Structural implications of SARS-CoV-2 Surface Glycoprotein N501Y mutation within receptor-binding domain [499-505]–computational analysis of the most frequent Asn501 polar uncharged amino acid mutations

The aim of this study was to evaluate the impact of the most frequent Asn501 polar uncharged amino acid mutations upon important structural properties of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) Surface Glycoprotein RBD–hACE2 (human angiotensin-converting enzyme 2) heterodimer. Mutations N501Y, N501T and N501S were considered and their impact upon complex solubility, secondary motifs formation and intermolecular hydrogen bonding interface was analyzed. Results and findings are reported based on 50 ns run in Gromacs molecular dynamics simulation software. Special attention is paid on the biomechanical shifts in the receptor-binding domain (RBD) [499-505]: ProThrAsn(Tyr)GlyValGlyTyr, having substituted Asparagine to Tyrosine at position 501. The main findings indicate that the N501S mutation increases SARS-CoV-2 S-protein RBD–hACE2 solubility over N501T, N501 (wild type): (Formula presented.), (Formula presented.). The N501Y mutation shifts (Formula presented.) -helix S-protein RBD [366-370]: SerValLeuTyrAsn into π-helix for t > 38.5 ns. An S-protein RBD [503-505]: ValGlyTyr shift from (Formula presented.) -helix into a turn is observed due to the N501Y mutation in t > 33 ns. An empirical proof for the presence of a Y501-binding pocket, based on RBD [499-505]: PTYGVGY (Formula presented.) 's RMSF peak formation is presented. There is enhanced electrostatic interaction between Tyr505 (RBD) phenolic -OH group and Glu37 (hACE2) side chain oxygen atoms due to the N501Y mutation. The N501Y mutation shifts the (Formula presented.) hydrogen bond into permanent polar contact;(Formula presented.);(Formula presented.). © 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

GENE ANALYSIS REVEALED THE USEFULNESS OF TRIPLE THERAPY WITH BARICITINIB, RITUXIMAB AND TACROLIMS FOR ANTI-MDA5 ANTIBODY POSITIVE DERMATOMYOSITIS (MDA5-DM)

BackgroundAnti-MDA5 antibody positive dermatomyositis (MDA5-DM) is characterized by high mortality due to rapid progressive ILD. MDA5 is a cytosolic protein and a family of RIG-I like receptor, which functions as a virus RNA sensor and induces the production of such as type-1 IFN. Although little is known about the pathogenesis of MDA5-DM, it is notable that the similarities were reported between COVID-19 infection and MDA5-DM. It may suggest that there is a common underlying autoinflammatory mechanism. We reported that in MDA5-DM, (1) RIG-I-like receptor signaling is enhanced and (2) antiviral responses such as type 1 IFN signaling are also enhanced as compare with anti-ARS-antibody positive DM, and (3) the key for survival is suppression of RIG-I-like and IFN signaling (EULAR2022, POS0390). We also found that a significant role for uncontrolled macrophage in the pathogenesis of ILD by our autopsy case. Recently, it has been reported that tacrolimus (TAC) and cyclophosphamide (CY) combination therapy (TC-Tx) has improved the prognosis of cases with early onset of the disease, but there are cases that cannot be saved. Therefore, we devised BRT therapy (BRT-Tx). The Tx combines baricitinib (BAR), which inhibits GM-CSF and IFN-mediated signaling and effectively suppresses uncontrolled macrophages, with rituximab (RTX) and TAC, which rapidly inhibits B and T cell interaction and ultimately prevents anti-MDA5 antibody production.ObjectivesTo determine the differences in gene expression between BRT and TC-Tx for MDA5-DM in peripheral blood.MethodsTotal of 6 MDA5-DM (TC: 3, BRT: 3) were included and all of them had multiple poor prognostic factors. Peripheral whole blood was collected at just before and 2-3 months after the treatment. RNA was extracted, and quantified using a next-generation sequencer. Differentially Expressed Genes (DEGs) were identified by pre vs. post treatment. Gene Ontology (GO), clustering and Gene Set Variation Analysis (GSVA) were performed to DEGs. As one BRT case was added since our last year's report, we also reanalyzed the surviving vs. fatal cases. The IFN signature was scored separately for Types 1, 2, and 3, and the changes between pre- and post-treatment were investigated.ResultsTwo of three cases with TC died during treatment, while all three cases on BRT recovered. The cluster analysis of the DEGs separated deaths from survivors, not by type of treatment. Comparing surviving and dead cases, GO analysis revealed that the immune system via immunoglobulins and B cells was significantly suppressed in surviving cases. GO analysis of DEGs in each therapeutic group showed that expression of B cell-related genes such as lymphocyte proliferation and B cell receptor signaling pathway were significantly suppressed in BRT-Tx. On the other hand, TC-Tx significantly suppressed such pathways as cell proliferation and cell surface receptor signaling, and was less specific for the target cells than BRT-Tx. The changes in IFN signature score after treatment showed an increase in type 2 and 3 IFN scores in all fatal cases and an increase in type 1 IFN score in one fatal case.ConclusionBRT-Tx significantly suppressed gene expression associated with B cells, while TC-Tx was characterized by low specificity of therapeutic targets and suppression of total cell proliferation. Comparison of surviving and dead cases revealed that the combination of RTX contributed to the success of treatment, as suppression of the immune system mediated by immunoglobulins and B cells is the key for survival. Analysis of the IFN signature revealed an increase in IFN score after treatment in fatal cases, indicating that the combination of BAR is beneficial. The superiority of BRT-Tx seems clear from the fact that all patients survived with BRT-Tx while only one/three patients survived with TC-Tx.REFERENCES:NIL.Acknowledgements:NIL.Disclosure of InterestsMoe Sakamoto: None declared, Yu Nakai: None declared, Yoshiharu Sato: None declared, Yoshinobu Koyama Speakers bureau: Abbvie, Asahikasei, Ayumi, BMS, Esai, Eli-Lilly, Mitsubishi Tanabe, Grant/research support from: Abbvie, GSK.

