Vascular Disease and Thrombosis in SARS-CoV-2-Infected Rhesus Macaques.

The COVID-19 pandemic has led to extensive morbidity and mortality throughout the world. Clinical features that drive SARS-CoV-2 pathogenesis in humans include inflammation and thrombosis, but the mechanistic details underlying these processes remain to be determined. In this study, we demonstrate endothelial disruption and vascular thrombosis in histopathologic sections of lungs from both humans and rhesus macaques infected with SARS-CoV-2. To define key molecular pathways associated with SARS-CoV-2 pathogenesis in macaques, we performed transcriptomic analyses of bronchoalveolar lavage and peripheral blood and proteomic analyses of serum. We observed macrophage infiltrates in lung and upregulation of macrophage, complement, platelet activation, thrombosis, and proinflammatory markers, including C-reactive protein, MX1, IL-6, IL-1, IL-8, TNFα, and NF-κB. These results suggest a model in which critical interactions between inflammatory and thrombosis pathways lead to SARS-CoV-2-induced vascular disease. Our findings suggest potential therapeutic targets for COVID-19.

Recognition and inhibition of SARS-CoV-2 by humoral innate immunity pattern recognition molecules.

The humoral arm of innate immunity includes diverse molecules with antibody-like functions, some of which serve as disease severity biomarkers in coronavirus disease 2019 (COVID-19). The present study was designed to conduct a systematic investigation of the interaction of human humoral fluid-phase pattern recognition molecules (PRMs) with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Of 12 PRMs tested, the long pentraxin 3 (PTX3) and mannose-binding lectin (MBL) bound the viral nucleocapsid and spike proteins, respectively. MBL bound trimeric spike protein, including that of variants of concern (VoC), in a glycan-dependent manner and inhibited SARS-CoV-2 in three in vitro models. Moreover, after binding to spike protein, MBL activated the lectin pathway of complement activation. Based on retention of glycosylation sites and modeling, MBL was predicted to recognize the Omicron VoC. Genetic polymorphisms at the MBL2 locus were associated with disease severity. These results suggest that selected humoral fluid-phase PRMs can play an important role in resistance to, and pathogenesis of, COVID-19, a finding with translational implications.

Macrophage expression and prognostic significance of the long pentraxin PTX3 in COVID-19.

Long pentraxin 3 (PTX3) is an essential component of humoral innate immunity, involved in resistance to selected pathogens and in the regulation of inflammation1-3. The present study was designed to assess the presence and significance of PTX3 in Coronavirus Disease 2019 (COVID-19)4-7. RNA-sequencing analysis of peripheral blood mononuclear cells, single-cell bioinformatics analysis and immunohistochemistry of lung autopsy samples revealed that myelomonocytic cells and endothelial cells express high levels of PTX3 in patients with COVID-19. Increased plasma concentrations of PTX3 were detected in 96 patients with COVID-19. PTX3 emerged as a strong independent predictor of 28-d mortality in multivariable analysis, better than conventional markers of inflammation, in hospitalized patients with COVID-19. The prognostic significance of PTX3 abundance for mortality was confirmed in a second independent cohort (54 patients). Thus, circulating and lung myelomonocytic cells and endothelial cells are a major source of PTX3, and PTX3 plasma concentration can serve as an independent strong prognostic indicator of short-term mortality in COVID-19.

An integrated view of humoral innate immunity: pentraxins as a paradigm.

The innate immune system consists of a cellular and a humoral arm. Pentraxins (e.g., the short pentraxin C reactive protein and the long pentraxin PTX3) are key components of the humoral arm of innate immunity which also includes complement components, collectins, and ficolins. In response to microorganisms and tissue damage, neutrophils, macrophages, and dendritic cells are major sources of fluid-phase pattern-recognition molecules (PRMs) belonging to different molecular classes. Humoral PRMs in turn interact with and regulate cellular effectors. Effector mechanisms of the humoral innate immune system include activation and regulation of the complement cascade; agglutination and neutralization; facilitation of recognition via cellular receptors (opsonization); and regulation of inflammation. Thus, the humoral arm of innate immunity is an integrated system consisting of different molecules and sharing functional outputs with antibodies.

IgG3 regulates tissue-like memory B cells in HIV-infected individuals.

