Prevalence of anti-myelin oligodendrocyte glycoprotein antibodies across neuroinflammatory and neurodegenerative diseases

Inflammatory central nervous system (CNS) diseases, such as multiple sclerosis (MS) and myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD), are characterized by humoral immune abnormalities. Anti-MOG antibodies are not specific to MOGAD, with their presence described in MS. Autoantibodies may also be present and play a role in various neurodegenerative diseases. Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease driven by motor neuron dysfunction. While immune involvement in ALS has been recognized, the presence of antibodies targeting CNS myelin antigens has not been established. We aimed to establish a live cell-based assay for quantification of serum anti-MOG IgG1 in patients with CNS diseases, including MS and ALS. In total, 771 serum samples from the John L. Trotter MS Center and the Northeast ALS Consortium were examined using a live cell-based assay for detection of anti-MOG IgG1. Samples from three cohorts were tested in blinded fashion: healthy control (HC) subjects, patients with clinically diagnosed MOGAD, and an experimental group of ALS and MS patients. All samples from established MOGAD cases were positive for anti-MOG antibodies, while all HC samples were negative. Anti-MOG IgG1 was detected in 65 of 658 samples (9.9%) from MS subjects and 4 of 108 (3.7%) samples from ALS subjects. The presence of serum anti-MOG IgG1 in MS and ALS patients raises questions about the contribution of these antibodies to disease pathophysiology as well as accuracy of diagnostic approaches for CNS inflammatory diseases.

Sex differences in plasma proteomic markers in late-life depression

Previous studies have shown significant sex-specific differences in major depressive disorder (MDD) in multiple biological parameters. Most studies focused on young and middle-aged adults, and there is a paucity of information about sex-specific biological differences in older adults with depression (aka, late-life depression (LLD)). To address this gap, this study aimed to evaluate sex-specific biological abnormalities in a large group of individuals with LLD using an untargeted proteomic analysis. We quantified 344 plasma proteins using a multiplex assay in 430 individuals with LLD and 140 healthy comparisons (HC) (age range between 60 and 85 years old for both groups). Sixty-six signaling proteins were differentially expressed in LLD (both sexes). Thirty-three proteins were uniquely associated with LLD in females, while six proteins were uniquely associated with LLD in males. The main biological processes affected by these proteins in females were related to immunoinflammatory control. In contrast, despite the smaller number of associated proteins, males showed dysregulations in a broader range of biological pathways, including immune regulation pathways, cell cycle control, and metabolic control. Sex has a significant impact on biomarker changes in LLD. Despite some overlap in differentially expressed biomarkers, males and females show different patterns of biomarkers changes, and males with LLD exhibit abnormalities in a larger set of biological processes compared to females. Our findings can provide novel targets for sex-specific interventions in LLD.

Transient Receptor Potential Vanilloid 4-Dependent Microglial Function in Myelin Injury and Repair

Microglia are found pathologically at all stages of multiple sclerosis (MS) lesion development and are hypothesized to contribute to both inflammatory injury and neuroprotection in the MS brain. Transient receptor potential vanilloid 4 (TRPV4) channels are widely expressed, play an important role as environmental sensors, and are involved in calcium homeostasis for a variety of cells. TRPV4 modulates myeloid cell phagocytosis in the periphery and microglial motility in the central nervous system. We hypothesized that TRPV4 deletion would alter microglia phagocytosis in vitro and lessen disease activity and demyelination in experimental autoimmune encephalitis (EAE) and cuprizone-induced demyelination. We found that genetic deletion of TRPV4 led to increased microglial phagocytosis in vitro but did not alter the degree of demyelination or remyelination in the cuprizone mouse model of MS. We also found no difference in disease in EAE following global or microglia-specific deletion of Trpv4. Additionally, lesioned and normal appearing white matter from MS brains exhibited similar TRPV4 expression compared to healthy brain tissue. Taken together, these findings indicate that TRPV4 modulates microglial activity but does not impact disease activity in mouse models of MS, suggesting a muted and/or redundant role in MS pathogenesis.

Quantitative Analysis of S1PR1 Expression in the Postmortem Multiple Sclerosis Central Nervous System

Multiple sclerosis (MS) is an immune-mediated disease that is characterized by demyelination and inflammation in the central nervous system (CNS). Previous studies demonstrated that sphingosine-1-phosphate receptor (S1PR) modulators effectively inhibit S1PR1 in immune cell trafficking and reduce entry of pathogenic cells into the CNS. Studies have also implicated a nonimmune, inflammatory role of S1PR1 within the CNS in MS. In this study, we explored the expression of S1PR1 in the development and progression of demyelinating pathology of MS by quantitative assessment of S1PR1 expression using our S1PR1-specific radioligand, [3H]CS1P1, in the postmortem human CNS tissues including cortex, cerebellum, and spinal cord of MS cases and age- and sex-matched healthy cases. Immunohistochemistry with whole slide scanning for S1PR1 and various myelin proteins was also performed. Autoradiographic analysis using [3H]CS1P1 showed that the expression of S1PR1 was statistically significantly elevated in lesions compared to nonlesion regions in the MS cases, as well as normal healthy controls. The uptake of [3H]CS1P1 in the gray matter and nonlesion white matter did not significantly differ between healthy and MS CNS tissues. Saturation autoradiography analysis showed an increased binding affinity (Kd) of [3H]CS1P1 to S1PR1 in both gray matter and white matter of MS brains compared to healthy brains. Our blocking study using NIBR-0213, a S1PR1 antagonist, indicated [3H]CS1P1 is highly specific to S1PR1. Our findings demonstrated the activation of S1PR1 and an increased uptake of [3H]CS1P1 in the lesions of MS CNS. In summary, our quantitative autoradiography analysis using [3H]CS1P1 on human postmortem tissues shows the feasibility of novel imaging strategies for MS by targeting S1PR1.

Demographics and baseline disease characteristics of Black and Hispanic patients with multiple sclerosis in the open-label, single-arm, multicenter, phase IV CHIMES trial

BACKGROUND

Black/African American patients with multiple sclerosis (BpwMS) and Hispanic/Latino patients with multiple sclerosis (HpwMS), who historically have been underrepresented in multiple sclerosis (MS) clinical trials, exhibit greater disease severity and more rapid disease progression than White patients with MS (WpwMS). The lack of diversity and inclusion in clinical trials, which may be due to barriers at the system, patient and study levels, impacts the ability to effectively assess risks, benefits and treatment responses in a generalized patient population.

METHODS

CHIMES (Characterization of Ocrelizumab in Minorities With Multiple Sclerosis), an open-label, single-arm, multicenter, phase IV study of self-identified BpwMS and HpwMS aged 18-65 years with relapsing MS and an Expanded Disability Status Score (EDSS) of ≤5.5, was developed in collaboration with patients with MS, national advocacy groups and clinical researchers. Patients were enrolled at study centers across the US, including Puerto Rico, and 1 site in Kenya.

RESULTS

A total of 182 patients enrolled in CHIMES: 113 (62.1%) were BpwMS, and 69 (37.9%) were HpwMS; the mean (SD) baseline EDSS score was 2.4 (1.4), and 62.6% of patients were treatment naive. Using the pooled non-BpwMS/HpwMS group in the OPERA ocrelizumab trials as a reference population, patients enrolled in CHIMES were younger, had a higher mean body mass and had a greater T2 lesion volume but similar T2 lesion number on MRI.

CONCLUSION

BpwMS and HpwMS have been consistently underrepresented in clinical trials, limiting the understanding of disease biology and response to treatment in this population. Data from the CHIMES study revealed differences in demographics and some baseline disease characteristics and disease burden between BpwMS and HpwMS vs WpwMS. These differences could have an impact when assessing clinical outcomes in BpwMS and HpwMS.

CLINICALTRIALS

GOV IDENTIFIER

NCT04377555.

Quantitative MRI identifies lesional and non-lesional abnormalities in MOGAD

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a distinct central nervous system (CNS) disorder that shares features with multiple sclerosis (MS) and may be misdiagnosed as MS. MOGAD and MS share a frequently relapsing clinical course and lesions with inflammatory demyelinating pathology. One key feature of MS pathology is tissue damage in normal-appearing white matter (NAWM) outside of discrete lesions, whereas the extent to which similar non-lesional damage occurs in MOGAD is not known and could be assessed using qGRE. The goal of this study was to examine the brains of people with MOGAD using quantitative gradient-recalled echo (qGRE) magnetic resonance imaging and to compare tissue damage with MS patients matched for disability.

METHODS

MOGAD and MS patients were recruited to match in terms of age and disability. Similarly aged healthy control (HC) data were drawn from existing studies. qGRE brain imaging of HC (N = 15), MOGAD (N = 17), and MS (N = 15) patients was used to examine the severity and extent of tissue damage within and outside of discrete lesions. The qGRE metric R2t* is sensitive to changes in tissue microstructure and was measured in white matter lesions (WMLs), NAWM, cortical (CGM) and deep gray matter (DGM). Statistical inference was performed with linear models.

RESULTS

R2t* was reduced in CGM (p = 0.00047), DGM (p = 0.0055) and NAWM (p = 0.0019) in MOGAD and MS compared to similar regions in age-matched HCs. However, the degree of R2t* reduction in all these regions was less in the MOGAD patients compared with MS. WMLs in MOGAD demonstrated reduced R2t* compared to NAWM but this reduction was modest compared to changes associated with WMLs in MS (p = 0.026).

CONCLUSION

These results demonstrate abnormalities in lesional and non-lesional CNS tissues in MOGAD that are not detectable on standard MRI. The abnormalities seen in NAWM, CGM, and DGM were less severe in MOGAD compared to MS. MOGAD-related WMLs showed reduced R2t*, but were less abnormal than WMLs in MS. These data reveal damage to non-lesional tissues in two different demyelinating diseases, suggesting that damage outside of WMLs may be a common feature of demyelinating diseases. The lesser degree of R2t* abnormality in MOGAD tissues compared to MS suggests less underlying tissue damage and may underlie the greater propensity for recovery in MOGAD.