RETROSPECTIVE STUDY OF VITAMIN D DEFICIENCY IN RHEUMATOLOGIC PATIENTS DURING THE COVID-19 PANDEMIC IN POLAND

BackgroundBefore the COVID-19 pandemic it was estimated that nearly 70% of the population is deficient in vitamin D - 25(OH)D <20ng/ml in Poland [1]. The percentage was expected to increase due to indoor isolation during the COVID-19 pandemic. Vitamin D has a positive effect on the condition of the bones, affects the course of autoimmune diseases, the course of neurological diseases, in type 2 diabetes, vitamin D supplementation improves glucose tolerance and reduces insulin resistance [2,3,4].ObjectivesThe aim of the retrospective study was to determine what percentage of rheumatology clinic patients suffer from vitamin D deficiency and whether this condition is effectively treated.MethodsIn January 2023, a retrospective analysis of the documentation of 172 patients treated at the Rheumatology Outpatient Clinic in Bełżyce (Poland) in 2022 was conducted.ResultsResults: The mean age of the 172 patients whose documentation was analyzed was 60.43 years (min 19, max 88). There were 132 women (76.8%) and 40 men (23.2%) in this group. The mean concentration of vitamin D was 25.57ng/ml±SD11.9 (min 5.7, max 75, Me 22.8). Vitamin D deficiency was found in 44% (serum concentration <20mg/ml), suboptimal concentration (20-30ng/ml) in 31%, optimal concentration (30-50ng/ml) in 21%, and high concentration (>50ng/ml) ml) in 4%. All those with a deficit or deficiency (75 people) were prescribed cholecalciferol in a dose of 20,000 units orally, 1 capsule twice a week after breakfast for 2 months [5]. Patients with optimal vitamin D levels were advised to take a dose of 2,000 units per day. Among the patients with deficit or deficiency, 48 people came for a follow-up visit to check the level of vitamin D (64% of the group with too low vitamin D concentration;28% of the entire group whose documentation was analyzed). In the follow-up examination, the mean concentration of vitamin D was 37.14±9.8ng/ml (min 28, max 84, Me 35.3). Therefore, a statistically significant increase in the concentration of vitamin D in the blood was noted (p<0.05). In the group of people who came for the follow-up examination, there were 35 women, whose mean age was 60.7 years and 13 men (mean age 68.2 years).Conclusion:1. During the COVID-19 pandemic in the group of outpatient rheumatology patients, 75% had a deficiency or suboptimal level of vitamin D.2. Treatment with cholecalciferol in a dose of 20,000 IU twice a week orally for 2 months is effective treatment of vitamin D deficiency.3. Too low percentage of patients diagnosed with vitamin D deficiency come for visits and check-ups.References[1]Hilger J., Friedel A., Herr R.. A systematic review of vitamin D status in populations worldwide. Br J Nutr. 2013;9: 1023.[2]Karczmarewicz E., Czekuć-Kryskiewicz E., Płudowski P. Effect of vitamin D status on pharmacological treatment efficiency-impact on cost- effective management in medicine. Dermatoendocrinology, 2013;5: 299-304.[3]Zhu J., Bing C., Wilding J.P.H. Vitamin d receptor ligands attenuate the inflammatory profile of IL-1β-stimulated human white preadipocytes via modulating the NF-κB and unfolded protein response pathways Biochemical and Biophysical Research Communications 2-18, 503: 1049-1056.[4]Luan W., Hammond L.A. Vuillermot S. Maternal vitamin d prevents abnormal dopaminergic development and function in a mouse model of prenatal immune activation. Scientific Reports 2018;8 (1) article numer 9741.[5]Płudowski P., Karczmarewicz E. i wsp. Witamina D: Rekomendacje dawkowania w populacji osób zdrowych oraz w grupach ryzyka deficytów.Wytyczne dla Europy Środkowej 2013 r. Standardy Medyczne/Pediatria 2013, 10, 573-578 (in Polish).Acknowledgements:NIL.Disclosure of InterestsNone Declared.

