Human inherited complete STAT2 deficiency underlies inflammatory viral diseases.

STAT2 is a transcription factor activated by type I and III IFNs. We report 23 patients with loss-of-function variants causing autosomal recessive (AR) complete STAT2 deficiency. Both cells transfected with mutant STAT2 alleles and the patients' cells displayed impaired expression of IFN-stimulated genes and impaired control of in vitro viral infections. Clinical manifestations from early childhood onward included severe adverse reaction to live attenuated viral vaccines (LAV) and severe viral infections, particularly critical influenza pneumonia, critical COVID-19 pneumonia, and herpes simplex virus type 1 (HSV-1) encephalitis. The patients displayed various types of hyperinflammation, often triggered by viral infection or after LAV administration, which probably attested to unresolved viral infection in the absence of STAT2-dependent types I and III IFN immunity. Transcriptomic analysis revealed that circulating monocytes, neutrophils, and CD8+ memory T cells contributed to this inflammation. Several patients died from viral infection or heart failure during a febrile illness with no identified etiology. Notably, the highest mortality occurred during early childhood. These findings show that AR complete STAT2 deficiency underlay severe viral diseases and substantially impacts survival.

The brain reacting to COVID-19: analysis of the cerebrospinal fluid proteome, RNA and inflammation.

Patients with COVID-19 can have a variety of neurological symptoms, but the active involvement of central nervous system (CNS) in COVID-19 remains unclear. While routine cerebrospinal fluid (CSF) analyses in patients with neurological manifestations of COVID-19 generally show no or only mild inflammation, more detailed data on inflammatory mediators in the CSF of patients with COVID-19 are scarce. We studied the inflammatory response in paired CSF and serum samples of patients with COVID-19 (n = 38). Patients with herpes simplex virus encephalitis (HSVE, n = 10) and patients with non-inflammatory, non-neurodegenerative neurological diseases (n = 28) served as controls. We used proteomics, enzyme-linked immunoassays, and semiquantitative cytokine arrays to characterize inflammatory proteins. Autoantibody screening was performed with cell-based assays and native tissue staining. RNA sequencing of long-non-coding RNA and circular RNA was done to study the transcriptome. Proteomics on single protein level and subsequent pathway analysis showed similar yet strongly attenuated inflammatory changes in the CSF of COVID-19 patients compared to HSVE patients with, e.g., downregulation of the apolipoproteins and extracellular matrix proteins. Protein upregulation of the complement system, the serpin proteins pathways, and other proteins including glycoproteins alpha-2 and alpha-1 acid. Importantly, calculation of interleukin-6, interleukin-16, and CXCL10 CSF/serum indices suggest that these inflammatory mediators reach the CSF from the systemic circulation, rather than being produced within the CNS. Antibody screening revealed no pathological levels of known neuronal autoantibodies. When stratifying COVID-19 patients into those with and without bacterial superinfection as indicated by elevated procalcitonin levels, inflammatory markers were significantly (p < 0.01) higher in those with bacterial superinfection. RNA sequencing in the CSF revealed 101 linear RNAs comprising messenger RNAs, and two circRNAs being significantly differentially expressed in COVID-19 than in non-neuroinflammatory controls and neurodegenerative patients. Our findings may explain the absence of signs of intrathecal inflammation upon routine CSF testing despite the presence of SARS-CoV2 infection-associated neurological symptoms. The relevance of blood-derived mediators of inflammation in the CSF for neurological COVID-19 and post-COVID-19 symptoms deserves further investigation.

Oral manifestations of COVID-19 correlated to medical and drug history, a survey on infected medical doctors. (preprint)

Objective Reporting the oral symptoms of COVID-19 and correlate the occurrence of these symptoms with various possible etiologic factors. Methods A cross-sectional web-based survey targeted Medical doctors infected with COVID-19. The survey questioned the diagnosis of the disease, the severity of the disease symptoms, the oral symptoms along with drug and medical history. A total sample of 312 response were analyzed and correlated with various factors including the patients’ age, sex, medical history, drug history, hospitalization and severity of COVID-19 symptoms. Results Oral manifestations were reported in 72.5% of the participants. The most common oral manifestations were dysgeusia in 76% of patients which was partial in 64% of the participants. Xerostomia was reported in 41.6% of cases. Aphthous stomatitis and recurrent herpetic infections were also reported. The occurrence of oral symptoms was increased among population with previous medical history with no evidence of correlation with any other factors regarding gender, certain medications or oral hygiene. Conclusion The most common oral manifestations of COVID-19 are dysgeusia and xerostomia and the occurrence of oral manifestations is increased in patients with previous medical condition. Clinical relevance: awareness of the possible symptoms and medical conditions that may potentiate the severity of oral symptoms during COVID-19 infection allows targeting the precise mechanism to treat the oral symptoms.

