The interaction of inflammasomes and gut microbiota: novel therapeutic insights.

Inflammasomes are complex platforms for the cleavage and release of inactivated IL-1ß and IL-18 cytokines that trigger inflammatory responses against damage-associated molecular patterns (DAMPs) or pathogen-associated molecular patterns (PAMPs). Gut microbiota plays a pivotal role in maintaining gut homeostasis. Inflammasome activation needs to be tightly regulated to limit aberrant activation and bystander damage to the host cells. Several types of inflammasomes, including Node-like receptor protein family (e.g., NLRP1, NLRP3, NLRP6, NLRP12, NLRC4), PYHIN family, and pyrin inflammasomes, interact with gut microbiota to maintain gut homeostasis. This review discusses the current understanding of how inflammasomes and microbiota interact, and how this interaction impacts human health. Additionally, we introduce novel biologics and antagonists, such as inhibitors of IL-1ß and inflammasomes, as therapeutic strategies for treating gastrointestinal disorders when inflammasomes are dysregulated or the composition of gut microbiota changes.

Endoscopic retrograde cholangiopancreatography utilisation and outcomes in the first advanced endoscopy centre in Palestine at Al-Ahli Hospital: a retrospective cohort study.

OBJECTIVE: To evaluate the utilisation and outcomes of endoscopic retrograde cholangiopancreatography (ERCP) procedures, success rates, incidence and risk factors for procedural-related complications in a single centre-based study. STUDY DESIGN: Retrospective cohort study. SETTING: First advanced tertiary endoscopy centre in Palestine. PARTICIPANTS: A total of 1909 procedures on 1303 patients were included in the analysis: females were 57.9% of the cases (n=755), 1225 patients (94%) were from West Bank and Jerusalem and 78 (6%) were from Gaza Strip. All patients who underwent ERCP throughout the period from December 2017 to September 2022 were selected to participate in the study. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcomes of interest in our analysis were success rates, procedural outcomes and post- procedural complications including pancreatitis, bleeding and others. Two multivariate logistic regression models were performed to calculate the risk of post-ERCP complications and post-ERCP pancreatitis (PEP) in patients with certain risk factors like demographic factors, procedural techniques' variation, pancreatic duct manipulations and others. We also discussed the management of the failed procedures. RESULTS: The overall complication rate was 5%, including PEP (n=43, 2.3%), infection/cholangitis (n=20, 1%), bleeding (n=9, 0.5%) and perforation (n=7, 0.4%). The mortality rate was 0.6% (n=11). Risk factors for adverse events included pancreatic duct cannulation and PEP (p<0.001, OR=3.64). Additionally, younger patients (≤45) were found to carry a higher risk for PEP when compared with older patients (≥65) (p=0.023, OR=2.84). In comparison with sphincterotomy, the double-wire technique was associated with a higher risk of complications (p=0.033, OR=2.29). CONCLUSIONS: We summarised the utilisation and outcomes of ERCP among the Palestinian population in the first advanced centre in Palestine. Cannulation success rates are similar to the established standards and are acceptable compared with other centres worldwide. Perioperative complication rates of ERCP remain infrequent, and death is quite unusual and thus considered a safe procedure.

COVID-19 therapeutics: stewardship in England and considerations for antimicrobial resistance.

The COVID-19 pandemic saw unprecedented resources and funds driven into research for the development, and subsequent rapid distribution, of vaccines, diagnostics and directly acting antivirals (DAAs). DAAs have undeniably prevented progression and life-threatening conditions in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, there are concerns of antimicrobial resistance (AMR), antiviral resistance specifically, for DAAs. To preserve activity of DAAs for COVID-19 therapy, as well as detect possible mutations conferring resistance, antimicrobial stewardship and surveillance were rapidly implemented in England. This paper expands on the ubiquitous ongoing public health activities carried out in England, including epidemiologic, virologic and genomic surveillance, to support the stewardship of DAAs and assess the deployment, safety, effectiveness and resistance potential of these novel and repurposed therapeutics.