Biochemical mechanisms in the severe prognosis of pa- tients with diabetes mellitus infected by SARS-CoV-2 virus: literature review

Diabetes mellitus (DM) is a metabolic disease characterised mainly by signs and symptoms derived from increased serum glucose or hyperglycemia. The coronavirus disease 2019 (COVID-19) pandemic affected the entire world with reports of severe prognosis in diabetic patients infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and high hospital admissions in the intensive care unit (ICU) compared to non-diabetic patients. The objective of the bibliographic review was to evaluate and describe some of the biochemical mechanisms that lead to severe prognosis in patients with DM infected by the SARS-CoV-2 virus through a systematic search for information in different databases. The results showed that the high ICU admission with a severe prognosis of diabetic patients infected by the virus was due to excessive inflammation that causes acute respiratory distress syndrome, cytokine storm, severe pneu-monia, impaired immunity, and hyperglycemia. The virus enters the cell mainly through the endocytic and non-endosomal pathway;the central cellular receptors involved in the mechanisms are insulin receptors (IR), glucose transporter type 2 (GLUT-2), dipeptidyl peptidase-4 (DPP4), glucose transporter type 4 (GLUT-4), glucose converting enzyme angiotensin 2 (ACE2), and the serine transmembrane protease co-receptor 2 (TMPRSS2) essential for viral propagation. The increased susceptibility to devel-oping COVID-19 in diabetic patients is due to the overexpression of ACE2, and serious complications are increased at the microvascular and macrovascular levels, such as nephropathies, neuropathies, and cardiovascular diseases.

THE IMPACT OF IMMUNOMODULATING TREATMENT ON THE SEROLOGICAL IMMUNOGENICITY FOLLOWING THREE DOSES OF COVID-19 VACCINE AND PERSISTENCE OF IMMUNOGENICITY OF TWO VACCINE DOSES IN PATIENTS WITH INFLAMMATORY RHEUMATIC DISEASES - A SWEDISH STUDY (COVID19-REUMA)

BackgroundData on serological immunity after three doses and the long-term immunogenicity (persistence) of COVID-19 vaccine in patients with inflammatory rheumatic diseases (IRD) treated with different immunomodulating drugs are still limited.ObjectivesTo elucidate if 1) a third dose COVID-19 vaccine improves antibody responses, compared to two doses, in patients with IRD treated with biologic or targeted synthetic DMARD (b/tsDMARDs) treatment given as monotherapy or in combination with conventional synthetic DMARDs (csDMARDs) compared to controls, and 2) the persistence of antibody response after two doses of COVID-19 vaccine in IRD patients.MethodsAntibody levels to two antigens representing Spike full length protein and Spike S1 and a Nucleocapsid C-terminal fragment (used to confirm previous COVID-19 infection) were measured in serum samples collected 2-12 and 21-40 weeks after the second vaccine dose and 2-12 weeks after the third dose using a multiplex bead-based serology assay. A sufficient antibody response (seropositivity) was defined as having antibodies over the cut-off level for both spike antigens (1). WT (wild type) anti-Spike IgG and omicron BA.1 and BA.2 variants were measured. Patients with IRD receiving immunomodulating treatment, regularly followed at a rheumatology department and a group of controls were recruited from five Swedish region.ResultsIn total, 323 of 414 patients with IRD and 36 controls who received three vaccine doses participated in this part of the study. Following treatment groups were included: rituximab (n=118;68% female;mean age 67 years), abatacept (n=18;72% female;mean age 64 years), IL6r inhibitors (n=60;73% female;mean age 64 years), JAK-inhibitors (n=44;80% female, mean age 52 years), TNF-inhibitors (n=59;70% female;mean age 47 years;), IL12/23/17 inhibitors (n=24;46% female;mean age 54 years) and controls (n=36;75% female, mean age 51 years). b/ts DMARD treatment was given as monotherapy or in combination with csDMARD, methotrexate (MTX) being the most frequently used csDMARD (32.5%). Compared to results after two vaccine doses, proportion (%) of seropositivity after three vaccine doses increased significantly in groups rituximab +/- DMARD (p=0.003 and p=0.004, respectively), IL6r inhibitors +DMARD (p=0.02), and abatacept+DMARD (p=0.01). However, the proportion of seropositivity after three vaccine doses was still significantly lower in rituximab treated patients (52%) compared to other treatment groups or controls (p<0.001) (Figure 1A/B). Antibody response to WT, omicron sBA.1 and sBA.2 showed similar pattern with the lowest levels among patients treated with rituximab.When antibody response was compared between 2-12 weeks and 21-40 weeks after second dose, the proportion of seropositive rituximab treated patients decreased from 34.9 % to 32.6%. All patients with JAK inhibitors and with JAK-inhibitors and IL6r-inhibitors seropositive 21-40 weeks after the second vaccine dose. Patients treated with other bDMARDs were not included in this analysis due to limited number participants.ConclusionIn this Swedish study including IRD patients receiving different b/t DMARDs, a sufficient immunogenicity of the third dose of COVID-19 vaccine was observed in all treatments with exception for rituximab. However, the increased proportion of seropositivity after the third COVID-19 vaccine doses in rituximab and other patients with insufficient response to two doses including response to the omicron variants, supports the current recommendations on additional booster doses. The immunogenicity of two vaccine doses was preserved to 40 weeks in majority of patients treated with different immunomodulating treatment with exception for rituximab.Figure 1.AcknowledgementsThe study has been supported by the independent research grants from Roche.Disclosure of InterestsMartina Frodlund: None declared, Per Nived: None declared, Katerina Chatzidionysiou Consultant of: consultancy fees from Eli Lilly, AbbVie and Pfizer., Grant/research support from: Research grand from Galapagos, Anna ödergren: None declared, Eva Klingberg: None declared, Monika Hansson: None declared, Elisa Pin: None declared, Lars Klareskog: None declared, Meliha C Kapetanovic Grant/research support from: independent research grants från Pfizer and Roche.