MrgprA3-expressing pruriceptors drive pruritogen-induced alloknesis through mechanosensitive Piezo2 channel

Although touch and itch are coded by distinct neuronal populations, light touch also provokes itch in the presence of exogenous pruritogens, resulting in a phenomenon called alloknesis. However, the cellular and molecular mechanisms underlying the initiation of pruritogen-induced mechanical itch sensitization are poorly understood. Here, we show that intradermal injections of histamine or chloroquine (CQ) provoke alloknesis through activation of TRPV1- and MrgprA3-expressing prurioceptors, and functional ablation of these neurons reverses pruritogen-induced alloknesis. Moreover, genetic ablation of mechanosensitive Piezo2 channel function from MrgprA3-expressing prurioceptors also dampens pruritogen-induced alloknesis. Mechanistically, histamine and CQ sensitize Piezo2 channel function, at least in part, through activation of the phospholipase C (PLC) and protein kinase C-δ (PKCδ) signaling. Collectively, our data find a TRPV1+/MrgprA3+ prurioceptor-Piezo2 signaling axis in the initiation of pruritogen-induced mechanical itch sensitization in the skin.

CAR-T Cell-Mediated B-Cell Depletion in Central Nervous System Autoimmunity

BACKGROUND AND OBJECTIVES

Anti-CD20 monoclonal antibody (mAb) B-cell depletion is a remarkably successful multiple sclerosis (MS) treatment. Chimeric antigen receptor (CAR)-T cells, which target antigens in a non-major histocompatibility complex (MHC)-restricted manner, can penetrate tissues more thoroughly than mAbs. However, a previous study indicated that anti-CD19 CAR-T cells can paradoxically exacerbate experimental autoimmune encephalomyelitis (EAE) disease. We tested anti-CD19 CAR-T cells in a B-cell-dependent EAE model that is responsive to anti-CD20 B-cell depletion similar to the clinical benefit of anti-CD20 mAb treatment in MS.

METHODS

Anti-CD19 CAR-T cells or control cells that overexpressed green fluorescent protein were transferred into C57BL/6 mice pretreated with cyclophosphamide (Cy). Mice were immunized with recombinant human (rh) myelin oligodendrocyte protein (MOG), which causes EAE in a B-cell-dependent manner. Mice were evaluated for B-cell depletion, clinical and histologic signs of EAE, and immune modulation.

RESULTS

Clinical scores and lymphocyte infiltration were reduced in mice treated with either anti-CD19 CAR-T cells with Cy or control cells with Cy, but not with Cy alone. B-cell depletion was observed in peripheral lymphoid tissue and in the CNS of mice treated with anti-CD19 CAR-T cells with Cy pretreatment. Th1 or Th17 populations did not differ in anti-CD19 CAR-T cell, control cell-treated animals, or Cy alone.

DISCUSSION

In contrast to previous data showing that anti-CD19 CAR-T cell treatment exacerbated EAE, we observed that anti-CD19 CAR-T cells ameliorated EAE. In addition, anti-CD19 CAR-T cells thoroughly depleted B cells in peripheral tissues and in the CNS. However, the clinical benefit occurred independently of antigen specificity or B-cell depletion.

A TRPV4-dependent neuroimmune axis in the spinal cord promotes neuropathic pain

Microglia, resident macrophages of the CNS, are essential to brain development, homeostasis, and disease. Microglial activation and proliferation are hallmarks of many CNS diseases, including neuropathic pain. However, molecular mechanisms that govern the spinal neuroimmune axis in the setting of neuropathic pain remain incompletely understood. Here, we show that genetic ablation or pharmacological blockade of transient receptor potential vanilloid type 4 (TRPV4) markedly attenuated neuropathic pain-like behaviors in a mouse model of spared nerve injury. Mechanistically, microglia-expressed TRPV4 mediated microglial activation and proliferation and promoted functional and structural plasticity of excitatory spinal neurons through release of lipocalin-2. Our results suggest that microglial TRPV4 channels reside at the center of the neuroimmune axis in the spinal cord, which transforms peripheral nerve injury into central sensitization and neuropathic pain, thereby identifying TRPV4 as a potential new target for the treatment of chronic pain.

The cerebrospinal fluid immune cell landscape in animal models of multiple sclerosis

The fluid compartment surrounding the central nervous system (CNS) is a unique source of immune cells capable of reflecting the pathophysiology of neurologic diseases. While human clinical and experimental studies often employ cerebrospinal fluid (CSF) analysis, assessment of CSF in animal models of disease are wholly uncommon, particularly in examining the cellular component. Barriers to routine assessment of CSF in animal models of multiple sclerosis (MS) include limited sample volume, blood contamination, and lack of feasible longitudinal approaches. The few studies characterizing CSF immune cells in animal models of MS are largely outdated, but recent work employing transcriptomics have been used to explore new concepts in CNS inflammation and MS. Absence of extensive CSF data from rodent and other systems has curbed the overall impact of experimental models of MS. Future approaches, including examination of CSF myeloid subsets, single cell transcriptomics incorporating antigen receptor sequencing, and use of diverse animal models, may serve to overcome current limitations and provide critical insights into the pathogenesis of, and therapeutic developments for, MS.

Late-Life Depression is Associated With Increased Levels of GDF-15, a Pro-Aging Mitokine

OBJECTIVE

In older adults, major depressive disorder (MDD) is associated with accelerated physiological and cognitive aging, generating interest in uncovering biological pathways that may be targetable by interventions. Growth differentiation factor-15 (GDF-15) plays a significant role in biological aging via multiple biological pathways relevant to age and age-related diseases. Elevated levels of GDF-15 correlate with increasing chronological age, decreased telomerase activity, and increased mortality risk in older adults. We sought to evaluate the circulating levels of GDF-15 in older adults with MDD and its association with depression severity, physical comorbidity burden, age of onset of first depressive episode, and cognitive performance.

DESIGN

This study assayed circulating levels of GDF-15 in 393 older adults (mean ± SD age 70 ± 6.6 years, male:female ratio 1:1.54), 308 with MDD and 85 non-depressed comparison individuals.

RESULTS

After adjusting for confounding variables, depressed older adults had significantly higher GDF-15 serum levels (640.1 ± 501.5 ng/mL) than comparison individuals (431.90 ± 223.35 ng/mL) (t=3.75, d.f.= 391, p=0.0002). Among depressed individuals, those with high GDF-15 had higher levels of comorbid physical illness, lower executive cognitive functioning, and higher likelihood of having late-onset depression.

CONCLUSION

Our results suggest that depression in late life is associated with GDF-15, a marker of amplified age-related biological changes. GDF-15 is a novel and potentially targetable biological pathway between depression and accelerated aging, including cognitive aging.

Effects of Mindfulness Training and Exercise on Cognitive Function in Older Adults: A Randomized Clinical Trial

IMPORTANCE

Episodic memory and executive function are essential aspects of cognitive functioning that decline with aging. This decline may be ameliorable with lifestyle interventions.

OBJECTIVE

To determine whether mindfulness-based stress reduction (MBSR), exercise, or a combination of both improve cognitive function in older adults.

DESIGN, SETTING, AND PARTICIPANTS

This 2 × 2 factorial randomized clinical trial was conducted at 2 US sites (Washington University in St Louis and University of California, San Diego). A total of 585 older adults (aged 65-84 y) with subjective cognitive concerns, but not dementia, were randomized (enrollment from November 19, 2015, to January 23, 2019; final follow-up on March 16, 2020).

INTERVENTIONS

Participants were randomized to undergo the following interventions: MBSR with a target of 60 minutes daily of meditation (n = 150); exercise with aerobic, strength, and functional components with a target of at least 300 minutes weekly (n = 138); combined MBSR and exercise (n = 144); or a health education control group (n = 153). Interventions lasted 18 months and consisted of group-based classes and home practice.

MAIN OUTCOMES AND MEASURES

The 2 primary outcomes were composites of episodic memory and executive function (standardized to a mean [SD] of 0 [1]; higher composite scores indicate better cognitive performance) from neuropsychological testing; the primary end point was 6 months and the secondary end point was 18 months. There were 5 reported secondary outcomes: hippocampal volume and dorsolateral prefrontal cortex thickness and surface area from structural magnetic resonance imaging and functional cognitive capacity and self-reported cognitive concerns.

RESULTS

Among 585 randomized participants (mean age, 71.5 years; 424 [72.5%] women), 568 (97.1%) completed 6 months in the trial and 475 (81.2%) completed 18 months. At 6 months, there was no significant effect of mindfulness training or exercise on episodic memory (MBSR vs no MBSR: 0.44 vs 0.48; mean difference, -0.04 points [95% CI, -0.15 to 0.07]; P = .50; exercise vs no exercise: 0.49 vs 0.42; difference, 0.07 [95% CI, -0.04 to 0.17]; P = .23) or executive function (MBSR vs no MBSR: 0.39 vs 0.31; mean difference, 0.08 points [95% CI, -0.02 to 0.19]; P = .12; exercise vs no exercise: 0.39 vs 0.32; difference, 0.07 [95% CI, -0.03 to 0.18]; P = .17) and there were no intervention effects at the secondary end point of 18 months. There was no significant interaction between mindfulness training and exercise (P = .93 for memory and P = .29 for executive function) at 6 months. Of the 5 prespecified secondary outcomes, none showed a significant improvement with either intervention compared with those not receiving the intervention.