Immunoglobulin G3 (IgG3) has an uncertain role in the response to infection with and vaccination against human immunodeficiency virus (HIV). Here we describe a regulatory role for IgG3 in dampening the immune system-activating effects of chronic HIV viremia on B cells. Secreted IgG3 was bound to IgM-expressing B cells in vivo in HIV-infected chronically viremic individuals but not in early-viremic or aviremic individuals. Tissue-like memory (TLM) B cells, a population expanded by persistent HIV viremia, bound large amounts of IgG3. IgG3 induced clustering of B cell antigen receptors (BCRs) on the IgM+ B cells, which was mediated by direct interactions between soluble IgG3 and membrane IgM of the BCR (IgM-BCR). The inhibitory IgG receptor CD32b (FcγRIIb), complement component C1q and inflammatory biomarker CRP contributed to the binding of secreted IgG3 onto IgM-expressing B cells of HIV-infected individuals. Notably, IgG3-bound TLM B cells were refractory to IgM-BCR stimulation, thus demonstrating that IgG3 can regulate B cells during chronic activation of the immune system.

PTX3 is an extrinsic oncosuppressor regulating complement-dependent inflammation in cancer.

PTX3 is an essential component of the humoral arm of innate immunity, playing a nonredundant role in resistance against selected microbes and in the regulation of inflammation. PTX3 activates and regulates the Complement cascade by interacting with C1q and with Factor H. PTX3 deficiency was associated with increased susceptibility to mesenchymal and epithelial carcinogenesis. Increased susceptibility of Ptx3(-/-) mice was associated with enhanced macrophage infiltration, cytokine production, angiogenesis, and Trp53 mutations. Correlative evidence, gene-targeted mice, and pharmacological blocking experiments indicated that PTX3 deficiency resulted in amplification of Complement activation, CCL2 production, and tumor-promoting macrophage recruitment. PTX3 expression was epigenetically regulated in selected human tumors (e.g., leiomyosarcomas and colorectal cancer) by methylation of the promoter region and of a putative enhancer. Thus, PTX3, an effector molecule belonging to the humoral arm of innate immunity, acts as an extrinsic oncosuppressor gene in mouse and man by regulating Complement-dependent, macrophage-sustained, tumor-promoting inflammation.

A model of human neural networks reveals NPTX2 pathology in ALS and FTLD.

Human cellular models of neurodegeneration require reproducibility and longevity, which is necessary for simulating age-dependent diseases. Such systems are particularly needed for TDP-43 proteinopathies1, which involve human-specific mechanisms2-5 that cannot be directly studied in animal models. Here, to explore the emergence and consequences of TDP-43 pathologies, we generated induced pluripotent stem cell-derived, colony morphology neural stem cells (iCoMoNSCs) via manual selection of neural precursors6. Single-cell transcriptomics and comparison to independent neural stem cells7 showed that iCoMoNSCs are uniquely homogenous and self-renewing. Differentiated iCoMoNSCs formed a self-organized multicellular system consisting of synaptically connected and electrophysiologically active neurons, which matured into long-lived functional networks (which we designate iNets). Neuronal and glial maturation in iNets was similar to that of cortical organoids8. Overexpression of wild-type TDP-43 in a minority of neurons within iNets led to progressive fragmentation and aggregation of the protein, resulting in a partial loss of function and neurotoxicity. Single-cell transcriptomics revealed a novel set of misregulated RNA targets in TDP-43-overexpressing neurons and in patients with TDP-43 proteinopathies exhibiting a loss of nuclear TDP-43. The strongest misregulated target encoded the synaptic protein NPTX2, the levels of which are controlled by TDP-43 binding on its 3' untranslated region. When NPTX2 was overexpressed in iNets, it exhibited neurotoxicity, whereas correcting NPTX2 misregulation partially rescued neurons from TDP-43-induced neurodegeneration. Notably, NPTX2 was consistently misaccumulated in neurons from patients with amyotrophic lateral sclerosis and frontotemporal lobar degeneration with TDP-43 pathology. Our work directly links TDP-43 misregulation and NPTX2 accumulation, thereby revealing a TDP-43-dependent pathway of neurotoxicity.

Higher-order structure and proteoforms of co-occurring C4b-binding protein assemblies in human serum.