TONSILS ARE MAJOR SITES OF PROLONGED SARS-COV-2 INFECTION IN CHILDREN (preprint)

In the present study, we show that SARS-CoV-2 can infect palatine tonsils and adenoids in children without symptoms of COVID-19, with no history of recent upper airway infection. We studied 48 children undergoing tonsillectomy due to snoring/OSA or recurrent tonsillitis between October 2020 and September 2021. Briefly, nasal cytobrush (NC), nasal wash (NW) and tonsillar tissue fragments obtained at surgery were tested by RT-PCR, immunohistochemistry (IHC), flow cytometry and neutralization assay. We detected the presence of SARS-CoV-2 in at least one specimen tested in 25% of patients (20% in palatine tonsils and 16.27% in adenoids, 10.41% of NC and 6.25% of NW). Importantly, in 2 of the children there was evidence of laboratory-confirmed acute infection 2 and 5 months before surgery. IHC revealed the presence of SARS-CoV-2 nucleoprotein in epithelial surface and in lymphoid cells in both extrafollicular and follicular regions, in adenoids and palatine tonsils. Flow cytometry showed that CD20+ B lymphocytes were the most infected phenotypes by SARS-CoV-2 NP, followed by CD4+ and CD8+ T lymphocytes, and CD14+ macrophages and dendritic cells. Additionally, IF indicated that SARS-CoV-2-infected tonsillar tissues had increased expression of ACE2 and TMPRSS2. NGS sequencing demonstrated the presence of different SARS CoV-2 variants in tonsils from different tissues. SARS-CoV-2 antigen detection was not restricted to tonsils, but was also detected in nasal cells from the olfactory region. In conclusion, palatine tonsils and adenoids are sites of prolonged infection by SARS-CoV-2 in children, even without COVID-19 symptoms.

TRIM18 is a critical regulator of viral myocarditis and organ inflammation.

BACKGROUND: Infections by viruses including severe acute respiratory syndrome coronavirus 2 could cause organ inflammations such as myocarditis, pneumonia and encephalitis. Innate immunity to viral nucleic acids mediates antiviral immunity as well as inflammatory organ injury. However, the innate immune mechanisms that control viral induced organ inflammations are unclear. METHODS: To understand the role of the E3 ligase TRIM18 in controlling viral myocarditis and organ inflammation, wild-type and Trim18 knockout mice were infected with coxsackievirus B3 for inducing viral myocarditis, influenza A virus PR8 strain and human adenovirus for inducing viral pneumonia, and herpes simplex virus type I for inducing herpes simplex encephalitis. Mice survivals were monitored, and heart, lung and brain were harvested for histology and immunohistochemistry analysis. Real-time PCR, co-immunoprecipitation, immunoblot, enzyme-linked immunosorbent assay, luciferase assay, flow cytometry, over-expression and knockdown techniques were used to understand the molecular mechanisms of TRIM18 in regulating type I interferon (IFN) production after virus infection in this study. RESULTS: We find that knockdown or deletion of TRIM18 in human or mouse macrophages enhances production of type I IFN in response to double strand (ds) RNA and dsDNA or RNA and DNA virus infection. Importantly, deletion of TRIM18 protects mice from viral myocarditis, viral pneumonia, and herpes simplex encephalitis due to enhanced type I IFN production in vivo. Mechanistically, we show that TRIM18 recruits protein phosphatase 1A (PPM1A) to dephosphorylate TANK binding kinase 1 (TBK1), which inactivates TBK1 to block TBK1 from interacting with its upstream adaptors, mitochondrial antiviral signaling (MAVS) and stimulator of interferon genes (STING), thereby dampening antiviral signaling during viral infections. Moreover, TRIM18 stabilizes PPM1A by inducing K63-linked ubiquitination of PPM1A. CONCLUSIONS: Our results indicate that TRIM18 serves as a negative regulator of viral myocarditis, lung inflammation and brain damage by downregulating innate immune activation induced by both RNA and DNA viruses. Our data reveal that TRIM18 is a critical regulator of innate immunity in viral induced diseases, thereby identifying a potential therapeutic target for treatment.

Herpesviral encephalitis associated with bortezomib use in a patient with multiple myeloma and associated light-chain amyloidosis.