CONCLUSIONS AND RELEVANCE

Among older adults with subjective cognitive concerns, mindfulness training, exercise, or both did not result in significant differences in improvement in episodic memory or executive function at 6 months. The findings do not support the use of these interventions for improving cognition in older adults with subjective cognitive concerns.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02665481.

A single-cell analysis framework allows for characterization of CSF leukocytes and their tissue of origin in multiple sclerosis

Peripheral central nervous system (CNS)-infiltrating lymphocytes are a hallmark of relapsing-remitting multiple sclerosis. Tissue-resident memory T cells (T_RM) not only populate the healthy CNS parenchyma but also are suspected to contribute to multiple sclerosis pathology. Because cerebrospinal fluid (CSF), unlike CNS parenchyma, is accessible for diagnostics, we evaluated whether human CSF, apart from infiltrating cells, also contains T_RM cells and CNS-resident myeloid cells draining from the parenchyma or border tissues. Using deep generative models, we integrated 41 CSF and 14 CNS parenchyma single-cell RNA sequencing (scRNAseq) samples from eight independent studies, encompassing 120,629 cells. By comparing CSF immune cells collected during multiple sclerosis relapse with cells collected during therapeutic very late antigen-4 blockade, we could identify immune subsets with tissue provenance across multiple lineages, including CNS border-associated macrophages, CD8 and CD4 T_RM cells, and tissue-resident natural killer cells. All lymphocytic CNS-resident cells shared expression of CXCR6 but showed differential ITGAE expression (encoding CD103). A common signature defined CD4 and CD8 T_RM cells by expression of ZFP36L2, DUSP1, and ID2. We further developed a user interface-driven application based on this analysis framework for atlas-level cell identity transfer onto new CSF scRNAseq data. Together, these results define CNS-resident immune cells involved in multiple sclerosis pathology that can be detected and monitored in CSF. Targeting these cell populations might be promising to modulate immunopathology in progressive multiple sclerosis and other neuroinflammatory diseases.

Assessment of Pretreatment and Posttreatment Evolution of Neurofilament Light Chain Levels in Patients Who Develop Immune Effector Cell-Associated Neurotoxicity Syndrome

Importance

Determining whether neurofilament light chain (NfL) elevations in patients who develop immune effector cell-associated neurotoxicity syndrome (ICANS) occur before or after infusion of cellular product is important to identify high-risk patients and inform whether neuroaxonal injury is latent or a consequence of treatment.

Objective

To quantify serial NfL levels in patients undergoing cellular therapy.

Design, Setting, and Participants

This retrospective 2-center study examined plasma NfL levels in 30 patients with detailed medical and treatment history, including all major pretreatment and posttreatment risk factors. Exclusion criteria included dementia and severe, symptomatic central nervous system (CNS) involvement.

Main Outcomes and Measures

Patients' NfL levels were measured at 7 time points: baseline (prelymphodepletion), during lymphodepletion, postinfusion day (D) 1, D3, D7, D14, and D30. Prediction accuracy for the development of ICANS was next modeled using receiver operating characteristic (ROC) classification. Finally, univariate and multivariate modeling examined the association between NfL levels, ICANS, and potential risk factors including demographic (age, sex), oncologic (tumor burden, history of CNS involvement), neurologic (history of nononcologic CNS disease or neuropathy), and neurotoxic exposure histories (vincristine, cytarabine, methotrexate, or CNS radiotherapy).

Results

A total of 30 patients (median [range] age, 64 [22-80] years; 12 women [40%] and 18 men [60%]) were included. Individuals who developed ICANS had elevations in NfL prior to lymphodepletion and chimeric antigen receptor T-cell infusion compared with those who did not develop ICANS (no ICANS: 29.4 pg/mL, vs any ICANS: 87.6 pg/mL; P < .001). Baseline NfL levels further predicted ICANS development with high accuracy (area under the ROC curve, 0.96), sensitivity (0.91), and specificity (0.95). Levels of NfL remained elevated across all time points, up to 30 days postinfusion. Baseline NfL levels correlated with ICANS severity but not demographic factors, oncologic history, nononcologic neurologic history, or history of exposure to neurotoxic therapies.

Conclusions and Relevance

In a subset of patients in this cross-sectional study, the risk of developing ICANS was associated with preexisting neuroaxonal injury that was quantifiable with plasma NfL level. This latent neuroaxonal injury was present prior to drug administration but was not associated with historic neurotoxic therapies or nononcologic neurologic disease. Preinfusion NfL may further permit early screening and identification of patients most at risk for ICANS. Additional studies are needed to determine NfL's utility as a predictive biomarker for early (preemptive or prophylactic) intervention and to delineate the origin of this underlying neural injury.

Antigen-specific depletion of CD4+ T cells by CAR T cells reveals distinct roles of higher- and lower-affinity TCRs during autoimmunity

Both higher- and lower-affinity self-reactive CD4⁺ T cells are expanded in autoimmunity; however, their individual contribution to disease remains unclear. We addressed this question using peptide-MHCII chimeric antigen receptor (pMHCII-CAR) T cells to specifically deplete peptide-reactive T cells in mice. Integration of improvements in CAR engineering with TCR repertoire analysis was critical for interrogating in vivo the role of TCR affinity in autoimmunity. Our original MOG_35-55 pMHCII-CAR, which targeted only higher-affinity TCRs, could prevent the induction of experimental autoimmune encephalomyelitis (EAE). However, pMHCII-CAR enhancements to pMHCII stability, as well as increased survivability via overexpression of a dominant-negative Fas, were required to target lower-affinity MOG-specific T cells and reverse ongoing clinical EAE. Thus, these data suggest a model in which higher-affinity autoreactive T cells are required to provide the "activation energy" for initiating neuroinflammatory injury, but lower-affinity cells are sufficient to maintain ongoing disease.

[Preliminary clinical effect evaluation of digital head and neck radiotherapy oral positioning stents]

Objective: To develop a designing software of digital oral positioning stent for radiotherapy of head and neck, and to compare its clinical effect with traditional oral positioning stents made by lost wax process. Methods: Thirty patients with nasopharyngeal cancer who received oral examination before radiotherapy in the prosthodontics department from July to December, 2021, were selected and divided into three groups according to the patients' wishes, 10 per group: one group without radiotherapy oral positioning stents, one group with traditional oral positioning stents (traditional stents group), and the third group with digital oral positioning stents (digital stents group). Patients' ages range from 20 years old to 71 years old. There were 15 males and 15 females involved in this study. The manufacturing time and comfort of the two positioning stents were evaluated, and the radiation doses of the radiotherapy target areas and surrounding healthy tissues were statistically analyzed at the end of radiotherapy. Results: The manufacturing time of digital stents group [(209±7) min] was much less than that of traditional stents group [(490±10) min] (t=69.85, P<0.001). The comfort of patients' wearing of digital stents [first wearing: 5 (3, 6) score; at the end of radiotherapy: 4 (3, 5) score] was better than that of traditional ones [first wearing: 7 (3, 7) score; at the end of radiotherapy: 7 (3, 7) score] (U=22.00, P=0.033; U=20.50, P=0.023). There was no significant differences in the target radiation doses among the three groups, and the radiation doses of tongue [traditional stents group: (36.74±5.45) Gy; digital stents group: (35.96±4.98) Gy] and mandible [traditional stents group: (35.46±4.19) Gy; digital stents group: (35.34±3.98) Gy] were significantly lower in the patients wearing oral positioning stents than in the patients without oral positioning stents [tongue: (41.49±4.46) Gy; madible: (39.32±3.52) Gy] (P<0.05). Conclusions: Oral positioning stents for nasopharyngeal carcinoma radiotherapy could greatly reduce the exposure doses of tongue and madible of patients. Digital oral positioning stents designed and manufactured by independently developed software had higher production efficiency than the traditional method, and patients' evaluation of comfort was better.

Miswiring of Merkel cell and pruriceptive C fiber drives the itch-scratch cycle

Itch sensation provokes the scratch reflex to protect us from harmful stimuli in the skin. Although scratching transiently relieves acute itch through activation of mechanoreceptors, it propagates the vicious itch-scratch cycle in chronic itch by further aggravating itch over time. Although well recognized clinically, the peripheral mechanisms underlying the itch-scratch cycle remain poorly understood. Here, we show that mechanical stimulation of the skin results in activation of the Piezo2 channels on Merkel cells that pathologically promotes spontaneous itch in experimental dry skin. Three-dimensional reconstruction and immunoelectron microscopy revealed structural alteration of MRGPRA3⁺ pruriceptor nerve endings directed toward Merkel cells in the setting of dry skin. Our results uncover a functional miswiring mechanism under pathologic conditions, resulting in touch receptors triggering the firing of pruriceptors in the skin to drive the itch-scratch cycle.

Targeting IFN-λ Signaling Promotes Recovery from Central Nervous System Autoimmunity

Type III IFNs (IFNLs) are newly discovered cytokines, acting at epithelial and other barriers, that exert immunomodulatory functions in addition to their primary roles in antiviral defense. In this study, we define a role for IFNLs in maintaining autoreactive T cell effector function and limiting recovery in a murine model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis. Genetic or Ab-based neutralization of the IFNL receptor (IFNLR) resulted in lack of disease maintenance during experimental autoimmune encephalomyelitis, with loss of CNS Th1 effector responses and limited axonal injury. Phenotypic effects of IFNLR signaling were traced to increased APC function, with associated increase in T cell production of IFN-γ and GM-CSF. Consistent with this, IFNL levels within lesions of CNS tissues derived from patients with MS were elevated compared with MS normal-appearing white matter. Furthermore, expression of IFNLR was selectively elevated in MS active lesions compared with inactive lesions or normal-appearing white matter. These findings suggest IFNL signaling as a potential therapeutic target to prevent chronic autoimmune neuroinflammation.