The complement is a conserved cascade that plays a central role in the innate immune system. To maintain a delicate equilibrium preventing excessive complement activation, complement inhibitors are essential. One of the major fluid-phase complement inhibitors is C4b-binding protein (C4BP). Human C4BP is a macromolecular glycoprotein composed of two distinct subunits, C4BPα and C4BPß. These associate with vitamin K-dependent protein S (ProS) forming an ensemble of co-occurring higher-order structures. Here, we characterize these C4BP assemblies. We resolve and quantify isoforms of purified human serum C4BP using distinct single-particle detection techniques: charge detection mass spectrometry, and mass photometry accompanied by high-speed atomic force microscopy. Combining cross-linking mass spectrometry, glycoproteomics, and structural modeling, we report comprehensive glycoproteoform profiles and full-length structural models of the endogenous C4BP assemblies, expanding knowledge of this key complement inhibitor's structure and composition. Finally, we reveal that an increased C4BPα to C4BPß ratio coincides with elevated C-reactive protein levels in patient plasma samples. This observation highlights C4BP isoform variation and affirms a distinct role of co-occurring C4BP assemblies upon acute phase inflammation.

Childhood maltreatment influences adult brain structure through its effects on immune, metabolic, and psychosocial factors.

Childhood maltreatment (CM) leads to a lifelong susceptibility to mental ill-health which might be reflected by its effects on adult brain structure, perhaps indirectly mediated by its effects on adult metabolic, immune, and psychosocial systems. Indexing these systemic factors via body mass index (BMI), C-reactive protein (CRP), and rates of adult trauma (AT), respectively, we tested three hypotheses: (H1) CM has direct or indirect effects on adult trauma, BMI, and CRP; (H2) adult trauma, BMI, and CRP are all independently related to adult brain structure; and (H3) childhood maltreatment has indirect effects on adult brain structure mediated in parallel by BMI, CRP, and AT. Using path analysis and data from N = 116,887 participants in UK Biobank, we find that CM is related to greater BMI and AT levels, and that these two variables mediate CM's effects on CRP [H1]. Regression analyses on the UKB MRI subsample (N = 21,738) revealed that greater CRP and BMI were both independently related to a spatially convergent pattern of cortical effects (Spearman's ρ = 0.87) characterized by fronto-occipital increases and temporo-parietal reductions in thickness. Subcortically, BMI was associated with greater volume, AT with lower volume and CPR with effects in both directions [H2]. Finally, path models indicated that CM has indirect effects in a subset of brain regions mediated through its direct effects on BMI and AT and indirect effects on CRP [H3]. Results provide evidence that childhood maltreatment can influence brain structure decades after exposure by increasing individual risk toward adult trauma, obesity, and inflammation.

Sarilumab for Relapse of Polymyalgia Rheumatica during Glucocorticoid Taper.

BACKGROUND: More than half of patients with polymyalgia rheumatica have a relapse during tapering of glucocorticoid therapy. Previous studies have suggested that interleukin-6 blockade may be clinically useful in the treatment of polymyalgia rheumatica. Sarilumab, a human monoclonal antibody, binds interleukin-6 receptor α and efficiently blocks the interleukin-6 pathway. METHODS: In this phase 3 trial, we randomly assigned patients in a 1:1 ratio to receive 52 weeks of a twice-monthly subcutaneous injection of either sarilumab (at a dose of 200 mg) plus a 14-week prednisone taper or placebo plus a 52-week prednisone taper. The primary outcome at 52 weeks was sustained remission, which was defined as the resolution of signs and symptoms of polymyalgia rheumatica by week 12 and sustained normalization of the C-reactive protein level, absence of disease flare, and adherence to the prednisone taper from weeks 12 through 52. RESULTS: A total of 118 patients underwent randomization (60 to receive sarilumab and 58 to receive placebo). At week 52, sustained remission occurred in 28% (17 of 60 patients) in the sarilumab group and in 10% (6 of 58 patients) in the placebo group (difference, 18 percentage points; 95% confidence interval, 4 to 32; P = 0.02). The median cumulative glucocorticoid dose at 52 weeks was significantly lower in the sarilumab group than in the placebo group (777 mg vs. 2044 mg; P<0.001). The most common adverse events with sarilumab as compared with placebo were neutropenia (15% vs. 0%), arthralgia (15% vs. 5%), and diarrhea (12% vs. 2%). More treatment-related discontinuations were observed in the sarilumab group than in the placebo group (12% vs. 7%). CONCLUSIONS: Sarilumab showed significant efficacy in achieving sustained remission and reducing the cumulative glucocorticoid dose in patients with a relapse of polymyalgia rheumatica during glucocorticoid tapering. (Funded by Sanofi and Regeneron Pharmaceuticals; SAPHYR ClinicalTrials.gov number, NCT03600818.).