Neuroinflammation, autoinflammation, splenomegaly and anemia caused by bi-allelic mutations in IRAK4.

We describe a novel, severe autoinflammatory syndrome characterized by neuroinflammation, systemic autoinflammation, splenomegaly, and anemia (NASA) caused by bi-allelic mutations in IRAK4. IRAK-4 is a serine/threonine kinase with a pivotal role in innate immune signaling from toll-like receptors and production of pro-inflammatory cytokines. In humans, bi-allelic mutations in IRAK4 result in IRAK-4 deficiency and increased susceptibility to pyogenic bacterial infections, but autoinflammation has never been described. We describe 5 affected patients from 2 unrelated families with compound heterozygous mutations in IRAK4 (c.C877T (p.Q293*)/c.G958T (p.D320Y); and c.A86C (p.Q29P)/c.161 + 1G>A) resulting in severe systemic autoinflammation, massive splenomegaly and severe transfusion dependent anemia and, in 3/5 cases, severe neuroinflammation and seizures. IRAK-4 protein expression was reduced in peripheral blood mononuclear cells (PBMC) in affected patients. Immunological analysis demonstrated elevated serum tumor necrosis factor (TNF), interleukin (IL) 1 beta (IL-1ß), IL-6, IL-8, interferon α2a (IFN-α2a), and interferon ß (IFN-ß); and elevated cerebrospinal fluid (CSF) IL-6 without elevation of CSF IFN-α despite perturbed interferon gene signature. Mutations were located within the death domain (DD; p.Q29P and splice site mutation c.161 + 1G>A) and kinase domain (p.Q293*/p.D320Y) of IRAK-4. Structure-based modeling of the DD mutation p.Q29P showed alteration in the alignment of a loop within the DD with loss of contact distance and hydrogen bond interactions with IRAK-1/2 within the myddosome complex. The kinase domain mutation p.D320Y was predicted to stabilize interactions within the kinase active site. While precise mechanisms of autoinflammation in NASA remain uncertain, we speculate that loss of negative regulation of IRAK-4 and IRAK-1; dysregulation of myddosome assembly and disassembly; or kinase active site instability may drive dysregulated IL-6 and TNF production. Blockade of IL-6 resulted in immediate and complete amelioration of systemic autoinflammation and anemia in all 5 patients treated; however, neuroinflammation has, so far proven recalcitrant to IL-6 blockade and the janus kinase (JAK) inhibitor baricitinib, likely due to lack of central nervous system penetration of both drugs. We therefore highlight that bi-allelic mutation in IRAK4 may be associated with a severe and complex autoinflammatory and neuroinflammatory phenotype that we have called NASA (neuroinflammation, autoinflammation, splenomegaly and anemia), in addition to immunodeficiency in humans.

Generation of SARS-CoV-2 escape mutations by monoclonal antibody therapy.

COVID-19 patients at risk of severe disease may be treated with neutralising monoclonal antibodies (mAbs). To minimise virus escape from neutralisation these are administered as combinations e.g. casirivimab+imdevimab or, for antibodies targeting relatively conserved regions, individually e.g. sotrovimab. Unprecedented genomic surveillance of SARS-CoV-2 in the UK has enabled a genome-first approach to detect emerging drug resistance in Delta and Omicron cases treated with casirivimab+imdevimab and sotrovimab respectively. Mutations occur within the antibody epitopes and for casirivimab+imdevimab multiple mutations are present on contiguous raw reads, simultaneously affecting both components. Using surface plasmon resonance and pseudoviral neutralisation assays we demonstrate these mutations reduce or completely abrogate antibody affinity and neutralising activity, suggesting they are driven by immune evasion. In addition, we show that some mutations also reduce the neutralising activity of vaccine-induced serum.

A conserved glutathione binding site in poliovirus is a target for antivirals and vaccine stabilisation.