SWITCHING FROM IL-6R ANTAGONISTS TO OLOKIZUMAB, A DIRECT IL-6 INHIBITOR

BackgroundOlokizumab (OKZ), an IL-6 ligand inhibitor in doses of 64 mg every two weeks (q2w) or every 4 weeks (q4w) demonstrated significant improvements in signs and symptoms of RA. Due to lack of availability of the IL-6 receptor antagonists tocilizumab and sarilumab in the pandemic COVID-19 situation, RA patients (pts) were switched to OKZ as a registered drug in Russia in 2022.ObjectivesTo investigate safety and efficacy of OKZ after switching from an IL-6 receptor inhibitor in clinical practice.MethodsThis retrospective cohort study included available efficacy and safety data of OKZ in pts with RA after switching from tocilizumab (IV or SC) or sarilumab (SC) from 11 of participating centers.Efficacy assessments and routine biochemical data were analyzed using descriptive statistics – mean with standard deviation for continuous parameters and absolute and relative frequency for binary variables. AE were reported by participating centers according to pt's files. The statistical significance of data of the analyzed variable at a particular visit compared with previous visits or with the Switch visit was determined using paired t-test. Fisher's exact test or chi-square test was used to compare the proportion of pts with improvement/no change and worsening. All tests were 2-tailed, and a p-value <0.050 was considered statistically significant. As this is an observational study, the statistical criteria have not been pre-specified and therefore the data presented cannot be considered definitive but should be confirmed in future analyses.ResultsEfficacy and safety results were collected for 110 RA pts with a mean age of 47.8 (15.7) years, including 87 (79.1%) women. 77 (70.0%) pts were RF/ACPA positive. Mean RA duration was 13.1 (8.9) years and mean duration of treatment with an IL-6 receptor antagonist was 47.8 (30.0) months. Mean interval before switching was 54.7 (35.4) days with the main reason of unavailable IL6-R antagonist. Pts were treated with OKZ 64 mg q4w SC.Before initiation of OKZ, an increase of DAS28-CRP was observed due to a prolonged period after the last injection of the IL-6R inhibitor from 2.8 to 3.1 weeks in 32 pts on monotherapy who were transferred to OKZ faster (on average after 41.6 (23.8) days), and from 2.7 to 3.3 weeks in 73 pts on concomitant sDMARDs (60.0 (38.0) days). DAS28-CRP was improved to 2.8 on the second OKZ visit (S+1) in both groups. Response to OKZ was maintained over a period of 2 months with no difference between pts previously receiving an IL-6 R antagonist. Of note, lower disease activity based on DAS28-CRP of 2.5 and 2.6 was achieved after 8 weeks (S+2) of OKZ therapy compared to the previous IL-6R inhibitors treatment S-1 visit (P less 0.05) (Figure 1).Figure 1.Mean DAS28CRP over time, M(SD)[Figure omitted. See PDF]Abbreviation: S-2 and S-1 last visits before switching– S+1 and S+2 visits after switching,Treatment emergent AE occurred in 7 (6.4%) pts, the most common AE in 3 pts (2.7%) included arthralgia of hands and feet and transient leukopenia in 2 (1.8%) pts.Serious AE were reported by 1 (0.9%) pt (exacerbation of herpes infection that led to treatment discontinuation). No deaths were reported. There were no apparent differences in safety and efficacy outcomes between pts on OKZ monotherapy compared to combined treatment with csDMARDs. Only one pt was switched back to tocilizumab when it became available.Table 1.Summary of treatment emergent adverse events (safety population)NOKZ 64 mg q4w with MTX N=78OKZ 64 mg q4w monotherapy N=32Any AE51 carpal canal syndromeAny serious AE10Any AE leading to discontinuation of study drug10Any death00Any AE of special interest10Infections10Laboratory abnormalitiesHyperbilirubin-emiaALT, AST elevation less than 3 ULNALT, alanine transaminase;AST, aspartate transaminase;ULN, upper limit of normalConclusionIn pts with RA responding to an IL-6R antagonist, switching to OKZ was safe and well tolerated in clinical practice. The treatment response was maintained and in some pts disease activity moderately decreased in compariso to baseline level both in OKZ mono and combination therapy.Reference[1]J.Smolen, N Engl J Med 2022;387:715-726AcknowledgementsI have acknowledgements to Vinogradova I.B., Anoshenkova O.N., Antipova O.V., Baranov A.A., Bogdanova E.A., Grabovetskaya Y.Y., Ilivanova E.P.,Kalyagin A.N., Kushnir I.N., Lapkina N.A. Mokrousova M.V., Nesmeyanova O.B., Nikitina N.V., Shesternya P.A. and Yudina N.V.Disclosure of InterestsEugen Feist Consultant of: Abbvie, Eli Lilly, Galapagos, Medac, Novartis, Sanofi, Sobi, R-Pharm, Grant/research support from: Eli Lilly, Novartis, Pfizer, Evgeny Nasonov Consultant of: AbbVie, Eli Lilly, Janssen, Novartis, Pfizer.