Characterization of the innate immune response to Streptococcus pneumoniae infection in zebrafish.

Streptococcus pneumoniae (pneumococcus) is one of the most frequent causes of pneumonia, sepsis and meningitis in humans, and an important cause of mortality among children and the elderly. We have previously reported the suitability of the zebrafish (Danio rerio) larval model for the study of the host-pathogen interactions in pneumococcal infection. In the present study, we characterized the zebrafish innate immune response to pneumococcus in detail through a whole-genome level transcriptome analysis and revealed a well-conserved response to this human pathogen in challenged larvae. In addition, to gain understanding of the genetic factors associated with the increased risk for severe pneumococcal infection in humans, we carried out a medium-scale forward genetic screen in zebrafish. In the screen, we identified a mutant fish line which showed compromised resistance to pneumococcus in the septic larval infection model. The transcriptome analysis of the mutant zebrafish larvae revealed deficient expression of a gene homologous for human C-reactive protein (CRP). Furthermore, knockout of one of the six zebrafish crp genes by CRISPR-Cas9 mutagenesis predisposed zebrafish larvae to a more severe pneumococcal infection, and the phenotype was further augmented by concomitant knockdown of a gene for another Crp isoform. This suggests a conserved function of C-reactive protein in anti-pneumococcal immunity in zebrafish. Altogether, this study highlights the similarity of the host response to pneumococcus in zebrafish and humans, gives evidence of the conserved role of C-reactive protein in the defense against pneumococcus, and suggests novel host genes associated with pneumococcal infection.

Inflammation and Cholesterol as Predictors of Cardiovascular Events Among 13 970 Contemporary High-Risk Patients With Statin Intolerance.

BACKGROUND: Among patients treated with statin therapy to guideline-recommended cholesterol levels, residual inflammatory risk assessed by high-sensitivity C-reactive protein (hsCRP) is at least as strong a predictor of future cardiovascular events as is residual risk assessed by low-density lipoprotein cholesterol (LDLC). Whether these relationships are present among statin-intolerant patients with higher LDLC levels is uncertain but has implications for the choice of preventive therapies, including bempedoic acid, an agent that reduces both LDLC and hsCRP. METHODS: The multinational CLEAR-Outcomes trial (Cholesterol Lowering via Bempedoic Acid, an ACL-Inhibiting Regimen Outcomes Trial) randomly allocated 13 970 statin-intolerant patients to 180 mg of oral bempedoic acid daily or matching placebo and followed them for a 4-component composite of incident myocardial infarction, stroke, coronary revascularization, or cardiovascular death, and for all-cause mortality. Quartiles of increasing baseline hsCRP and LDLC were assessed as predictors of future adverse events after adjustment for traditional risk factors and randomized treatment assignment. RESULTS: Compared with placebo, bempedoic acid reduced median hsCRP by 21.6% and mean LDLC levels by 21.1% at 6 months. Baseline hsCRP was significantly associated with the primary composite end point of major cardiovascular events (highest versus lowest hsCRP quartile; hazard ratio [HR], 1.43 [95% CI, 1.24-1.65]), cardiovascular mortality (HR, 2.00 [95% CI, 1.53-2.61]), and all-cause mortality (HR, 2.21 [95% CI, 1.79-2.73]). By contrast, the relationship of baseline LDLC quartile (highest versus lowest) to future events was smaller in magnitude for the primary composite cardiovascular end point (HR, 1.19 [95% CI, 1.04-1.37]) and neutral for cardiovascular mortality (HR, 0.90 [95% CI, 0.70-1.17]) and all-cause mortality (HR, 0.95 [95% CI, 0.78-1.16]). Risks were high for those with elevated hsCRP irrespective of LDLC level. Bempedoic acid demonstrated similar efficacy in reducing cardiovascular events across all levels of hsCRP and LDLC. CONCLUSIONS: Among contemporary statin-intolerant patients, inflammation assessed by hsCRP predicted risk for future cardiovascular events and death more strongly than hyperlipidemia assessed by LDLC. Compared with placebo, bempedoic acid had similar efficacy for reducing cardiovascular risk across hsCRP and LDLC strata. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02993406.