Strategies to prevent the recurrence of poliovirus (PV) after eradication may utilise non-infectious, recombinant virus-like particle (VLP) vaccines. Despite clear advantages over inactivated or attenuated virus vaccines, instability of VLPs can compromise their immunogenicity. Glutathione (GSH), an important cellular reducing agent, is a crucial co-factor for the morphogenesis of enteroviruses, including PV. We report cryo-EM structures of GSH bound to PV serotype 3 VLPs showing that it can enhance particle stability. GSH binds the positively charged pocket at the interprotomer interface shown recently to bind GSH in enterovirus F3 and putative antiviral benzene sulphonamide compounds in other enteroviruses. We show, using high-resolution cryo-EM, the binding of a benzene sulphonamide compound with a PV serotype 2 VLP, consistent with antiviral activity through over-stabilizing the interprotomer pocket, preventing the capsid rearrangements necessary for viral infection. Collectively, these results suggest GSH or an analogous tight-binding antiviral offers the potential for stabilizing VLP vaccines.

Production and Characterisation of Stabilised PV-3 Virus-like Particles Using Pichia pastoris.

Following the success of global vaccination programmes using the live-attenuated oral and inactivated poliovirus vaccines (OPV and IPV), wild poliovirus (PV) is now only endemic in Afghanistan and Pakistan. However, the continued use of these vaccines poses potential risks to the eradication of PV. The production of recombinant PV virus-like particles (VLPs), which lack the viral genome offer great potential as next-generation vaccines for the post-polio world. We have previously reported production of PV VLPs using Pichia pastoris, however, these VLPs were in the non-native conformation (C Ag), which would not produce effective protection against PV. Here, we build on this work and show that it is possible to produce wt PV-3 and thermally stabilised PV-3 (referred to as PV-3 SC8) VLPs in the native conformation (D Ag) using Pichia pastoris. We show that the PV-3 SC8 VLPs provide a much-improved D:C antigen ratio as compared to wt PV-3, whilst exhibiting greater thermostability than the current IPV vaccine. Finally, we determine the cryo-EM structure of the yeast-derived PV-3 SC8 VLPs and compare this to previously published PV-3 D Ag structures, highlighting the similarities between these recombinantly expressed VLPs and the infectious virus, further emphasising their potential as a next-generation vaccine candidate for PV.

Assessment of Human Leukocyte Antigen Differences between Smokers with Reinke's Edema and Those with Laryngeal Cancer.

Introduction: The present study aimed to assess human leukocyte antigen (HLA) typing differences between smokers with Reinke's edema and those with laryngeal squamous cell carcinoma (SCC). Materials and Methods: The HLA class I, II alleles were examined in 76 unrelated Iranian patients using low-resolution polymerase chain reaction with the sequence-specific primer (PCR-SSP) method. Results: The frequency of the HLA-A*36 allele and HLA-B*35 was significantly higher in patients with SCC. The frequency of HLA-DRB1*01 alleles in Reinke's edema was significantly higher, as compared to that in others. In the volunteer group, HLA-DRB1*13 and HLA-DRB1*15 were significantly higher. Conclusions: As evidenced by the obtained results, HLA-A*36 was significantly higher in SCC, as compared to that in volunteers and Reinke's edema patients. It can be concluded that being positive for HLA-A*36 increases the chance of SCC by three times. This result should be further investigated in cohort studies conducted on larger samples. Furthermore, HLA-A*24 was significantly higher in the volunteer group, as compared to that in other groups. The HLADRB1*01 was remarkably higher in Reinke's edema, as compared to that in SCC.

SARS-CoV-2 Omicron-B.1.1.529 leads to widespread escape from neutralizing antibody responses.

On 24th November 2021, the sequence of a new SARS-CoV-2 viral isolate Omicron-B.1.1.529 was announced, containing far more mutations in Spike (S) than previously reported variants. Neutralization titers of Omicron by sera from vaccinees and convalescent subjects infected with early pandemic Alpha, Beta, Gamma, or Delta are substantially reduced, or the sera failed to neutralize. Titers against Omicron are boosted by third vaccine doses and are high in both vaccinated individuals and those infected by Delta. Mutations in Omicron knock out or substantially reduce neutralization by most of the large panel of potent monoclonal antibodies and antibodies under commercial development. Omicron S has structural changes from earlier viruses and uses mutations that confer tight binding to ACE2 to unleash evolution driven by immune escape. This leads to a large number of mutations in the ACE2 binding site and rebalances receptor affinity to that of earlier pandemic viruses.

