Systemic Inflammation and Microbial Translocation Are Characteristic Features of SARS-CoV-2-Related Multisystem Inflammatory Syndrome in Children

BACKGROUND: Multisystem inflammatory syndrome in children (MIS-C) is a rare manifestation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children that can result in increased morbidity and mortality. The inflammatory underpinnings of MIS-C have not been examined in detail. METHODS: We examined the plasma levels of acute phase proteins and microbial translocation markers in children with MIS-C, children with acute coronavirus disease 2019 (COVID-19) infection, SARS-CoV-2-seropositive children, and controls. RESULTS: MIS-C children exhibited significantly higher levels of C-reactive protein (CRP), alpha2 macroglobulin (α2M), serum amyloid P (SAP), lipopolysaccharide (LPS), sCD14, and LPS binding protein (LBP) and significantly lower levels of haptoglobin (Hp) in comparison with seropositive, control, and/or COVID-19 children. In addition, COVID-19 children exhibited significantly higher levels of most of the above markers in comparison with seropositive and control children. Principal component analysis using a set of these markers could clearly discriminate MIS-C and COVID-19 from seropositive and control children. MIS-C children requiring pediatric intensive care unit admission and COVID-19 children with severe disease had higher levels of CRP, SAP, and/or sCD14 at admission. CONCLUSIONS: Our study describes the role of systemic inflammation and microbial translocation markers in children with MIS-C and COVID-19 and therefore helps in advancing our understanding of the pathogenesis of different presentations of SARS-CoV-2 infection in children

Role of matrix metalloproteinases in multi-system inflammatory syndrome and acute COVID-19 in children

INTRODUCTION: Multisystem Inflammatory Syndrome in children (MIS-C) is a serious inflammatory sequela of SARS-CoV2 infection. The pathogenesis of MIS-C is vague and matrix metalloproteinases (MMPs) may have an important role. Matrix metalloproteinases (MMPs) are known drivers of lung pathology in many diseases. METHODS: To elucidate the role of MMPs in pathogenesis of pediatric COVID-19, we examined their plasma levels in MIS-C and acute COVID-19 children and compared them to convalescent COVID-19 and children with other common tropical diseases (with overlapping clinical manifestations). RESULTS: Children with MIS-C had elevated levels of MMPs (P < 0.005 statistically significant) in comparison to acute COVID-19, other tropical diseases (Dengue fever, typhoid fever, and scrub typhus fever) and convalescent COVID-19 children. PCA and ROC analysis (sensitivity 84–100% and specificity 80–100%) showed that MMP-8, 12, 13 could help distinguish MIS-C from acute COVID-19 and other tropical diseases with high sensitivity and specificity. Among MIS-C children, elevated levels of MMPs were seen in children requiring intensive care unit admission as compared to children not needing intensive care. Similar findings were noted when children with severe/moderate COVID-19 were compared to children with mild COVID-19. Finally, MMP levels exhibited significant correlation with laboratory parameters, including lymphocyte counts, CRP, D-dimer, Ferritin and Sodium levels. DISCUSSION: Our findings suggest that MMPs play a pivotal role in the pathogenesis of MIS-C and COVID-19 in children and may help distinguish MIS-C from other conditions with overlapping clinical presentation

Unique cellular immune signatures of multisystem inflammatory syndrome in children

The clinical presentation of MIS-C overlaps with other infectious/non-infectious diseases such as acute COVID-19, Kawasaki disease, acute dengue, enteric fever, and systemic lupus erythematosus. We examined the ex-vivo cellular parameters with the aim of distinguishing MIS-C from other syndromes with overlapping clinical presentations. MIS-C children differed from children with non-MIS-C conditions by having increased numbers of naïve CD8(+) T cells, naïve, immature and atypical memory B cells and diminished numbers of transitional memory, stem cell memory, central and effector memory CD4(+) and CD8(+) T cells, classical, activated memory B and plasma cells and monocyte (intermediate and non-classical) and dendritic cell (plasmacytoid and myeloid) subsets. All of the above alterations were significantly reversed at 6–9 months post-recovery in MIS-C. Thus, MIS-C is characterized by a distinct cellular signature that distinguishes it from other syndromes with overlapping clinical presentations. Trial Registration: ClinicalTrials.gov clinicaltrial.gov. No: NCT04844242