PTX3, a Humoral Pattern Recognition Molecule, in Innate Immunity, Tissue Repair, and Cancer.

Innate immunity includes a cellular and a humoral arm. PTX3 is a fluid-phase pattern recognition molecule conserved in evolution which acts as a key component of humoral innate immunity in infections of fungal, bacterial, and viral origin. PTX3 binds conserved microbial structures and self-components under conditions of inflammation and activates effector functions (complement, phagocytosis). Moreover, it has a complex regulatory role in inflammation, such as ischemia/reperfusion injury and cancer-related inflammation, as well as in extracellular matrix organization and remodeling, with profound implications in physiology and pathology. Finally, PTX3 acts as an extrinsic oncosuppressor gene by taming tumor-promoting inflammation in murine and selected human tumors. Thus evidence suggests that PTX3 is a key homeostatic component at the crossroad of innate immunity, inflammation, tissue repair, and cancer. Dissecting the complexity of PTX3 pathophysiology and human genetics paves the way to diagnostic and therapeutic exploitation.

Monitoring synaptic pathology in Alzheimer's disease through fluid and PET imaging biomarkers: a comprehensive review and future perspectives.

Alzheimer's disease (AD) is currently constrained by limited clinical treatment options. The initial pathophysiological event, which can be traced back to decades before the clinical symptoms become apparent, involves the excessive accumulation of amyloid-beta (Aß), a peptide comprised of 40-42 amino acids, in extraneuronal plaques within the brain. Biochemical and histological studies have shown that overaccumulation of Aß instigates an aberrant escalation in the phosphorylation and secretion of tau, a microtubule-binding axonal protein. The accumulation of hyperphosphorylated tau into intraneuronal neurofibrillary tangles is in turn correlated with microglial dysfunction and reactive astrocytosis, culminating in synaptic dysfunction and neurodegeneration. As neurodegeneration progresses, it gives rise to mild clinical symptoms of AD, which may eventually evolve into overt dementia. Synaptic loss in AD may develop even before tau alteration and in response to possible elevations in soluble oligomeric forms of Aß associated with early AD. These findings largely rely on post-mortem autopsy examinations, which typically involve a limited number of patients. Over the past decade, a range of fluid biomarkers such as neurogranin, α-synuclein, visinin-like protein 1 (VILIP-1), neuronal pentraxin 2, and ß-synuclein, along with positron emission tomography (PET) markers like synaptic vesicle glycoprotein 2A, have been developed. These advancements have facilitated the exploration of how synaptic markers in AD patients correlate with cognitive impairment. However, fluid biomarkers indicating synaptic loss have only been validated in cerebrospinal fluid (CSF), not in plasma, with the exception of VILIP-1. The most promising PET radiotracer, [11C]UCB-J, currently faces significant challenges hindering its widespread clinical use, primarily due to the necessity of a cyclotron. As such, additional research geared toward the exploration of synaptic pathology biomarkers is crucial. This will not only enable their extensive clinical application, but also refine the optimization process of AD pharmacological trials.

Diagnostic and Prognostic Value of Peripheral Neutrophil CD64 Index in Elderly Patients with Community-Acquired Pneumonia.

Community-acquired pneumonia (CAP) is a leading cause of hospitalization and mortality in the elderly. The peripheral blood neutrophil CD64 (nCD64) index is increasingly recognized for its association with poor pneumonia prognosis. A comprehensive investigation involving 128 elderly patients diagnosed with CAP, including 96 with non-severe CAP and 32 with severe CAP, from January 2020 to January 2021 was performed. The nCD64 index, CD4+, CD8+, C-reactive protein (CRP), white blood cell (WBC) count, procalcitonin (PCT), neutrophil (NEUT), and B lymphocyte count were determined using flow cytometry. Our findings reveal that patients with severe CAP exhibited significantly higher levels of nCD64 index, NEUT, WBC, CRP, and PCT. Intriguingly, lower CRP, nCD64 index, CURB-65 score, and PCT were associated with a higher survival rate. Notably, the nCD64 index demonstrated remarkable predictive efficiency for 28-d survival in CAP patients [area under the curve (AUC) = 0.907], surpassing other markers and even showing enhanced predictive power when combined with the CURB-65 score (AUC = 0.905). Furthermore, a negative association was observed between the nCD64 index and both CD4+, CD4+/CD8+ ratios, and B lymphocytes, highlighting its potential role in immune dysregulation. These findings underscore the critical importance of the nCD64 index in the early diagnosis, risk stratification, and prognostic evaluation of infections and immune responses in elderly CAP patients.

