C57/B6 mice. We developed a semi-automatic method to quantify retinal ganglion cells (RGC) and show that RGCs remain intact at peak EAE (PID 16) but are significantly reduced in late EAE (PID 42). Postsynaptic proteins and neurites were also compromised in the retina of late EAE mice. The retinal pathology manifests weeks after the microglial and astrocyte activation, which were prominent in optic nerve tissues at PID 16. Microglia expressed iNOS and had increased gene expression of C1q, TNF-α, and IL-1α. Astrocytes expressed high levels of complement component 3 and other genes associated with A1 neurotoxic astrocytes. Our data suggest that EAE can be used to study the pathobiology of optic neuropathy and to examine the preclinical neuroprotective effects of drugs that target activation of neurotoxic A1 astrocytes. Electronic supplementary material The online version of this article (10.1186/s40478-019-0767-6) contains supplementary material, which is available to authorized users.

Multiple sclerosis (MS) is an inflammatory demyelinating disorder of the CNS. Bile acids are cholesterol metabolites that can signal through receptors on cells throughout the body, including in the CNS and the immune system. Whether bile acid metabolism is abnormal in MS is unknown. Using global and targeted metabolomic profiling, we identified lower levels of circulating bile acid metabolites in multiple cohorts of adult and pediatric patients with MS compared with controls. In white matter lesions from MS brain tissue, we noted the presence of bile acid receptors on immune and glial cells. To mechanistically examine the implications of lower levels of bile acids in MS, we studied the in vitro effects of an endogenous bile acid, tauroursodeoxycholic acid (TUDCA), on astrocyte and microglial polarization. TUDCA prevented neurotoxic (A1) polarization of astrocytes and proinflammatory polarization of microglia in a dose-dependent manner. TUDCA supplementation in experimental autoimmune encephalomyelitis reduced the severity of disease through its effects on G protein-coupled bile acid receptor 1 (GPBAR1). We demonstrate that bile acid metabolism was altered in MS and that bile acid supplementation prevented polarization of astrocytes and microglia to neurotoxic phenotypes and ameliorated neuropathology in an animal model of MS. These findings identify dysregulated bile acid metabolism as a potential therapeutic target in MS.

Multiple sclerosis (MS) is an inflammatory demyelinating disorder of the CNS. Bile acids are cholesterol metabolites that can signal through receptors on cells throughout the body, including the CNS and immune system. Whether bile acid metabolism is abnormal in MS is unknown. Using global and targeted metabolomic profiling, we identified lower levels of circulating bile acid metabolites in multiple cohorts of adult and pediatric MS patients compared to controls. In white matter lesions from MS brain tissue, we noted the presence of bile acid receptors on immune and glial cells. To mechanistically examine the implications of lower levels of bile acids in MS, we studied the in vitro effects of an endogenous bile acid – tauroursodeoxycholic acid (TUDCA) on astrocyte and microglial polarization. TUDCA prevented neurotoxic (A1) polarization of astrocytes and pro-inflammatory polarization of microglia in a dose-dependent manner. TUDCA supplementation in experimental autoimmune encephalomyelitis reduced severity of disease, based on behavioral and pathological measures. We demonstrate that bile acid metabolism is altered in MS; bile acid supplementation prevents polarization of astrocytes and microglia to neurotoxic phenotypes and ameliorates neuropathology in an animal model of MS. These findings identify dysregulated bile acid metabolism as a potential therapeutic target in MS.

Layered halide perovskites offer a versatile platform for manipulating light through synthetic design. Although most layered perovskites absorb strongly in the ultraviolet (UV) or near-UV region, their emission can range from the UV to the infrared region of the electromagnetic spectrum. This emission can be very narrow, displaying high color purity, or it can be extremely broad, spanning the entire visible spectrum and providing high color rendition (or accurately reproducing illuminated colors). The origin of the photoluminescence can vary enormously. Strongly correlated electron-hole pairs, permanent lattice defects, transient light-induced defects, and ligand-field transitions in the inorganic layers and molecular chromophores in the organic layers can be involved in the emission mechanism. In this review, we highlight the different types of photoluminescence that may be attained from layered halide perovskites, with an emphasis on how the emission may be systematically tuned through changes to the bulk crystalline lattice: changes in composition, structure, and dimensionality.

Multiple sclerosis (MS) is characterized by demyelinated lesions in the central nervous system. Destruction of myelin and secondary damage to axons and neurons leads to significant disability, particularly in people with progressive MS. Accumulating evidence suggests that the potential for myelin repair exists in MS, although for unclear reasons this process fails. The cells responsible for producing myelin, the oligodendrocytes, and their progenitors, oligodendrocyte precursor cells (OPCs), have been identified at the site of lesions, even in adults. Their presence suggests the possibility that endogenous remyelination without transplantation of donor stem cells may be a mechanism for myelin repair in MS. Strategies to develop novel therapies have focused on induction of signaling pathways that stimulate OPCs to mature into myelin-producing oligodendrocytes that could then possibly remyelinate lesions. We have been investigating pharmacological approaches to enhance OPC differentiation, and have identified that the combination of two agents, triiodothyronine (T3) and quetiapine, leads to an additive effect on OPC differentiation and consequent myelin production via both overlapping and distinct signaling pathways. While the ultimate production of myelin requires cholesterol biosynthesis, we identified that quetiapine enhances gene expression in this pathway more potently than T3. Two blockers of cholesterol production, betulin and simvastatin, reduced OPC differentiation into myelin producing oligodendrocytes. Elucidating the nature of agents that lead to complementary and additive effects on oligodendrocyte differentiation and myelin production may pave the way for more efficient induction of remyelination in people with MS.

INTRODUCTION: We report a novel attempt to relieve venous cannula outflow obstruction utilizing temporary dialysis catheters connected to a continuous renal replacement therapy (CRRT) circuit to provide alternative venous return METHODS: A 57-year-old male with a history of type 2 diabetes was diagnosed with SARS-COV-2 at an outside hospital He required intubation and mechanical ventilation He continued to have declining respiratory function and was transferred for veno-venous ECMO support The inflow cannula was placed in the left femoral vein and the outflow cannula in the right femoral vein On ECMO day 2 the patient was noted to have edema of the left lower extremity (LLE) concerning for thrombosis and/or venous outflow obstruction from the ECMO cannula This continued to worsen, and by ECLS day 5 the patient's LLE began to show signs of phlegmasia cerulea dolens As such, we were forced with the decision to either attempt to relieve the obstruction or decannulate the patient The vascular surgery team was consulted to assist In our institution, we prefer to extubate or perform tracheostomy while still on ECMO Therefore, we attempted to relieve the obstruction first The vascular surgeons elected to place two temporary dialysis catheters: one in the left lesser saphenous vein and one in the right internal jugular vein The catheters were then connected using a CRRT circuit The goal was to provide additional venous drainage for the LLE using the CRRT circuit to pump and filter before returning the blood to the right atrium Unfortunately, we were not able to generate the blood flows necessary for the CRRT circuit to function We then attempted to make a direct connection between the two catheters with standard intravenous tubing hoping that the pressure in the venous system in the LLE would be high enough to let blood flow through the tubing without the assistance of a pump This worked initially, but the IV tubing eventually clotted Ultimately, the decision was made to decannulate the patient and transition to more aggressive ventilator strategies RESULTS: We may attempt this again in the future to relieve outflow obstruction However, only if it is possible to use a larger vein for the outflow catheter to generate the requisite flows