Analyzing the flash crossdomain policies

Adobe Flash is a multimedia platform used for developing rich internet applications. Flash also facilitates sharing resources and data between flash files on different domains. Sites that allow sharing of content need to host a crossdomain policy file, crossdomain.xml which has a list of websites that can access resources from this site. This thesis attempts to survey the crossdomain.xml Flash policy file present accross the Alexa top 50,000 websites. We found that 3609 out of the 47197 surveyed sites had unrestricted crossdomain Flash access. These numbers suggest that Flash crossdomain.xml policy files are liable to misconfiguration. We also propose some mitigation techniques for the sam

Analyzing the flash crossdomain policies

Adobe Flash is a multimedia platform used for developing rich internet applications. Flash also facilitates sharing resources and data between flash files on different domains. Sites that allow sharing of content need to host a crossdomain policy file, crossdomain.xml which has a list of websites that can access resources from this site. This thesis attempts to survey the crossdomain.xml Flash policy file present accross the Alexa top 50,000 websites. We found that 3609 out of the 47197 surveyed sites had unrestricted crossdomain Flash access. These numbers suggest that Flash crossdomain.xml policy files are liable to misconfiguration. We also propose some mitigation techniques for the sam

Delineating the impact of pathogenic mutations on the conformational dynamics of HDL’s vital protein ApoA1: a combined computational and molecular dynamic simulation approach

Apolipoprotein A1 (ApoA1), is the important component of high‐density lipoproteins (HDL), that has key role in HDL biogenesis, cholesterol trafficking, and reverse cholesterol transport (RCT). Non-synonymous Single Nucleotide Polymorphisms (nsSNPs) in ApoA1 have been linked to cardiovascular diseases and amyloidosis as they alter the protein’s native structure and function. Therefore in this study, we attempted to understand the molecular pathogenicity profile of nsSNPs of ApoA1 using various computational approaches. We used state-of-the-art computational methods to thoroughly investigate the 295 ApoA1 nsSNPs at sequence and structural levels. Seven nsSNPs (L13R, L84R, L84P, L99P, R173P, L187P, and L238P) out of 295 were classified as the most deleterious and destabilizing. In order to estimate the effect of such destabilizing mutations on the protein conformation, all-atom molecular dynamics simulations (MDS) of ApoA1 wild-type (WT), L99P and R173P for 100 ns, was carried out using GROMACS 5.0.1 package. The MD simulation investigation revealed significant structural alterations in L99P and R173P. In addition, they had changed principal component analysis and electrostatic surface potential, decreased structural compactness, and intramolecular hydrogen bonds, which supported the rationale underpinning ApoA1 dysfunction with such mutations. This work sheds light on ApoA1 dysfunction due to single amino acid alterations, and offers new insight into the molecular basis of ApoA1-related diseases progression. Communicated by Ramaswamy H. Sarma ApoA1 is a key HDL protein involved in RCT and HDL synthesis. Mutations in the ApoA1 protein can lead to defects in RCT and HDL biogenesis. In total 295nsSNPS of ApoA1 protein were studied using various computational approaches. Seven highly pathogenic and destabilizing mutations were found (L13R, L84R, L84P, L99P, R173P, L187P, and L238P). Further MD results showed L99P and R173P mutations in ApoA1 are highly destabilizing.</p

Elucidating systemic immune responses to acute and convalescent SARS‐CoV‐2 infection in children and elderly individuals