C-Reactive Protein: The Most Familiar Stranger.

C-reactive protein (CRP) is a highly conserved pentraxin with pattern recognition receptor-like activities. However, despite being used widely as a clinical marker of inflammation, the in vivo functions of CRP and its roles in health and disease remain largely unestablished. This is, to certain extent, due to the drastically different expression patterns of CRP in mice and rats, raising concerns about whether the functions of CRP are essential and conserved across species and how these model animals should be manipulated to examine the in vivo actions of human CRP. In this review, we discuss recent advances highlighting the essential and conserved functions of CRP across species, and propose that appropriately designed animal models can be used to understand the origin-, conformation-, and localization-dependent actions of human CRP in vivo. The improved model design will contribute to establishing the pathophysiological roles of CRP and facilitate the development of novel CRP-targeting strategies.

Innate Immune Zonation in the Liver: NF-κB (p50) Activation and C-Reactive Protein Expression in Response to Endotoxemia Are Zone Specific.

Hepatic innate immune function plays an important role in the pathogenesis of many diseases. Importantly, a growing body of literature has firmly established the spatial heterogeneity of hepatocyte metabolic function; however, whether innate immune function is zonated remains unknown. To test this question, we exposed adult C57BL/6 mice to endotoxemia, and hepatic tissue was assessed for the acute phase response (APR). The zone-specific APR was evaluated in periportal and pericentral/centrilobular hepatocytes isolated using digitonin perfusion and on hepatic tissue using RNAscope and immunohistochemistry. Western blot, EMSA, chromatin immunoprecipitation, and immunohistochemistry were used to determine the role of the transcription factor NF-κB in mediating hepatic C-reactive protein (CRP) expression. Finally, the ability of mice lacking the NF-κB subunit p50 (p50-/-) to raise a hepatic APR was evaluated. We found that endotoxemia induces a hepatocyte transcriptional APR in both male and female mice, with Crp, Apcs, Fga, Hp, and Lbp expression being enriched in pericentral/centrilobular hepatocytes. Focusing our work on CRP expression, we determined that NF-κB transcription factor subunit p50 binds to consensus sequence elements present in the murine CRP promoter. Furthermore, pericentral/centrilobular hepatocyte p50 nuclear translocation is temporally associated with zone-specific APR during endotoxemia. Lastly, the APR and CRP expression is blunted in endotoxemic p50-/- mice. These results demonstrate that the murine hepatocyte innate immune response to endotoxemia includes zone-specific activation of transcription factors and target gene expression. These results support further study of zone-specific hepatocyte innate immunity and its role in the development of various disease states.

Vortioxetine for the treatment of post-COVID-19 condition: a randomized controlled trial.

Hitherto no therapeutic has received regulatory approval for the treatment of post-COVID-19 condition (PCC). Cognitive deficits, mood symptoms and significant reduction in health-related quality of life (HRQoL) are highly replicated and debilitating aspects of PCC. We sought to determine the impact of vortioxetine on the foregoing symptoms and HRQoL in persons living with PCC. An 8-week randomized, double-blind, placebo-controlled study of adults ≥ 18 years of age residing in Canada and who are experiencing symptoms of World Health Organization (WHO)-defined PCC, with a history of confirmed SARS-CoV-2 infection, was conducted. Recruitment began November 2021 and ended January 2023. Of the 200 participants enrolled (487 invited: 121 ineligible and 59 eligible but declined participation; 307 cleared pre-screening stage), a total of 149 participants were randomized (1:1) to receive either vortioxetine (5-20 mg, n = 75) or placebo (n = 74) daily for 8 weeks of double-blind treatment (i.e. end point). The primary outcome was the change from baseline-to-end point in the Digit Symbol Substitution Test. Secondary outcomes included the effect on depressive symptoms and HRQoL, as measured by changes from baseline-to-end point on the Quick Inventory of Depressive Symptomatology 16-item and WHO Wellbeing Scale 5-item, respectively. A total of 68 (90.7%) participants randomized to vortioxetine and 73 (98.6%) participants randomized to placebo completed all 8 weeks. Between-group analysis did not show a significant difference in the overall change in cognitive function [P = 0.361, 95% confidence interval (CI) (-0.179, 0.492)]. However, in the fully adjusted model, a significant treatment × time interaction was observed in favour of vortioxetine treatment with baseline c-reactive protein (CRP) as a moderator (P = 0.012). In addition, a significant improvement in Digit Symbol Substitution Test scores were observed in vortioxetine versus placebo treated participants in those whose baseline CRP was above the mean (P = 0.045). Moreover, significant improvement was obtained in measures of depressive symptoms [P < 0.001, 95% CI (-4.378, -2.323)] and HRQoL [P < 0.001, 95% CI (2.297, 4.647)] in vortioxetine-treated participants and between the treatment groups [depressive symptoms: P = 0.026, 95% CI (-2.847, -0.185); HRQoL: P = 0.004, 95% CI (0.774, 3.938)]. Although vortioxetine did not improve cognitive function in the unadjusted model, when adjusting for CRP, a significant pro-cognitive effect was observed; antidepressant effects and improvement in HRQoL in this debilitating disorder were also noted.