INTRODUCTION: Bortezomib is proteasome inhibitor used in multiple myeloma treatment. The reactivation of herpes simplex virus (HSV) and varicella-zoster virus (VZV) during bortezomib-based therapy is a well-known adverse event. Antiviral prophylaxis is mandatory. Nevertheless, reports of herpesviral encephalitis are scarce. CASE REPORT: A 57-year-old multiple myeloma patient who during CyBorD protocol (Bortezomib, cyclophosphamide, and dexamethasone), after a transient suspension of antiviral prophylaxis presented progressive headaches unresponsive to conventional analgesics, asthenia, fever, episodic visual hallucinations, and vesicular lesions in the right supraorbital and frontal region. Herpetic encephalitis was diagnosed after detecting herpes zoster in cerebrospinal fluid. MANAGEMENT & OUTCOME: The patient was treated with acyclovir 500mg every 6 hours for 21 days, and subsequent valacyclovir prophylaxis achieving an excellent clinical evolution. Anti-myeloma treatment was changed to lenalidomide and dexamethasone achieving a durable complete response. Herpesviral encephalitis is a rare but severe complication associated with the use of Bortezomib, especially when patients did not receive acyclovir prophylaxis. However, a rapid detection based on the clinical suspicion, and the prompt start of treatment, may lead to overcome this adverse event.

SARS-CoV-2-associated haemorrhagic encephalitis mimicking Herpes encephalitis.

Although acute encephalopathy is quite commonly seen in patients of SARS-CoV-2 infection, encephalitis characterised by brain inflammation is relatively rare. Encephalitis caused by Herpes simplex type 1 is the most common cause of identified sporadic encephalitis, and early diagnosis and prompt treatment can prevent the devastating outcome. In this brief communication, we report a case of SARS-CoV-2 associated haemorrhagic encephalitis mimicking herpes encephalitis. In today's pandemic era, it is especially important to distinguish herpes encephalitis from SARS-CoV-2-associated encephalitis as treatment and prognosis of both the conditions differ greatly. This case highlights the importance of suspecting SARS-CoV-2 infection in a patient presenting with clinical symptoms and brain imaging suggestive of Herpes encephalitis.

Herpes simplex encephalitis following ChAdOx1 nCoV-19 vaccination: a case report and review of the literature.

BACKGROUND: Ever since the administration of early doses of COVID-19 vaccines, instances of adverse effects have been reported. Viral infections, specifically herpes simplex reinfection and coinfections, have been reported following administration of different types of vaccines. To our knowledge, there have not been any reports of herpes simplex encephalitis following administration of any type of COVID-19 vaccine to date. CASE PRESENTATION: In this article intends to report a case of herpes simplex encephalitis in a 27-year-old male patient who was vaccinated with the ChAdOx1 nCoV-19 vaccine. CONCLUSIONS: Our study suggests a possible but very rare side effect of ChAdOx1 nCoV-19 vaccine, which requires immediate medical attention and can lead to devastating consequences if left undiagnosed and untreated.

The Brain Reacting to COVID-19: Analysis of the Cerebrospinal Fluid and Serum Proteome, Transcriptome and Inflammatory Proteins (preprint)

Patients with COVID-19 can have a variety of neurological symptoms, but the pathomechanism of CNS involvement in COVD-19 remains unclear. While routine cerebrospinal fluid (CSF) analyses in patients with neurological manifestations of COVID-19 generally show no or only mild inflammation, more detailed data on inflammatory mediators in the CSF of patients with COVID-19 are scarce. Here, we used mass spectrometry to study the proteome, Enzym-linkend immunoassays, semiquantitative cytokine arrays, autoantibody screening, and RNA profiling to study the neuroinflammation. We study the inflammatory response in paired CSF and serum samples of patients with COVID-19 (n=38). Patients with herpes simplex virus encephalitis (HSVE, n=10) and patients with non-inflammatory, non-neurodegenerative neurological diseases (n=28) served as controls. Proteomics on single protein level and subsequent pathway analysis showed similar yet strongly attenuated inflammatory changes in the CSF of COVID-19 patients compared to HSVE patients. CSF/serum indices of interleukin-6, interleukin-16 and CXCL10 together point at an origin from these inflammatory proteins from outside the central nervous system. When stratifying COVID-19 patients into those with and without bacterial superinfection as indicated by elevated procalcitonin levels, inflammatory markers were significantly higher in those with concomitant bacterial superinfection. RNA sequencing in the CSF revealed 101 linear RNAs comprising messenger RNAs, micro RNAs and t-RNA fragments being significantly differentially expressed in COVID-19 than in HSVE or controls. Our findings may explain the absence of signs of intrathecal inflammation upon routine CSF testing despite the presence of SARS-CoV2 infection-associated neurological symptoms. The relevance of blood-derived mediators of inflammation in the CSF for neurological post-COVID-19 symptoms deserves further investigation.