Targeting TLR-4 Signaling to Treat COVID-19-induced Acute Kidney Injury

The newly discovered severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) has turned into a potentially fatal pandemic illness. Numerous acute kidney injury (AKI) cases have been reported, although diffuse alveolar destruction and acute respiratory failure are the major symptoms of SARS-CoV-2 infection. The AKI, often known as a sudden loss of kidney function, carries a greater risk of mortality and morbidity. AKI was the second most frequent cause of death after acute respiratory distress syndrome (ARDS) in critically ill patients with coronavirus disease 2019 (COVID-19). While most patients with COVID-19 have moderate symptoms, some have severe symptoms, such as septic shock and ARDS. Also, it has been proven that some patients have severe symptoms, such as the failure of several organs. The kidneys are often affected either directly or indirectly. The major signs of kidney involvement are proteinuria and AKI. It is hypothesized that multiple mechanisms contribute to kidney injury in COVID-19. Direct infection of podocytes and proximal tubular cells in the kidneys may lead to acute tubular necrosis and collapsing glomerulopathy. SARS-CoV2 may also trigger a cascade of immunological responses that lead to AKI, including cytokine storm (CS), macrophage activation syndrome, and Toll-like receptor type-4 activation (TLR-4). Other proposed processes of AKI include interactions between organs, endothelial failure, hypercoagulability, rhabdomyolysis, and sepsis.Furthermore, ischemic damage to the kidney might result from the decreased oxygen supply. This article focuses on kidney injury's epidemiology, etiology, and pathophysiological processes. Specifically, it focuses on the CS and the role of TLR-4 in this process. To effectively manage and treat acute kidney damage and AKI in COVID-19, it is crucial to understand the underlying molecular pathways and pathophysiology.

Discussed Poster Abstracts – PM1

B PM1-030 b B Adverse drug reaction profile of drug interactions involving a protein kinase inhibitor indicated in chronic myeloid leukemia from pharmacovigilance databases b M. C. Pajiep, M. Lapeyre-Mestre and F. Despas I Centre Hospitalier Universitaire (CHU) de Toulouse, France i B Introduction: b The introduction of protein kinase inhibitors (PKIs) for chronic myeloid leukemia (CML) has considerably improved prognosis of the disease but has also demonstrated a great potential for drug-drug interactions. Service de Médecine Interne et Infectiologie, Groupe Hospitalier Diaconesses-Croix Saint-Simon, Paris, France i B Introduction: b Despite an important drug-drug interaction, it was previously suggested the clindamycin-rifampicin combination could be used in patients with bone and joints infections (BJIs) provided clindamycin is administered by continuous infusion. Most of eligible patients to the antiviral drug can benefit from it despite the risk of drug-drug interaction. Twenty patients received clindamycin without rifampicin, 19 patients received clindamycin concomitantly with rifampicin and the remaining 85 received clindamycin successively without and with rifampicin. B Results: b Among 957 patients treated with anti-PD-1/PD-L1 during the data collection period, 686 patients were included: 430 new users of a SD regimen, 161 patients who started with SD and switched to ED regimen during follow-up, and 95 new users of an ED regimen. [Extracted from the article] Copyright of Fundamental & Clinical Pharmacology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

How Toll-like receptors influence Parkinson's disease in the microbiome-gut-brain axis.