Reduced antibody activity against SARS-CoV-2 B.1.617.2 delta virus in serum of mRNA-vaccinated individuals receiving tumor necrosis factor-α inhibitors

BACKGROUND

Although vaccines effectively prevent coronavirus disease 2019 (COVID-19) in healthy individuals, they appear to be less immunogenic in individuals with chronic inflammatory disease (CID) or receiving chronic immunosuppression therapy.

METHODS

Here we assessed a cohort of 77 individuals with CID treated as monotherapy with chronic immunosuppressive drugs for antibody responses in serum against historical and variant severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viruses after immunization with the BNT162b2 mRNA vaccine.

FINDINGS

Longitudinal analysis showed the greatest reductions in neutralizing antibodies and Fc effector function capacity in individuals treated with tumor necrosis factor alpha (TNF-α) inhibitors (TNFi), and this pattern appeared to be worse against the B.1.617.2 delta virus. Within 5 months of vaccination, serum neutralizing titers of all TNFi-treated individuals tested fell below the presumed threshold correlate for antibody-mediated protection. However, TNFi-treated individuals receiving a third mRNA vaccine dose boosted their serum neutralizing antibody titers by more than 16-fold.

CONCLUSIONS

Vaccine boosting or administration of long-acting prophylaxis (e.g., monoclonal antibodies) will likely be required to prevent SARS-CoV-2 infection in this susceptible population.

FUNDING

This study was supported by grants and contracts from the NIH (R01 AI157155, R01AI151178, and HHSN75N93019C00074; NIAID Centers of Excellence for Influenza Research and Response (CEIRR) contracts HHSN272201400008C and 75N93021C00014; and Collaborative Influenza Vaccine Innovation Centers [CIVIC] contract 75N93019C00051).

Effect of Immunosuppression on the Immunogenicity of mRNA Vaccines to SARS-CoV-2 : A Prospective Cohort Study

BACKGROUND

Patients with chronic inflammatory disease (CID) treated with immunosuppressive medications have increased risk for severe COVID-19. Although mRNA-based SARS-CoV-2 vaccination provides protection in immunocompetent persons, immunogenicity in immunosuppressed patients with CID is unclear.

OBJECTIVE

To determine the immunogenicity of mRNA-based SARS-CoV-2 vaccines in patients with CID.

DESIGN

Prospective observational cohort study.

SETTING

Two U.S. CID referral centers.

PARTICIPANTS

Volunteer sample of adults with confirmed CID eligible for early COVID-19 vaccination, including hospital employees of any age and patients older than 65 years. Immunocompetent participants were recruited separately from hospital employees. All participants received 2 doses of mRNA vaccine against SARS-CoV-2 between 10 December 2020 and 20 March 2021. Participants were assessed within 2 weeks before vaccination and 20 days after final vaccination.

MEASUREMENTS

Anti-SARS-CoV-2 spike (S) IgG⁺ binding in all participants, and neutralizing antibody titers and circulating S-specific plasmablasts in a subset to assess humoral response after vaccination.

RESULTS

Most of the 133 participants with CID (88.7%) and all 53 immunocompetent participants developed antibodies in response to mRNA-based SARS-CoV-2 vaccination, although some with CID developed numerically lower titers of anti-S IgG. Anti-S IgG antibody titers after vaccination were lower in participants with CID receiving glucocorticoids (n = 17) than in those not receiving them; the geometric mean of anti-S IgG antibodies was 357 (95% CI, 96 to 1324) for participants receiving prednisone versus 2190 (CI, 1598 to 3002) for those not receiving it. Anti-S IgG antibody titers were also lower in those receiving B-cell depletion therapy (BCDT) (n = 10). Measures of immunogenicity differed numerically between those who were and those who were not receiving antimetabolites (n = 48), tumor necrosis factor inhibitors (n = 39), and Janus kinase inhibitors (n = 11); however, 95% CIs were wide and overlapped. Neutralization titers seemed generally consistent with anti-S IgG results. Results were not adjusted for differences in baseline clinical factors, including other immunosuppressant therapies.

LIMITATIONS

Small sample that lacked demographic diversity, and residual confounding.

CONCLUSION

Compared with nonusers, patients with CID treated with glucocorticoids and BCDT seem to have lower SARS-CoV-2 vaccine-induced antibody responses. These preliminary findings require confirmation in a larger study.

PRIMARY FUNDING SOURCE

The Leona M. and Harry B. Helmsley Charitable Trust, Marcus Program in Precision Medicine Innovation, National Center for Advancing Translational Sciences, and National Institute of Arthritis and Musculoskeletal and Skin Diseases.

In Vitro and In Vivo Investigation of S1PR1 Expression in the Central Nervous System Using [3H]CS1P1 and [11C]CS1P1

Sphingosine-1-phosphate receptor 1 (S1PR1) is ubiquitously expressed among all tissues and plays key roles in many physiological and cellular processes. In the central nervous system (CNS), S1PR1 is expressed in different types of cells including neurons, astrocytes, and oligodendrocyte precursor cells. S1PR1 has been recognized as a novel therapeutic target in multiple sclerosis and other diseases. We previously reported a promising S1PR1-specific radioligand, [¹¹C]CS1P1 (previously named [¹¹C]TZ3321), which is under clinical investigation for human use. In the current study, we performed a detailed characterization of [³H]CS1P1 for its binding specificity to S1PR1 in CNS using autoradiography and immunohistochemistry in human and rat CNS tissues. Our data indicate that [³H]CS1P1 binds to S1PR1 in human frontal cortex tissue with a K_d of 3.98 nM and a B_max of 172.5 nM. The distribution of [³H]CS1P1 in human and rat CNS tissues is consistent with the distribution of S1PR1 detected by immunohistochemistry studies. Our microPET studies of [¹¹C]CS1P1 in a nonhuman primate (NHP) show a standardized uptake value of 2.4 in the NHP brain, with test-retest variability of 0.23% among six different NHPs. Radiometabolite analysis in the plasma samples of NHP and rat, as well as in rat brain samples, showed that [¹¹C]CS1P1 was stable in vivo. Kinetic modeling studies using a two-compartment tissue model showed that the positron emission tomography (PET) data fit the model well. Overall, our study provides a detailed characterization of [³H]CS1P1 binding to S1PR1 in the CNS. Combined with our microPET studies in the NHP brain, our data suggest that [¹¹C]CS1P1 is a promising radioligand for PET imaging of S1PR1 in the CNS.

The Role of B Cells in Primary Progressive Multiple Sclerosis

The success of ocrelizumab in reducing confirmed disability accumulation in primary progressive multiple sclerosis (PPMS) via CD20-targeted depletion implicates B cells as causal agents in the pathogenesis of PPMS. This review explores the possible mechanisms by which B cells contribute to disease progression in PPMS, specifically exploring cytokine production, antigen presentation, and antibody synthesis. B cells may contribute to disease progression in PPMS through cytokine production, specifically GM-CSF and IL-6, which can drive naïve T-cell differentiation into pro-inflammatory Th1/Th17 cells. B cell production of the cytokine LT-α may induce follicular dendritic cell production of CXCL13 and lead indirectly to T and B cell infiltration into the CNS. In contrast, production of IL-10 by B cells likely induces an anti-inflammatory effect that may play a role in reducing neuroinflammation in PPMS. Therefore, reduced production of IL-10 may contribute to disease worsening. B cells are also capable of potent antigen presentation and may induce pro-inflammatory T-cell differentiation via cognate interactions. B cells may also contribute to disease activity via antibody synthesis, although it's unlikely the benefit of ocrelizumab in PPMS occurs via antibody decrement. Finally, various B cell subsets likely promulgate pro- or anti-inflammatory effects in MS.

Heterogeneity of meningeal B cells reveals a lymphopoietic niche at the CNS borders

The meninges contain adaptive immune cells that provide immunosurveillance of the central nervous system (CNS). These cells are thought to derive from the systemic circulation. Through single-cell analyses, confocal imaging, bone marrow chimeras, and parabiosis experiments, we show that meningeal B cells derive locally from the calvaria, which harbors a bone marrow niche for hematopoiesis. B cells reach the meninges from the calvaria through specialized vascular connections. This calvarial-meningeal path of B cell development may provide the CNS with a constant supply of B cells educated by CNS antigens. Conversely, we show that a subset of antigen-experienced B cells that populate the meninges in aging mice are blood-borne. These results identify a private source for meningeal B cells, which may help maintain immune privilege within the CNS.

[Effects of pressure steam sterilization times on the accuracy of the digital intraoral scanning data]

Objective: To provide a scientific basis for the standardized operation of clinical disinfection by comparing and analyzing the influence of disinfection times on the accuracy of digital intraoral scanning. Methods: The author prepared 10 brand-new intraoral scanning heads (Trios, 3Shape, Denmark), scan the same plaster standard dentition model after 1, 20, 40, and 60 times of pressure steam sterilization, and obtained the data of four groups of experimental groups A, B, C, D, and scan the model 5 times repeatedly after each disinfection cycle of each scanning head. A model scanner (D2000, 3Shape, Denmark) was used to scan the standard dentition model, and the scan results were used as the control group data. Vernier calipers and measurement software were used to measure the arch length (the distance between the mesial cheek tips of the first molars on both sides of the maxillary) and the front and back length (the distance from the tongue protrusion of the right incisor to the buccal tip of the first molar on the right of the upper jaw) of the plaster model and the data of the 4 experimental groups. The line distance results of the 4 groups of experimental groups were compared for statistical analysis, and the trueness and precision values of the 4 groups of experimental groups were compared for statistical analysis. Results: The length of the arch across the 4 experimental groups increased with the increase in the number of disinfection (P<0.05), and there were statistical differences compared with the measurement results of the plaster model (P<0.05); the differences in the length of the dental arch were not statistically significant (P>0.05). The treness of the 4 experimental groups is statistically significant (P<0.05), and the trueness was from high to low in order of group A [(114.85±3.75) μm], group B [(124.65±3.85) μm], group C [(131.45±3.04) μm] and group D [(144.64±3.34) μm]; the precision of the 4 experimental groups was not statistically significant (P>0.05). Conclusions: The number of times of pressure steam sterilization can affect the accuracy of the scanning results of the digital intraoral scanner, and with the increase of the number of sterilizations, the error of the scanning results also tends to increase. The number of sterilizations has no effect on the repeatability of the digital scanning results. The increase in the number of times of pressure steam sterilization affects the accross of the arch but has no effect on the length of the dental arch, and the range of change of the length of the arch is within the clinically acceptable range. After 60 times of pressure steam sterilization, the accuracy of digital scan data can still meet clinical needs.