PTX3 structure determination using a hybrid cryoelectron microscopy and AlphaFold approach offers insights into ligand binding and complement activation.

Pattern recognition molecules (PRMs) form an important part of innate immunity, where they facilitate the response to infections and damage by triggering processes such as inflammation. The pentraxin family of soluble PRMs comprises long and short pentraxins, with the former containing unique N-terminal regions unrelated to other proteins or each other. No complete high-resolution structural information exists about long pentraxins, unlike the short pentraxins, where there is an abundance of both X-ray and cryoelectron microscopy (cryo-EM)-derived structures. This study presents a high-resolution structure of the prototypical long pentraxin, PTX3. Cryo-EM yielded a 2.5-Å map of the C-terminal pentraxin domains that revealed a radically different quaternary structure compared to other pentraxins, comprising a glycosylated D4 symmetrical octameric complex stabilized by an extensive disulfide network. The cryo-EM map indicated α-helices that extended N terminal of the pentraxin domains that were not fully resolved. AlphaFold was used to predict the remaining N-terminal structure of the octameric PTX3 complex, revealing two long tetrameric coiled coils with two hinge regions, which was validated using classification of cryo-EM two-dimensional averages. The resulting hybrid cryo-EM/AlphaFold structure allowed mapping of ligand binding sites, such as C1q and fibroblast growth factor-2, as well as rationalization of previous biochemical data. Given the relevance of PTX3 in conditions ranging from COVID-19 prognosis, cancer progression, and female infertility, this structure could be used to inform the understanding and rational design of therapies for these disorders and processes.

Pharmacologic modulation of intracellular Na+ concentration with ranolazine impacts inflammatory response in humans and mice.

Changes in Ca2+ influx during proinflammatory stimulation modulates cellular responses, including the subsequent activation of inflammation. Whereas the involvement of Ca2+ has been widely acknowledged, little is known about the role of Na+. Ranolazine, a piperazine derivative and established antianginal drug, is known to reduce intracellular Na+ as well as Ca2+ levels. In stable coronary artery disease patients (n = 51) we observed reduced levels of high-sensitive C-reactive protein (CRP) 3 mo after the start of ranolazine treatment (n = 25) as compared to the control group. Furthermore, we found that in 3,808 acute coronary syndrome patients of the MERLIN-TIMI 36 trial, individuals treated with ranolazine (1,934 patients) showed reduced CRP values compared to placebo-treated patients. The antiinflammatory effects of sodium modulation were further confirmed in an atherosclerotic mouse model. LDL-/- mice on a high-fat diet were treated with ranolazine, resulting in a reduced atherosclerotic plaque burden, increased plaque stability, and reduced activation of the immune system. Pharmacological Na+ inhibition by ranolazine led to reduced express of adhesion molecules and proinflammatory cytokines and reduced adhesion of leukocytes to activated endothelium both in vitro and in vivo. We demonstrate that functional Na+ shuttling is required for a full cellular response to inflammation and that inhibition of Na+ influx results in an attenuated inflammatory reaction. In conclusion, we demonstrate that inhibition of Na+-Ca2+ exchange during inflammation reduces the inflammatory response in human endothelial cells in vitro, in a mouse atherosclerotic disease model, and in human patients.