Recently, a large number of experimenters have found that the pathogenesis of Parkinson's disease may be related to the gut microbiome and proposed the microbiome-gut-brain axis. Studies have shown that Toll-like receptors, especially Toll-like receptor 2 (TLR2) and Toll-like receptor 4 (TLR4), are key mediators of gut homeostasis. In addition to their established role in innate immunity throughout the body, research is increasingly showing that the Toll-like receptor 2 and Toll-like receptor 4 signaling pathways shape the development and function of the gut and enteric nervous system. Notably, Toll-like receptor 2 and Toll-like receptor 4 are dysregulated in Parkinson's disease patients and may therefore be identified as the core of early gut dysfunction in Parkinson's disease. To better understand the contribution of Toll-like receptor 2 and Toll-like receptor 4 dysfunction in the gut to early α-synuclein aggregation, we discussed the structural function of Toll-like receptor 2 and Toll-like receptor 4 and signal transduction of Toll-like receptor 2 and Toll-like receptor 4 in Parkinson's disease by reviewing clinical, animal models, and in vitro studies. We also present a conceptual model of the pathogenesis of Parkinson's disease, in which microbial dysbiosis alters the gut barrier as well as the Toll-like receptor 2 and Toll-like receptor 4 signaling pathways, ultimately leading to a positive feedback loop for chronic gut dysfunction, promoting α-synuclein aggregation in the gut and vagus nerve.

Antiviral response and immunopathogenesis of interleukin 27 in COVID-19.

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with a high mortality rate. The clinical course is attributed to the severity of pneumonia and systemic complications. In COVID-19 patients and murine models of SARS-CoV-2 infection, the disease may be accompanied by excessive production of cytokines, leading to an accumulation of immune cells in affected organs such as lungs. Previous reports have shown that SARS-CoV-2 infection antagonizes interferon (IFN)-dependent antiviral response, thereby preventing the expression of IFN-stimulated genes (ISGs). Lower IFN levels have been linked to more-severe COVID-19. Interleukin 27 (IL27) is a heterodimeric cytokine composed of IL27p28 and EBI3 subunits, which induce both pro- and anti-inflammatory responses. Recently, we and others have reported that IL27 also induces a strong antiviral response in an IFN-independent manner. Here, we investigated transcription levels of both IL27 subunits in COVID-19 patients. The results show that SARS-CoV-2 infection modulates TLR1/2-MyD88 signaling in PBMCs and monocytes and induces NF-κB activation and expression of NF-κB-target genes that are dependent on a robust pro-inflammatory response, including EBI3; and activates IRF1 signaling which induces IL27p28 mRNA expression. The results suggest that IL27 induces a robust STAT1-dependent pro-inflammatory and antiviral response in an IFN-independent manner in COVID-derived PBMCs and monocytes as a function of a severe clinical course of COVID-19. Similar results were observed in macrophages stimulated with the SARS-CoV-2 spike protein. Thus, IL27 can trigger an antiviral response in the host, suggesting the possibility of novel therapeutics against SARS-CoV-2 infection in humans.

Recombinant SARS-CoV-2 Spike Protein Stimulates Secretion of Chymase, Tryptase, and IL-1ß from Human Mast Cells, Augmented by IL-33.

SARS-CoV-2 infects cells via its spike (S) protein binding to its surface receptor angiotensin-converting enzyme 2 (ACE2) and results in the production of multiple proinflammatory cytokines, especially in the lungs, leading to what is known as COVID-19. However, the cell source and the mechanism of secretion of such cytokines have not been adequately characterized. In this study, we used human cultured mast cells that are plentiful in the lungs and showed that recombinant SARS-CoV-2 full-length S protein (1-10 ng/mL), but not its receptor-binding domain (RBD), stimulates the secretion of the proinflammatory cytokine interleukin-1ß (IL-1ß) as well as the proteolytic enzymes chymase and tryptase. The secretion of IL-1ß, chymase, and tryptase is augmented by the co-administration of interleukin-33 (IL-33) (30 ng/mL). This effect is mediated via toll-like receptor 4 (TLR4) for IL-1ß and via ACE2 for chymase and tryptase. These results provide evidence that the SARS-CoV-2 S protein contributes to inflammation by stimulating mast cells through different receptors and could lead to new targeted treatment approaches.

Dual role of glycans and binding receptors in pathogenesis of enveloped viruses (by mainly focusing on two recent pandemics).