Central vein sign and other radiographic features distinguishing myelin oligodendrocyte glycoprotein antibody disease from multiple sclerosis and aquaporin-4 antibody-positive neuromyelitis optica

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody disease (MOGAD) can radiographically mimic multiple sclerosis (MS) and aquaporin-4 (AQP4) antibody-positive neuromyelitis optica spectrum disorder (NMOSD). Central vein sign (CVS) prevalence has not yet been well-established in MOGAD.

OBJECTIVE

Characterize the magnetic resonance imaging (MRI) appearance and CVS prevalence of MOGAD patients in comparison to matched cohorts of MS and AQP4+ NMOSD.

METHODS

Clinical MRIs from 26 MOGAD patients were compared to matched cohorts of MS and AQP4+ NMOSD. Brain MRIs were assessed for involvement within predefined regions of interest. CVS was assessed by overlaying fluid-attenuated inversion recovery (FLAIR) and susceptibility-weighted sequences. Topographic analyses were performed on spinal cord and orbital MRIs when available.

RESULTS

MOGAD patients had fewer brain lesions and average CVS+ rate of 12.1%, compared to 44.4% in MS patients (p = 0.0008). MOGAD spinal cord and optic nerve involvement was lengthier than MS (5.8 vs 1.0 vertebral segments, p = 0.020; 3.0 vs 0.5 cm, p < 0.0001). MOGAD patients tended to have bilateral/anterior optic nerve pathology with perineural contrast enhancement, contrasting with posterior optic nerve involvement in NMOSD.

CONCLUSION

CVS+ rate and longer segments of involvement in the spinal cord and optic nerve can differentiate MOGAD from MS, but do not discriminate as well between MOGAD and AQP4+ NMOSD.

Glucocorticoids and B Cell Depleting Agents Substantially Impair Immunogenicity of mRNA Vaccines to SARS-CoV-2

BACKGROUND

Individuals with chronic inflammatory diseases (CID) are frequently treated with immunosuppressive medications that can increase their risk of severe COVID-19. While novel mRNA-based SARS-CoV-2 vaccination platforms provide robust protection in immunocompetent individuals, the immunogenicity in CID patients on immunosuppression is not well established. Therefore, determining the effectiveness of SARS-CoV-2 vaccines in the setting of immunosuppression is essential to risk-stratify CID patients with impaired protection and provide clinical guidance regarding medication management.

METHODS

We conducted a prospective assessment of mRNA-based vaccine immunogenicity in 133 adults with CIDs and 53 immunocompetent controls. Blood from participants over 18 years of age was collected before initial immunization and 1-2 weeks after the second immunization. Serum anti-SARS-CoV-2 spike (S) IgG + binding, neutralizing antibody titers, and circulating S-specific plasmablasts were quantified to assess the magnitude and quality of the humoral response following vaccination.

RESULTS

Compared to immunocompetent controls, a three-fold reduction in anti-S IgG titers (P=0.009) and SARS-CoV-2 neutralization (p<0.0001) were observed in CID patients. B cell depletion and glucocorticoids exerted the strongest effect with a 36- and 10-fold reduction in humoral responses, respectively (p<0.0001). Janus kinase inhibitors and antimetabolites, including methotrexate, also blunted antibody titers in multivariate regression analysis (P<0.0001, P=0.0023, respectively). Other targeted therapies, such as TNF inhibitors, IL-12/23 inhibitors, and integrin inhibitors, had only modest impacts on antibody formation and neutralization.

CONCLUSIONS

CID patients treated with immunosuppressive therapies exhibit impaired SARS-CoV-2 vaccine-induced immunity, with glucocorticoids and B cell depletion therapy more severely impeding optimal responses.

cDC1 prime and are licensed by CD4+ T cells to induce anti-tumour immunity

Conventional type 1 dendritic cells (cDC1)1 are thought to perform antigen cross-presentation, which is required to prime CD8+ T cells2,3, whereas cDC2 are specialized for priming CD4+ T cells4,5. CD4+ T cells are also considered to help CD8+ T cell responses through a variety of mechanisms6-11, including a process whereby CD4+ T cells 'license' cDC1 for CD8+ T cell priming12. However, this model has not been directly tested in vivo or in the setting of help-dependent tumour rejection. Here we generated an Xcr1Cre mouse strain to evaluate the cellular interactions that mediate tumour rejection in a model requiring CD4+ and CD8+ T cells. As expected, tumour rejection required cDC1 and CD8+ T cell priming required the expression of major histocompatibility class I molecules by cDC1. Unexpectedly, early priming of CD4+ T cells against tumour-derived antigens also required cDC1, and this was not simply because they transport antigens to lymph nodes for processing by cDC2, as selective deletion of major histocompatibility class II molecules in cDC1 also prevented early CD4+ T cell priming. Furthermore, deletion of either major histocompatibility class II or CD40 in cDC1 impaired tumour rejection, consistent with a role for cognate CD4+ T cell interactions and CD40 signalling in cDC1 licensing. Finally, CD40 signalling in cDC1 was critical not only for CD8+ T cell priming, but also for initial CD4+ T cell activation. Thus, in the setting of tumour-derived antigens, cDC1 function as an autonomous platform capable of antigen processing and priming for both CD4+ and CD8+ T cells and of the direct orchestration of their cross-talk that is required for optimal anti-tumour immunity.

[Effects and mechanism of pyrroloquinoline quinine on mitochondrial function and cell survival of rat bone marrow mesenchymal stem cells under oxidative stress]

Objective: To observe the effects of pyrroloquinoline quinine (PQQ) on the mitochondrial function and cell survival of rat bone marrow mesenchymal stem cells (BMSCs) under oxidative stress, and to explore its mechanism. Methods: BMSCs of rats were cultured in vitro with Dulbecco's minimum essential medium/F12 medium containing fetal bovine serum in the volume fraction of 10% (hereinafter referred to as normal medium). The rat BMSCs of third to fifth passages in logarithmic growth phase were selected for the following experiments. (1) The cells were divided into normal control group, normal control+ PQQ group, hydrogen peroxide (H(2)O(2)) alone group, and H(2)O(2)+ PQQ group. The cells in normal control group were cultured in normal medium for 24 hours; the cells in normal control+ PQQ group were cultured in normal medium containing 100 μmol/L PQQ for 24 hours; the cells in H(2)O(2) alone group were cultured in normal medium containing 200 μmol/L H(2)O(2) for 24 hours; the cells in H(2)O(2)+ PQQ group were pre-incubated with normal medium containing 100 μmol/L PQQ for 2 hours, and then with H(2)O(2) added to the concentration of 200 μmol/L and cultured for 24 hours. The cell morphology of each group was observed under the inverted phase contrast microscope, and the cell survival rate was detected by cell count kit 8 method. (2) Five batches of cells were collected, and the cells of each batch were divided into normal control group, H(2)O(2) alone group, and H(2)O(2)+ PQQ group. The cells in each group received the same treatment as that in the corresponding group of experiment (1). After 24 hours of culture, one batch of cells was collected for apoptosis detection by flow cytometry, and the apoptosis rate was calculated. One batch of cells was subjected to mitochondrial membrane potential assay and JC-1 fluorescent staining observation using the JC-1 mitochondrial membrane potential detection kit and the inverted phase contrast fluorescence microscope, respectively. One batch of cells was collected for mitochondrial morphology observation under the transmission electron microscope. One batch of cells was subjected to catalase (CAT) and superoxide dismutase (SOD) activity assay by CAT activity assay kit and SOD activity assay kit, respectively. One batch of cells was subjected to Western blotting for determination of protein level of Epac1, adenine monophosphate activated protein kinase (AMPK), phosphorylated AMPK, cysteinyl aspartate-specific proteinase 3 (caspase-3), and cleaved caspase-3, and the phosphorylation level of AMPK and cleaved caspase-3/caspase-3 ratio were calculated. Six replicates were measured in each group for each index except for morphological observation. Data were statistically analyzed with one-way analysis of variance and independent sample equal variance t test. Results: (1) After 24 hours of culture, compared with those in normal control group (the cell survival rate was set to 100.0%), there was an increase in cell vacuole and a decrease in cell number in H(2)O(2) alone group, and the cell survival rate was significantly reduced to (74.3±2.9)% (t=6.39, P<0.01). Compared with those in H(2)O(2) alone group, the cell morphology of H(2)O(2)+ PQQ group was significantly improved, and the cell survival rate was significantly increased to (116.9±4.2)% (t=6.92, P<0.01); the cell survival rate in normal control+ PQQ group was (101.2±1.1)%, close to that of control group (t=1.06, P>0.05). (2) After 24 hours of culture, compared with (13.6±1.0)% in normal control group, the apoptosis rate of cells in H(2)O(2) alone group was significantly increased to (37.1±2.0)% (t=10.57, P<0.01). Compared with that in H(2)O(2) alone group, the apoptosis rate of cells in H(2)O(2)+ PQQ group was significantly declined to (17.0±0.7)% (t=9.49, P<0.01). (3) After 24 hours of culture, compared with those in normal control group, the mitochondrial membrane potential of cells in H(2)O(2) alone group was depolarized, the JC-1 fluorescent dye mainly existed in the cytoplasm in the form of monomer, which emitted green fluorescence, and a significant decrease in mitochondrial membrane potential was shown (t=4.18, P<0.01). Compared with those in H(2)O(2) alone group, the mitochondrial membrane potential of cells in H(2)O(2)+ PQQ group was increased to normal level (t=4.43, P<0.01), and the JC-1 fluorescent dye accumulated in mitochondria following the polarized mitochondrial membrane potential and emitted red fluorescence. (4) After 24 hours of culture, compared with that in normal control group, the mitochondrial structure of cells in H(2)O(2) alone group was disordered, with disappeared mitochondrial cristae and decreased mitochondrial matrix density. Compared with that in H(2)O(2) alone group, the mitochondrial structure of cells in H(2)O(2)+ PQQ group was regular and intact, with clearly visible mitochondrial cristae and increased mitochondrial matrix density. (5) After 24 hours of culture, compared with those in normal control group, the CAT activity of cells in H(2)O(2) alone group was significantly increased (t=4.54, P<0.05), and the SOD activity was significantly decreased (t=3.93, P<0.05). Compared with those in H(2)O(2) alone group, the CAT activity of cells in H(2)O(2)+ PQQ group was obviously increased (t=8.65, P<0.01), while there was no significant change in the SOD activity (t=0.72, P>0.05). (6) After 24 hours of culture, compared with those in normal control group, the protein expression of Epac1 of cells in H(2)O(2) alone group was significantly decreased (t=4.67, P<0.01), while the AMPK phosphorylation level and the cleaved caspase-3/caspase-3 ratio were significantly increased (t=7.88, 3.62, P<0.01). Compared with those in H(2)O(2) alone group, the protein expression of Epac1 and the AMPK phosphorylation level of cells in H(2)O(2)+ PQQ group were both significantly increased (t=4.34, 16.37, P<0.01), while the cleaved caspase-3/caspase-3 ratio was significantly declined (t=3.17, P<0.05). Conclusions: Pretreatment with PQQ can improve the mitochondrial function, reduce cell apoptosis rate, and enhance cell survival rate of rat BMSCs under oxidative stress, which may be related to the up-regulation of Epac1 protein expression, activation of AMPK signaling pathway, and down-regulation of cleaved caspase-3 protein level.