Post-COVID-19 HSV encephalitis: a review.

BACKGROUND: Herpes simplex virus encephalitis (HSVE) is one of the most common infectious causes of sporadic encephalitis. Coronavirus disease (COVID-19) has been associated with immune dysregulation of the host that might increase the risk of infections like HSVE following SARS-CoV-2 infection. There is paucity of literature on post COVID-19 HSVE. This study was conducted with the aim of analyzing the clinical presentation, brain imaging, and outcome of patients presenting with HSVE within 6 weeks of COVID-19 and providing a comprehensive review on the possible mechanisms of post-COVID-19 HSVE. METHODS: This observational study included patients who had laboratory-confirmed HSVE (type 1 or type 2) and a history of COVID-19 within the previous 6 weeks. Patients were followed up for 3 months. RESULTS: Eight patients were included and all of them had type 1 HSVE. The mean latency of onset of neurological symptoms from being diagnosed with COVID-19 is 23.87 days and a majority of the patients have received injectable steroids with a mean duration of 6.5 days. Behavioral abnormality was the commonest neurological presentation and typical brain imaging involved T2 FLAIR hyperintensities of the medial temporal lobes. All patients received intravenous acyclovir 10 mg/kg every eight hourly for atleast 14 days. One patient with concomitant rhinocerebral mucormycosis succumbed while the majority had a complete recovery. CONCLUSION: Possible immune dysregulation in COVID-19 may increase the susceptibility of HSVE in patients with a history of recent SARS-CoV-2 infection. The clinical manifestations and laboratory findings of HSVE in such patients are similar to typical HSVE.

Frequency and burden of neurological manifestations in hospitalized patients with COVID-19: findings from a large Brazilian cohort (preprint)

Background: Scientific data regarding the prevalence of COVID-19 neurological manifestations and prognosis in Latin America countries is still lacking. Therefore, the study aims to understand neurological manifestations of SARS-CoV 2 infection in the Brazilian population and its association with patient outcomes, such as in-hospital mortality. Methods This study is part of the Brazilian COVID-19 Registry, a multicentric COVID-19 cohort, including data from 37 Brazilian hospitals. For the analysis, patients were grouped according to the presence of self-reported vs. clinically-diagnosed neurological manifestations and matched with patients without neurological manifestations by age, sex, number of comorbidities, hospital, and whether or not patients ha neurological underlying disease. Results From 7,232 hospitalized patients with COVID-19, 27.8% presented self-reported neurological manifestations, 9.9% were diagnosed with a clinically-defined neurological syndrome and 1.2% did not show any neurological symptoms. In patients with self-reported symptoms, the most common ones were headache (19.3%), ageusia (10.4%) and anosmia (7.4%). Meanwhile, in the group with clinically-defined neurological syndromes, acute encephalopathy was the most common diagnosis (10.5%), followed by coma (0.6%1) and seizures (0.4%). Men and younger patients were more likely to self-report neurological symptoms, while women and older patients were more likely to develop a neurological syndrome. Patients with clinically-defined neurological syndromes presented a higher prevalence of comorbidities, as well as lower oxygen saturation and blood pressure at hospital admission. In the paired analysis, it was observed that patients with clinically-defined neurological syndromes were more likely to require ICU admission (46.9 vs. 37.9%), mechanical ventilation (33.4 vs. 28.2%), to develop acute heart failure (5.1 vs. 3.0%, p=0.037) and to die (40.7 vs. 32.3%, p<0.001) when compared to controls. Conclusion Neurological manifestations are an important cause of morbidity in COVID-19 patients. More specifically, patients with clinically defined neurological syndromes presented a poorer prognosis for the disease when compared to matched controls.

Neurological manifestations of COVID-19 associated multisystem inflammatory syndrome in adults (MIS-A) (preprint)

Introduction: Multi-system inflammatory syndrome (MIS) is a para infectious or post infectious extra-pulmonary complication of COVID-19. Neurological complications are better described in children with Multi-system inflammatory syndrome (MIS) in children (MIS-C). There is a paucity of literature about the neurological manifestations of Multi-system inflammatory syndrome (MIS) in adults (MIS-A). Materials: and methods Over a 12-month period, from June 2020 to June 2021, over 350 patients were admitted to our medical and COVID ICUs. Of these, eight patients (2.2%) admitted to our ICU were detected to have a neurologic MIS-A. Results: Most patients had a stroke (72.5%). Other manifestations included transverse myelitis, COVID encephalitis, acute encephalopathy, rhabdomyolysis and critical illness myo-neuropathy. Conclusions: Most patients with MIS-A and severe neurological involvement had a poor outcome.