A period of about a decade has been estimated to pass for the emergence of a new infectious strain of a virus that may lead to the occurrence of a pandemic one. It is now suggested that the variants of the 1918 H1N1 and coronavirus disease-19 pandemics could have existed in humans after the initial cross-species introduction to humans and underwent multiple low-level seasonal epidemics before the occurrence of their outbreaks. They share similarities in the continuation, widespreadness due to high transmissibility, high fatality rate and clinical symptoms. They are assumed to share a similar principle of a zoonotic source and a cross-species pathway for transmission. They show some similarities in their pathogenesis with other enveloped viruses: Severe Acute Respiratory Syndrome Coronavirus-1 (SARS-CoV-1), Middle East respiratory syndrome coronavirus (MERS-CoV), human immunodeficiency virus, Ebola, Lassa and measles viruses. The highly pathogenic nature of these viruses and their genetic variants may depend on their binding affinity for host cell receptors, whereby they efficiently circumvent or block host cell immune responses triggered by cytokines (interferon). High transmission rates and viral pathogenicity are attributed to glycan moieties that facilitate virus binding to host multiple receptors and cell entry, thereby helping viruses to evade immune recognition and response. Also, mucosa glycotopes are a matter of concern that play as primary sites for virus attachment and body entry. Finding general lectins or ligands that block the viral-host receptors interaction or identifying individual glycotopes is the therapeutic and prognosis topic that demands the main focus.

COVID-19-Related Long-Term Taste Impairment: Symptom Length, Related Taste, Smell Disturbances, and Sample Characteristics.

INTRODUCTION:  The COVID-19 infection triggered in some patients a prolonged reduction in the perception of both gustatory and olfactory senses (ageusia and anosmia). These symptoms could be manifested during the first days after the contagion, acting as predictors of COVID-19 infection, and additionally, they could be the only symptoms manifested at all. Clinical resolution of anosmia and ageusia was expected to occur within a few weeks, yet in some cases, patients began to demonstrate COVID-19-related long-term taste impairment (CRLTTI), a condition that can persist for longer than two months, contradicting initial evidence.  Objectives: The authors' aimed to describe the characteristics of the sample of 31 participants with COVID-19-related long-term taste impairment, and their capacity to quantify taste and rate their smell perception.  Material and Methods: Participants were submitted to a taste evaluation of four hyper-concentrated tastes perceived by the tongue (0-10), self-reported their smell (0-10), and answered a semi-structured questionnaire.  Results: Different tastes seemed to be affected differently by COVID-19, despite the lack of statistical relevance observed in this study. Dysgeusia was only expressed in bitter, sweet, and acidic tastes. The mean age observed was 40.2 (SD 12.06) years, with women representing 71% of the sample. Taste impairment persisted for an average period of 10.8 months (SD 5.7). Self-reported smell impairment was reported by the majority of participants with taste impairment. Non-vaccinated people represented 80.6% of the sample.  Conclusions: COVID-19 infection could trigger taste and smell disturbances that lasted as long as 24 months. CRLTTI seems not to affect the four main taste perceptions (hyper-concentrated) equally. Women represented the majority of the sample, with an average age of 40 years (SD 12.06). Previous diseases, medication use, and behavioral aspects seem not to be linked to CRLTTI development.

Comment on: 'Should We Interfere with the Interleukin-6 Receptor During COVID-19: What Do We Know?'/Authors' Reply to Chia Siang Kow et al.: Comment on: 'Should We Interfere with the Interleukin-6 Receptor During COVID-19: What Do We Know So Far?'

[...]the mortality reduction has previously been reported in the prospective meta-analysis [2] conducted by The WHO Rapid Evidence Appraisal for COVID-19 Therapies (REACT) Working Group. Nonetheless, owing to relatively scarce evidence, it is still unclear whether monoclonal IL-6 antibodies reduce mortality in patients with COVID-19, similar to the IL-6 receptor inhibitors. [...]large-scale randomised trials should also be conducted to establish the role of monoclonal IL-6 antibodies in the treatment of COVID-19. [...]among hypothetical long-term complications, peripheral neuropathy would also be noticeable [10] and may contribute to the broad long COVID pattern. [...]there is a theoretical risk of altering the efficacy of immune checkpoint inhibitors during tumour disease management [11].

Essential Multiorgan Pathophysiology of COVID-19

Typical manifestations of coronavirus disease-2019 (COVID-19) include mild-to-moderate "flu-like” symptoms, although more severe manifestations have been reported. The pathophysiology of COVID-19 is complex, and its clinical spectrum might not be limited to local pneumonia, but rather may represent a multisystem illness with potential for severe acute respiratory distress syndrome (ARDS) and multiorgan impairment. In this context, the aim of the present handbook is to provide an overview of possible multisystemic manifestations and therapeutic strategies, in order to guide the clinician to deal with COVID-19 critical illness and to prevent potential systemic consequences. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2022.