Clinical and laboratory features distinguishing MOG antibody disease from multiple sclerosis and AQP4 antibody-positive neuromyelitis optica

BACKGROUND

Antibodies to myelin oligodendrocyte glycoprotein (MOG) are associated with a CNS inflammatory disorder distinct from multiple sclerosis (MS) and aquaporin-4 antibody-positive neuromyelitis optica (NMO). Knowledge of the clinical spectrum of MOG antibody disease (MOGAD) remains incomplete, particularly in comparison to two related inflammatory demyelinating diseases, MS and NMO.

OBJECTIVE

Compare demographics, clinical characteristics, estimated disability, laboratory results, and treatment responses of a U.S. MOGAD cohort with age- and sex-matched MS and NMO patients.

DESIGN, SETTING, AND PARTICIPANTS

This observational, case-control, single-center study identified each group via ICD-10 diagnosis code searches through the electronic medical records of adult patients seen at the John L. Trotter MS Center between January 1, 2019 and January 1, 2020. MOGAD and NMO patients were confirmed to have at least one positive antibody test; those in the MS group had a confirmed diagnosis by a physician with MS subspecialty training. Data were collected after IRB approval.

RESULTS

Twenty-six patients were included in each group. MOGAD patients were predominantly Caucasian (88.5%) with mean onset age of 43.9 years. MOGAD patients had no comorbid other autoimmune diseases and comparatively lower rates of family members with autoimmune disease (20.0%) than either MS (40.0%) or NMO (34.6%) matched cohorts. 91% of MOGAD attacks were monofocal, and over 70% presented with optic neuritis. Severity of MOGAD attacks was similar to that of seropositive NMO, but the robust degree of recovery was more similar to MS. Four MOGAD patients converted to negative antibody status, with no attacks occurring after conversion. Serum ANA and ENA were less frequently elevated in MOGAD (21.7%, 5.0%) than in seropositive NMO patients (66.7%, 42.9%). Elevated IgG synthesis rate and positive CSF-restricted oligoclonal bands were not seen in our MOGAD cohort, and only one MOGAD patient had an elevated IgG index. Despite anti-CD20 therapy, 28.6% of MOGAD patients continued to suffer relapses.

CONCLUSIONS

MOGAD was characterized by a predominantly monofocal presentation (typically optic neuritis) and severe attacks with better recovery than seen with seropositive NMO attacks. Lack of CSF-restricted oligoclonal bands distinguished MOGAD from MS.

Mindfulness, Education, and Exercise for age-related cognitive decline: Study protocol, pilot study results, and description of the baseline sample

BACKGROUND/AIMS

Age-related cognitive decline is a pervasive problem in our aging population. To date, no pharmacological treatments to halt or reverse cognitive decline are available. Behavioral interventions, such as physical exercise and Mindfulness-Based Stress Reduction, may reduce or reverse cognitive decline, but rigorously designed randomized controlled trials are needed to test the efficacy of such interventions.

METHODS

Here, we describe the design of the Mindfulness, Education, and Exercise study, an 18-month randomized controlled trial that will assess the effect of two interventions-mindfulness training plus moderate-to-vigorous intensity exercise or moderate-to-vigorous intensity exercise alone-compared with a health education control group on cognitive function in older adults. An extensive battery of biobehavioral assessments will be used to understand the mechanisms of cognitive remediation, by using structural and resting state functional magnetic resonance imaging, insulin sensitivity, inflammation, and metabolic and behavioral assessments.

RESULTS

We provide the results from a preliminary study (n = 29) of non-randomized pilot participants who received both the exercise and Mindfulness-Based Stress Reduction interventions. We also provide details on the recruitment and baseline characteristics of the randomized controlled trial sample (n = 585).

CONCLUSION

When complete, the Mindfulness, Education, and Exercise study will inform the research community on the efficacy of these widely available interventions improve cognitive functioning in older adults.

Single-cell RNA-seq analysis of human CSF microglia and myeloid cells in neuroinflammation

Objective

To identify and characterize myeloid cell populations within the CSF of patients with MS and anti-myelin oligodendrocyte glycoprotein (MOG) disorder by high-resolution single-cell gene expression analysis.

Methods

Single-cell RNA sequencing (scRNA-seq) was used to profile individual cells of CSF and blood from 2 subjects with relapsing-remitting MS (RRMS) and one with anti-MOG disorder. Publicly available scRNA-seq data from the blood and CSF of 2 subjects with HIV were also analyzed. An informatics pipeline was used to cluster cell populations by transcriptomic profiling. Based on gene expression by CSF myeloid cells, a flow cytometry panel was devised to examine myeloid cell populations from the CSF of 11 additional subjects, including individuals with RRMS, anti-MOG disorder, and control subjects without inflammatory demyelination.

Results

Common myeloid populations were identified within the CSF of subjects with RRMS, anti-MOG disorder, and HIV. These included monocytes, conventional and plasmacytoid dendritic cells, and cells with a transcriptomic signature matching microglia. Microglia could be discriminated from other myeloid cell populations in the CSF by flow cytometry.

Conclusions

High-resolution single-cell gene expression analysis clearly distinguishes distinct myeloid cell types present within the CSF of subjects with neuroinflammation. A population of microglia exists within the human CSF, which is detectable by surface protein expression. The function of these cells during immunity and disease requires further investigation.

X-tra X: An escape to autoimmunity

Identifying the factors driving disease disparities between males and females with multiple sclerosis (MS) holds great promise for deciphering immunopathogenic disease mechanisms. In this issue of JCI, Itoh et al. explore the basis for sexual dimorphism in autoimmunity, specifically in MS. Using the experimental autoimmune encephalomyelitis (EAE) model of MS, which recapitulates CD4+ T cell-dependent disease, the authors examined the contribution of Kdm6a, a histone demethylase gene known to escape X inactivation. Conditional knockout in CD4+ T cells revealed Kdm6a involvement with a collection of immunologic processes having the potential to skew immunity toward inflammatory responses. This study concisely shows the value of X chromosome gene expression in T cell regulation of autoimmunity and the relevance of Kdm6a in the pathogenesis of EAE as a model of MS.

B Cell-Mediated Antigen Presentation through MHC Class II Is Dispensable for Atherosclerosis Progression

Depletion of B cells attenuates plaque development and modulates T cell responses in mouse models of atherosclerosis, suggesting that Ag presentation by B cells may promote disease progression. Thus, we set out to determine the role of B cell-mediated MHC class II (MHC II) Ag presentation during atherosclerotic plaque development. We developed murine conditional MHC II deletion and expression systems under control of the B cell-restricted CD19 promoter in an experimental model of atherosclerosis. Mice lacking MHC II expression only on B cells exhibited systemic shifts in germinal center and marginal zone B cell populations, leading to a reduced Ab response compared with littermate control animals. However, all populations were present and normal cholesterol uptake was detected in the plasma following high-fat diet treatment. In a second model, in which conditional expression of MHC II is limited only to B cells, showed similar overall cellularity characteristics compared with mice with complete MHC II deficiency. High-fat diet feeding showed no major changes in atherosclerotic plaque size or plaque cellular content in either conditional deletion or conditional expression approaches, compared with control animals. By testing the necessity and sufficiency of MHC II on B cells in the progression of atherosclerosis, we determine that MHC II on B cells does not directly regulate lesion development in murine models.