An Autoantigen-ome from HS-Sultan B-Lymphoblasts Offers a Molecular Map for Investigating Autoimmune Sequelae of COVID-19 (preprint)

To understand how COVID-19 may induce autoimmune diseases, we have been compiling an atlas of COVID-autoantigens (autoAgs). Using dermatan sulfate (DS) affinity enrichment of autoantigenic proteins extracted from HS-Sultan lymphoblasts, we identified 362 DS-affinity proteins, of which at least 201 (56%) are confirmed autoAgs. Comparison with available multi-omic COVID data shows that 315 (87%) of the 362 proteins are affected in SARS-CoV-2 infection via altered expression, interaction with viral components, or modification by phosphorylation or ubiquitination, at least 186 (59%) of which are known autoAgs. These proteins are associated with gene expression, mRNA processing, mRNA splicing, translation, protein folding, vesicles, and chromosome organization. Numerous nuclear autoAgs were identified, including both classical ANAs and ENAs of systemic autoimmune diseases and unique autoAgs involved in the DNA replication fork, mitotic cell cycle, or telomerase maintenance. We also identified many uncommon autoAgs involved in nucleic acid and peptide biosynthesis and nucleocytoplasmic transport, such as aminoacyl-tRNA synthetases. In addition, this study found autoAgs that potentially interact with multiple SARS-CoV-2 Nsp and Orf components, including CCT/TriC chaperonin, insulin degrading enzyme, platelet-activating factor acetylhydrolase, and the ezrin-moesin-radixin family. Furthermore, B-cell-specific IgM-associated ER complex (including MBZ1, BiP, heat shock proteins, and protein disulfide-isomerases) is enriched by DS-affinity and up-regulated in B-cells of COVID-19 patients, and a similar IgH-associated ER complex was also identified in autoreactive pre-B1 cells in our previous study, which suggests a role of autoreactive B1 cells in COVID-19 that merits further investigation. In summary, this study demonstrates that virally infected cells are characterized by alterations of proteins with propensity to become autoAgs, thereby providing a possible explanation for infection-induced autoimmunity. The COVID autoantigen-ome provides a valuable molecular resource and map for investigation of COVID-related autoimmune sequelae and considerations for vaccine design.

Purinergic signaling in infectious diseases of the central nervous system.

The incidence of infectious diseases affecting the central nervous system (CNS) has been increasing over the last several years. Among the reasons for the expansion of these diseases and the appearance of new neuropathogens are globalization, global warming, and the increased proximity between humans and wild animals due to human activities such as deforestation. Neurotropism affecting normal brain function is shared by organisms such as viruses, bacteria, fungi, and parasites. Neuroinfections caused by these agents activate immune responses, inducing neuroinflammation, excitotoxicity, and neurodegeneration. Purinergic signaling is an evolutionarily conserved signaling pathway associated with these neuropathologies. During neuroinfections, host cells release ATP as an extracellular danger signal with pro-inflammatory activities. ATP is metabolized to its derivatives by ectonucleotidases such as CD39 and CD73; ATP and its metabolites modulate neuronal and immune mechanisms through P1 and P2 purinergic receptors that are involved in pathophysiological mechanisms of neuroinfections. In this review we discuss the beneficial or deleterious effects of various components of the purinergic signaling pathway in infectious diseases that affect the CNS, including human immunodeficiency virus (HIV-1) infection, herpes simplex virus type 1 (HSV-1) infection, bacterial meningitis, sepsis, cryptococcosis, toxoplasmosis, and malaria. We also provide a description of this signaling pathway in emerging viral infections with neurological implications such as Zika and SARS-CoV-2.

Diagnosing herpes simplex-1 encephalitis at the time of COVID-19 pandemic.

CASE REPORT: We describe the case of a 73-year-old woman who was diagnosed with herpes simplex virus-1 encephalitis during the COVID-19 pandemic. The diagnosis was somehow delayed because relatives were initially cautious in bringing the patient to the hospital and, here, the work-up focus was on coronavirusrelated aspects as the patient was initially reputed to be infected with COVID-19. CONCLUSIONS: During the current viral outbreak, physicians should not neglect the possibility of other diseases that represent neurological emergencies and require immediate recognition and treatment.