Abstract Background Severe Acute Respiratory Syndrome Coronavirus‐2 (SARS‐CoV‐2), a causative pathogen of the COVID‐19 pandemic, affects all age groups. However, various studies have shown that COVID‐19 presentation and severity vary considerably with age. We, therefore, wanted to examine the differences between the immune responses of children with COVID‐19 and elderly COVID‐19 individuals. Methods We analyzed cytokines, chemokines, growth factors, and acute phase proteins in acute and convalescent COVID‐19 children and the elderly with acute and convalescent COVID‐19. Results We show that most of the pro‐inflammatory cytokines (interferon [IFN]γ, interleukin [IL]‐2, tumor necrosis factor‐α [TNFα], IL‐1α, IFNα, IFNβ, IL‐6, IL‐12, IL‐3, IL‐7, IL‐1Ra, IL‐13, and IL‐10), chemokines (CCL4, CCL11, CCL19, CXCL1, CXCL2, CXCL8, and CXL10), growth factors (vascular endothelial growth factor and CD40L) and acute phase proteins (C‐reactive protein, serum amyloid P, and haptoglobin) were decreased in children with acute COVID 19 as compared with elderly individuals. In contrast, children with acute COVID‐19 exhibited elevated levels of cytokines‐ IL‐1β, IL‐33, IL‐4, IL‐5, and IL‐25, growth factors—fibroblast growth factor‐2, platelet‐ derived growth factors‐BB, and transforming growth factorα as compared with elderly individuals. Similar, differences were manifest in children and elderly with convalescent COVID‐19. Conclusion Thus, COVID‐19 children are characterized by distinct cytokine/chemokine/growth factor/acute phase protein markers that are markedly different from elderly COVID‐19 individuals

Alterations of adipokines, pancreatic hormones and incretins in acute and convalescent COVID-19 children

Abstract Background The Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), accountable for Coronavirus disease 2019 (COVID-19), may cause hyperglycemia and additional systemic complexity in metabolic parameters. It is unsure even if the virus itself causes type 1 or type 2 diabetes mellitus (T1DM or T2DM). Furthermore, it is still unclear whether even recuperating COVID-19 individuals have an increased chance to develop new-onset diabetes. Methods We wanted to determine the impact of COVID-19 on the levels of adipokines, pancreatic hormones, incretins and cytokines in acute COVID-19, convalescent COVID-19 and control children through an observational study. We performed a multiplex immune assay analysis and compared the plasma levels of adipocytokines, pancreatic hormones, incretins and cytokines of children presenting with acute COVID-19 infection and convalescent COVID-19. Results Acute COVID-19 children had significantly elevated levels of adipsin, leptin, insulin, C-peptide, glucagon and ghrelin in comparison to convalescent COVID-19 and controls. Similarly, convalescent COVID-19 children had elevated levels of adipsin, leptin, insulin, C-peptide, glucagon, ghrelin and Glucagon-like peptide-1 (GLP-1) in comparison to control children. On the other hand, acute COVID-19 children had significantly decreased levels of adiponectin and Gastric Inhibitory Peptide (GIP) in comparison to convalescent COVID-19 and controls. Similarly, convalescent COVID-19 children had decreased levels of adiponectin and GIP in comparison to control children. Acute COVID-19 children had significantly elevated levels of cytokines, (Interferon (IFN)) IFNγ, Interleukins (IL)-2, TNFα, IL-1α, IL-1β, IFNα, IFNβ, IL-6, IL-12, IL-17A and Granulocyte-Colony Stimulating Factors (G-CSF) in comparison to convalescent COVID-19 and controls. Convalescent COVID-19 children had elevated levels of IFNγ, IL-2, TNFα, IL-1α, IL-1β, IFNα, IFNβ, IL-6, IL-12, IL-17A and G-CSF in comparison to control children. Additionally, Principal component Analysis (PCA) analysis distinguishes acute COVID-19 from convalescent COVID-19 and controls. The adipokines exhibited a significant correlation with the levels of pro-inflammatory cytokines. Conclusion Children with acute COVID-19 show significant glycometabolic impairment and exaggerated cytokine responses, which is different from convalescent COVID-19 infection and controls