MicroRNA signature of central nervous system-infiltrating dendritic cells in an animal model of multiple sclerosis

Innate immune cells are integral to the pathogenesis of several diseases of the central nervous system (CNS), including multiple sclerosis (MS). Dendritic cells (DCs) are potent CD11c+ antigen-presenting cells that are critical regulators of adaptive immune responses, particularly in autoimmune diseases such as MS. The regulation of DC function in both the periphery and CNS compartment has not been fully elucidated. One limitation to studying the role of CD11c+ DCs in the CNS is that microglia can upregulate CD11c during inflammation, making it challenging to distinguish bone marrow-derived DCs (BMDCs) from microglia. Selective expression of microRNAs (miRNAs) has been shown to distinguish populations of innate cells and regulate their function within the CNS during neuro-inflammation. Using the experimental autoimmune encephalomyelitis (EAE) murine model of MS, we characterized the expression of miRNAs in CD11c+ cells using a non-biased murine array. Several miRNAs, including miR-31, were enriched in CD11c+ cells within the CNS during EAE, but not LysM+ microglia. Moreover, to distinguish CD11c+ DCs from microglia that upregulate CD11c, we generated bone marrow chimeras and found that miR-31 expression was specific to BMDCs. Interestingly, miR-31-binding sites were enriched in mRNAs downregulated in BMDCs that migrated into the CNS, and a subset was confirmed to be regulated by miR-31. Finally, miR-31 was elevated in DCs migrating through an in vitro blood-brain barrier. Our findings suggest miRNAs, including miR-31, may regulate entry of DCs into the CNS during EAE, and could potentially represent therapeutic targets for CNS autoimmune diseases such as MS.

A case of oligodendroglioma and multiple sclerosis: Occam's razor or Hickam's dictum?

Tumefactive appearing lesions on brain imaging can cause a diagnostic dilemma. We report a middle-aged man who presented with right-sided optic neuritis. A brain MRI showed enhancement of the right optic nerve, and non-enhancing white matter lesions including a 3 cm right frontal lesion with adjacent gyral expansion. Cerebrospinal fluid analysis showed five oligoclonal bands not present in serum. Glatiramer acetate was started for suspected tumefactive multiple sclerosis (MS). A follow-up brain MRI 6 months later showed persistence of the frontal gyral expansion. A brain biopsy led to the diagnosis of an oligodendroglioma, isocitrate dehydrogenase-mutant and 1 p/19q co-deleted (WHO grade II), managed with surgical resection and radiotherapy. Postoperative brain MRI showed a new enhancing periventricular lesion, making the choice of optimal disease-modifying therapy for MS challenging. This case highlights the possibility of coexistence of MS and oligodendroglioma, and emphasises the importance of a tissue diagnosis when atypical MS imaging features are present.

B cells are capable of independently eliciting rapid reactivation of encephalitogenic CD4 T cells in a murine model of multiple sclerosis

Recent success with B cell depletion therapies has revitalized efforts to understand the pathogenic role of B cells in Multiple Sclerosis (MS). Using the adoptive transfer system of experimental autoimmune encephalomyelitis (EAE), a murine model of MS, we have previously shown that mice in which B cells are the only MHCII-expressing antigen presenting cell (APC) are susceptible to EAE. However, a reproducible delay in the day of onset of disease driven by exclusive B cell antigen presentation suggests that B cells require optimal conditions to function as APCs in EAE. In this study, we utilize an in vivo genetic system to conditionally and temporally regulate expression of MHCII to test the hypothesis that B cell APCs mediate attenuated and delayed neuroinflammatory T cell responses during EAE. Remarkably, induction of MHCII on B cells following the transfer of encephalitogenic CD4 T cells induced a rapid and robust form of EAE, while no change in the time to disease onset occurred for recipient mice in which MHCII is induced on a normal complement of APC subsets. Changes in CD4 T cell activation over time did not account for more rapid onset of EAE symptoms in this new B cell-mediated EAE model. Our system represents a novel model to study how the timing of pathogenic cognate interactions between lymphocytes facilitates the development of autoimmune attacks within the CNS.

VLA4 expression by B cells enables B cell-restricted antigen presentation to support CD4 T cell driven central nervous system autoimmunity

Clonal expansion along with immunoglobulin (Ig) class-switching and secretion result from B cell antigen presentation to cognate CD4 T cells. The presence of oligoclonal Ig in the cerebrospinal fluid of most patients with multiple sclerosis raises the important question of where cognate B:T cell interactions occurs during disease. Previously we showed that increasing the frequency of MOG-specific B cells is sufficient to drive EAE in mice expressing MHCII solely by B cells. We have now established a system in which EAE reliably occurs upon expression of MHCII using Tamoxifen-induced temporal regulation in MOG-specific B cells. While B cells express MHCII in the central nervous system (CNS) in these models, whether or not B cells acquire and present antigen in the CNS compartment is unknown. Large clusters of B cells rapidly formed in the subarachnoid space of the spinal cord during EAE in our model, suggesting homing to the CNS is important for antigen presentation. Genetic regulation of B cell MOG-specificity and expression of MHCII and Very Late Antigen-4 (VLA-4) was used to determine the dependence of passive EAE susceptibility on B cell access to the CNS. Mice in which VLA-4 expression was abrogated simultaneously with MHCII expression by MOG-specific B cells were subjected to passive EAE. Disease exclusively mediated by B cell antigen presentation was dependent on VLA-4 expression by B cells. MOG-specific CD4 T cell hybridomas did not detect endogenous MOG presented by B cells harvested from the periphery of mice prior to the onset of disease. Taken together, our findings indicate that B cells require access to CNS myelin targets in order to propagate antigen-specific CD4 T cell-dependent neuro-inflammation.

Gray matter regions statistically mediating the cross-sectional association of eotaxin and set-shifting among older adults with major depressive disorder

OBJECTIVE

Eotaxin is a chemokine that exerts negative effects on neurogenesis. We recently showed that peripheral eotaxin levels correlate with both lower gray matter volume and poorer executive performance in older adults with major depressive disorder. These findings suggest that the relationship between eotaxin and set-shifting may be accounted for by lower gray matter volume in specific regions. Prior studies have identified specific gray matter regions that correlate with set-shifting performance, but have not examined whether these specific gray matter regions mediate the cross-sectional association between eotaxin and set-shifting.

METHOD

In 27 older adults (mean age: 68 ± 5.2 years) with major depressive disorder, we performed a whole brain (voxel-wise) analysis testing whether/where gray matter density statistically mediates the cross-sectional association of eotaxin and set-shifting performance.

RESULTS

We found the association between eotaxin and set-shifting performance was fully statistically mediated by lower gray matter density in left middle cingulate, right pre-/post-central, lingual, inferior/superior frontal, cuneus, and middle temporal regions.

CONCLUSION

The regions identified above may be both susceptible to a potential neurodegenerative effect of eotaxin, and critical to preserving set-shifting function. Longitudinal and intervention studies are needed to further evaluate whether targeting eotaxin levels will prevent neurodegeneration and executive impairment in older adults with depression. Copyright © 2016 John Wiley & Sons, Ltd.

Role of B cells in TH cell responses in a mouse model of asthma

BACKGROUND

The importance of B lymphocytes to present antigens for antibody production is well documented. In contrast, very little is known about their capacity to influence CD4⁺ T-cell activation during a primary or secondary response to allergens.

OBJECTIVE

Using mouse models of asthma, we investigated the role of B cells as antigen-presenting cells in priming and maintenance of T_H cell responses.

METHODS

Mice were immunized through the intranasal route with house dust mite (HDM) extract derived from Dermatophagoides pteronyssinus. B cells were depleted in HDM-sensitized animals to investigate the importance of B cells in maintenance of the allergic response. B cells were depleted before HDM sensitization to investigate the role of B cells in T-cell priming; furthermore, HDM sensitization was performed in mice with MHC class II expression restricted to the B-cell lineage.

RESULTS

We found that B cells serve as potent antigen-presenting cells ex vivo and restimulate in vivo-primed HDM-specific T_H cells. HDM antigens were taken up by B cells independently of B-cell receptor specificity, indicating that HDM uptake and antigen presentation to CD4⁺ T cells is not restricted to rare B cells carrying HDM-specific B cell receptors. B-cell depletion before HDM challenge in HDM-sensitized mice resulted in a dramatic reduction of allergic response, indicating the role of B cells in amplification of T_H2 responses. In contrast, HDM sensitization of mice in which MHC class II expression was restricted to B cells revealed the inability of these cells to prime T_H2 responses but highlighted their unexpected role in priming T_H1 and T_H17 responses.

CONCLUSION

Collectively, these data reveal new mechanisms leading to initiation and exacerbation of the allergic response that might have implications for designing new therapeutic strategies to combat HDM allergy.