Bioinformatic Screening of Compounds from Iranian Lamiaceae Family Members against SARS-CoV-2 Spike Protein

Background: COVID-19 (coronavirus disease 2019) is still a major challenge worldwide. The disease is caused by binding the coronavirus to ACE2 receptors on lung cells, infecting the cells and triggering the onset of symptoms. The prevention of such a binding in which the virus is eventually unable to enter the cell could be a promising therapeutic approach.Methods: In this in silico study, 306 compounds of Lamiaceae family native in Iran (native Mints) were retrieved from several databases as 3D structures, and after that molecular docking and virtual screening, the compounds with inhibitory potential were selected in terms of free energy binding against the spike protein of the virus. The pharmacokinetic profile of selected compounds was evaluated, and by molecular dynamic simulation and MM/PBSA, four compounds were further assessed for binding affinities against the receptor-binding domain of the spike.Results: The results showed the Catechin gallate and Perovskone B from Stachys and Salvia genus generated a stronger binding affinity, and therefore could act as potential inhibitory compounds of RBD of the SARS-CoV-2 spike protein.Conclusion: This study revealed that some members of the Lamiaceae family could be employed to inhibit SARS-CoV-2 activity through interaction with spike protein and therefore could be used for further investigation in vitro and in vivo.

Role of toll-like receptors in the pathogenesis of COVID-19: Current and future perspectives

The coronavirus disease 2019 (COVID-19) pandemic underlines a persistent threat of respiratory tract infectious diseases and warrants preparedness for a rapid response. At present, COVID-19 has had a serious social impact and imposed a heavy global burden on public health. The exact pathogenesis of COVID-19 has not been fully elucidated. Since the outbreak of COVID-19, a renewed attention has been brought to Toll-like receptors (TLRs). Available data and new findings have demonstrated that the interaction of human TLRs and SARS-CoV-2 is a vital mediator of COVID-19 immunopathogenesis. TLRs such as TLR2, 4, 7 and 8 are potentially important in viral combat and activation of immunity in patients with COVID-19. Therapeutics targeting TLRs are currently considered promising options against the pandemic. A number of TLR-targeting immunotherapeutics are now being investigated in preclinical studies and different phases of clinical trials. In addition, innovative vaccines based on TLRs under development could be a promising approach for building a new generation of vaccines to solve the current challenges. In this review, we summarize recent progress in the role of TLRs in COVID-19, focusing the new candidate drugs targeting TLRs, the current technology and potential paths forward for employing TLR agonists as vaccine adjuvants.Copyright © 2023 The Scandinavian Foundation for Immunology.

Drug–Target Interaction Deep Learning-Based Model Identifies the Flavonoid Troxerutin as a Candidate TRPV1 Antagonist

Based on the advances made by artificial intelligence (AI) technologies in drug discovery, including target identification, hit molecule identification, and lead optimization, this study investigated natural compounds that could act as transient receptor potential vanilloid 1 (TRPV1) channel protein antagonists. Using a molecular transformer drug–target interaction (MT-DTI) model, troxerutin was predicted to be a TRPV1 antagonist at IC50 582.73 nM. In a TRPV1-overexpressing HEK293T cell line, we found that troxerutin antagonized the calcium influx induced by the TRPV1 agonist capsaicin in vitro. A structural modeling and docking experiment of troxerutin and human TRPV1 confirmed that troxerutin could be a TRPV1 antagonist. A small-scale clinical trial consisting of 29 participants was performed to examine the efficacy of troxerutin in humans. Compared to a vehicle lotion, both 1% and 10% w/v troxerutin lotions reduced skin irritation, as measured by skin redness induced by capsaicin, suggesting that troxerutin could ameliorate skin sensitivity in clinical practice. We concluded that troxerutin is a potential TRPV1 antagonist based on the deep learning MT-DTI model prediction. The present study provides a useful reference for target-based drug discovery using AI technology and may provide useful information for the integrated research field of AI technology and biology.

Current Status and Prospects of Vaccines based on DDS Technology

The development of DDS technology has contributed critically to the unprecedentedly rapid requirement for vaccines against COVID-19. LNP-based mRNA vaccines represent a subset of emerging DDS technology. Despite the groundbreaking nature of these vaccines, they are yet to be perfected and as such, new technologies are being developed to optimize these vaccines. This review will focus on exploring one of the modalities of recombinant protein vaccines and will introduce various findings on the enhancement of vaccine efficacy using antigen modification technologies, including VLPs and Fc-fusion proteins, and adjuvant improvements.Alternate :抄録COVID-19に対してかつてない速度でワクチンが普及した背景には、DDS技術の発展が必要不可欠であった。特に、mRNAワクチンにおける脂質ナノ粒子（LNP）の開発は、まさにDDS技術の結集といえよう。一方で、mRNAワクチンを含め、現状のさまざまなワクチンは多くの課題を有しており、より効果的かつ安全なワクチン開発に資する基盤技術の確立が世界的に待望されている。本稿では、ワクチンモダリティの1つである組換えタンパク質ワクチンに焦点を絞り、抗原改変技術からアジュバントの改良に至るまで、ワクチン開発基盤技術の最新知見について紹介する。