[Effects of human amniotic epithelial stem cells-derived exosomes on healing of wound with full-thickness skin defect in rats]

Objective: To investigate the effects of human amniotic epithelial stem cells-derived exosomes on healing of wound with full-thickness skin defect in rats. Methods: (1) Human amniotic epithelial stem cells were isolated from the amnion tissue of 5 full-term pregnant women in Department of Obstetrics of our hospital by the method of trypsin digestion, and their morphology was observed. The third passage of cells were stained with rhodamine-phalloidin for cytoskeleton observation. The third passage of cells were identified with flow cytometry through the detection of expressions of cell surface markers CD29, CD31, CD34, CD90, CD105, SSEA3, SSEA4 and immunity-related marker human leukocyte antigen-D related site (HLA-DR). The third passage of cells were also assessed the ability of adipogenic and osteogenic differentiation. (2) The third passage of human amniotic epithelial stem cells were cultured in DMEM medium supplemented with 10% exosome-free fetal bovine serum. Exosomes were isolated from culture supernatant by the method of ultracentrifugation and represented with scanning electron microscope for morphologic observation. (3) Six adult SD rats were anesthetized, and four 1 cm×1 cm sized wounds with full-thickness skin defect were made on the back of each rat. The wounds on the back of each rat were divided into control group, 25 μg/mL exosomes group, 50 μg/mL exosomes group, and 100 μg/mL exosomes group according to the random number table (with 6 wounds in each group), and a total volume of 100 μL phosphate buffered saline, 25 μg/mL exosomes, 50 μg/mL exosomes, and 100 μg/mL exosomes were evenly injected around the wound through multiple subcutaneous sites, respectively. The wound healing rate was calculated based on measurement on post injury day (PID) 7, 14, and 21. On PID 21, the healed wound tissue of each group was collected and stained with HE to observe and count skin accessories, and the arrangement of collagen fibers was observed with Masson staining. Data were processed with analysis of variance for repeated measurement, analysis of variance of randomized block design, one-way analysis of variance, and Bonferroni test. Results: (1) The cells, which were isolated and cultured, displayed typical cobblestone morphology with many microvilli on cell surface. Among the cells, the positive expression rates of CD29, CD90, SSEA3, and SSEA4 were above 50.0%, and the rate of CD105 was 8.0%, while the rates of CD31, CD34, and HLA-DR were almost 0. The cells could differentiate into adipocytes and osteoblasts. The above results revealed that the cells cultured were human amniotic epithelial stem cells. (2) Human amniotic epithelial stem cells-derived exosomes were round or oval vesicles with diameter from 50 to 150 nm. (3) On PID 7 and 21, wound healing rates of the four groups were close (with P values above 0.05). On PID 14, wound healing rates of 50 and 100 μg/mL exosomes groups were (89.8±4.3)% and (92.0±4.6)% respectively, significantly higher than the wound healing rate of control group [(80.3±6.4)%, P<0.05 or P<0.01]. Moreover, the wound healing rate of 100 μg/mL exosomes group was significantly higher than that of 25 μg/mL exosomes group [(83.3±5.1)%, P<0.05]. On PID 21, the numbers of skin accessories in 50 and 100 μg/mL exosomes groups were 4.3±1.4 and 5.1±1.6 respectively, obviously more than those of control group and 25 μg/mL exosomes group (respectively 1.4±0.5 and 1.8±0.6, with P values below 0.01). Well reorganized collagen fibers were observed just in the healed wound tissue of 50 and 100 μg/mL exosomes groups. Conclusions: Human amniotic epithelial stem cells-derived exosomes can promote healing of wound with full-thickness skin defect in rats.

Immunological biomarkers associated with brain structure and executive function in late-life depression: exploratory pilot study

OBJECTIVE

Several immunological biomarkers are altered in late-life major depressive disorder (LLD). Immunological alterations could contribute to LLD's consequences, but little is known about the relations between specific immunological biomarkers and brain health in LLD. We performed an exploratory pilot study to identify, from several candidates, the specific immunological biomarkers related to important aspects of brain health that are altered in LLD (brain structure and executive function).

METHODS

Adults (n = 31) were at least 60 years old and had major depressive disorder. A multiplex immunoassay assessed 13 immunological biomarkers, and we examined their associations with structural MRI (grey matter volume and white matter hyperintensity volume (WMH)) and executive function (Color-Word Interference and Trail-Making tests) measures.

RESULTS

Vascular endothelial growth factor (VEGF) and the chemokine eotaxin had significant negative associations with grey matter volume (VEGF: n = 31, r = -0.65; eotaxin: n = 29, r = -0.44). Tumor necrosis factor alpha (TNF-α) had a significant positive relationship with WMHs (n = 30, r = 0.52); interferon-γ (IFN-γ) and macrophage inflammatory protein-1α (MIP-1α) were also significantly associated with WMHs (IFN-γ: n = 31, r = 0.48; MIP-1α: n = 29, r = 0.45). Only eotaxin was associated with executive function (set-shifting performance as measured with the Trail-making test: n = 33, r = -0.43).

CONCLUSIONS

Immunological markers are associated with brain structure in LLD. We found the immunological correlates of grey and white matter differ. Prospective studies are needed to evaluate whether these immunological correlates of brain health increase the risk of LLD's consequences. Eotaxin, which correlated with both grey matter volume and set-shifting performance, may be particularly relevant to neurodegeneration and cognition in LLD. Copyright © 2016 John Wiley & Sons, Ltd.

Skin-derived TSLP systemically expands regulatory T cells

Regulatory T cells (Tregs) are a subset of CD4⁺ T cells with suppressive function and are critical for limiting inappropriate activation of T cells. Hence, the expansion of Tregs is an attractive strategy for the treatment of autoimmune diseases. Here, we demonstrate that the skin possesses the remarkable capacity to systemically expand Treg numbers by producing thymic stromal lymphopoietin (TSLP) in response to vitamin D receptor stimulation. An ∼2-fold increase in the proportion and absolute number of Tregs was observed in mice treated topically but not systemically with the Vitamin D3 analog MC903. This expansion of Tregs was dependent on TSLP receptor signaling but not on VDR signaling in hematopoietic cells. However, TSLP receptor expression by Tregs was not required for their proliferation. Rather, skin-derived TSLP promoted Treg expansion through dendritic cells. Importantly, treatment of skin with MC903 significantly lowered the incidence of autoimmune diabetes in non-obese diabetic mice and attenuated disease score in experimental autoimmune encephalomyelitis. Together, these data demonstrate that the skin has the remarkable potential to control systemic immune responses and that Vitamin D-mediated stimulation of skin could serve as a novel strategy to therapeutically modulate the systemic immune system for the treatment of autoimmunity.

Mir-223 regulates the number and function of myeloid-derived suppressor cells in multiple sclerosis and experimental autoimmune encephalomyelitis

Myeloid-derived cells play important modulatory and effector roles in multiple sclerosis (MS) and its animal model, experimental autoimmune encephalomyelitis (EAE). Myeloid-derived suppressor cells (MDSCs) are immature myeloid cells, composed of monocytic (MO) and polymorphonuclear (PMN) fractions, which can suppress T cell activities in EAE. Their role in MS remains poorly characterized. We found decreased numbers of circulating MDSCs, driven by lower frequencies of the MO-MDSCs, and higher MDSC expression of microRNA miR-223 in MS versus healthy subjects. To gain mechanistic insights, we interrogated the EAE model. MiR-223 knock out (miR-223^-/-) mice developed less severe EAE with increased MDSC numbers in the spleen and spinal cord compared to littermate controls. MiR-223^-/- MO-MDSCs suppressed T cell proliferation and cytokine production in vitro and EAE in vivo more than wild-type MO-MDSCs. They also displayed an increased expression of critical mediators of MDSC suppressive function, Arginase-1(Arg1), and the signal transducer and activator of transcription 3 (Stat3), which herein, we demonstrate being an miR-223 target gene. Consistently, MDSCs from MS patients displayed decreased STAT3 and ARG1 expression compared with healthy controls, suggesting that circulating MDSCs in MS are not only reduced in numbers but also less suppressive. These results support a critical role for miR-223 in modulating MDSC biology in EAE and in MS and suggest potential novel therapeutic applications.

The contemporary spectrum of multiple sclerosis misdiagnosis: A multicenter study

OBJECTIVE

To characterize patients misdiagnosed with multiple sclerosis (MS).

METHODS

Neurologists at 4 academic MS centers submitted data on patients determined to have been misdiagnosed with MS.

RESULTS

Of 110 misdiagnosed patients, 51 (46%) were classified as "definite" and 59 (54%) "probable" misdiagnoses according to study definitions. Alternate diagnoses included migraine alone or in combination with other diagnoses 24 (22%), fibromyalgia 16 (15%), nonspecific or nonlocalizing neurologic symptoms with abnormal MRI 13 (12%), conversion or psychogenic disorders 12 (11%), and neuromyelitis optica spectrum disorder 7 (6%). Duration of misdiagnosis was 10 years or longer in 36 (33%) and an earlier opportunity to make a correct diagnosis was identified for 79 patients (72%). Seventy-seven (70%) received disease-modifying therapy and 34 (31%) experienced unnecessary morbidity because of misdiagnosis. Four (4%) participated in a research study of an MS therapy. Leading factors contributing to misdiagnosis were consideration of symptoms atypical for demyelinating disease, lack of corroborative objective evidence of a CNS lesion as satisfying criteria for MS attacks, and overreliance on MRI abnormalities in patients with nonspecific neurologic symptoms.

CONCLUSIONS

Misdiagnosis of MS leads to unnecessary and potentially harmful risks to patients. Misinterpretation and misapplication of MS clinical and radiographic diagnostic criteria are important contemporary contributors to misdiagnosis.

Association analysis between carcass weight and meat quality of Bamei pigs

A total of 48 crossbred Bamei pig carcasses were divided into three groups (A, 60-69 kg; B, 70-79 kg; and C, 80-90 kg) to investigate the influence of carcass weight on meat quality. The intramuscular fat content of the three groups increased from 2.20% (Group A) to 4.14% (Group C). Group B had higher drip loss (6.83%, P < 0.05) than the other two groups. Warner-Bratzler shear force decreased with increasing weight (61.16 > 51.63 > 43.64 N, P < 0.05). No significant differences were observed in meat color, cooking percentage, and water holding capacity among the three groups. The polyunsaturated fatty acids/saturated fatty acids ratio in group B (0.23) was significantly higher than that in the other two groups. In conclusion, our results suggested that a carcass weight of 70-79 kg is suitable for the production of Bamei pigs.