Mammalian expression of virus-like particles as a proof of principle for next generation polio vaccines.

Global vaccination programs using live-attenuated oral and inactivated polio vaccine (OPV and IPV) have almost eradicated poliovirus (PV) but these vaccines or their production pose significant risk in a polio-free world. Recombinant PV virus-like particles (VLPs), lacking the viral genome, represent safe next-generation vaccines, however their production requires optimisation. Here we present an efficient mammalian expression strategy producing good yields of wild-type PV VLPs for all three serotypes and a thermostabilised variant for PV3. Whilst the wild-type VLPs were predominantly in the non-native C-antigenic form, the thermostabilised PV3 VLPs adopted the native D-antigenic conformation eliciting neutralising antibody titres equivalent to the current IPV and were indistinguishable from natural empty particles by cryo-electron microscopy with a similar stabilising lipidic pocket-factor in the VP1 ß-barrel. This factor may not be available in alternative expression systems, which may require synthetic pocket-binding factors. VLPs equivalent to these mammalian expressed thermostabilized particles, represent safer non-infectious vaccine candidates for the post-eradication era.

Omicron-B.1.1.529 leads to widespread escape from neutralizing antibody responses.

On the 24 th November 2021 the sequence of a new SARS CoV-2 viral isolate spreading rapidly in Southern Africa was announced, containing far more mutations in Spike (S) than previously reported variants. Neutralization titres of Omicron by sera from vaccinees and convalescent subjects infected with early pandemic as well as Alpha, Beta, Gamma, Delta are substantially reduced or fail to neutralize. Titres against Omicron are boosted by third vaccine doses and are high in cases both vaccinated and infected by Delta. Mutations in Omicron knock out or substantially reduce neutralization by most of a large panel of potent monoclonal antibodies and antibodies under commercial development. Omicron S has structural changes from earlier viruses, combining mutations conferring tight binding to ACE2 to unleash evolution driven by immune escape, leading to a large number of mutations in the ACE2 binding site which rebalance receptor affinity to that of early pandemic viruses.

Molecular characterization of polymorphisms among Pseudomonas aeruginosa strains isolated from burn patients' wounds.

Pseudomonas aeruginosa is one of the most common reasons for nosocomial infections. Given the high morbidity and mortality, as well as the cost of management, particularly in developing countries, burn injuries are considered important health concerns. Owing to the increased rate of resistance against antibiotics, this study aimed to isolate Pseudomonas aeruginosa strains from burn patient's wounds by analyzing antibiotic susceptibility and genetic profiling. In this regard, we explored the relationship between the nucleotide sequence and antibiotic susceptibility. In this cross-sectional study, 107 isolates of P. aeruginosa were collected from a major burn center in Tehran, Iran. The isolates were characterized with standard biochemical tests and examined by applying the Disk Diffusion method to find the patterns of sensitivity, and their genetic relationship was revealed by RAPD-PCR method. According to the antibiogram results, most of the isolates were resistant to 3 or more antibiotics tested and the most sensitivity was related to the Colistin antibiotic. RAPD-PCR method revealed a high polymorphism among P. aeruginosa isolates in Tehran. There was no significant association between the genotype groups and antibiotic susceptibility profiles. We evaluated the pattern of resistance to pathogenic organisms and identified multi-drug resistant organisms. Currently, Colistin antibiotic is the most suitable treatment option for burned patients. RAPD-PCR is a genotyping method with high efficiency for typing and categorizing different isolates of MDR-P. aeruginosa.

Unilateral Macular Choroidal Neovascularization; a Rare Manifestation in Chronic Myelogenous Leukemia.

PURPOSE: To report a case of chronic myelogenous leukemia (CML) treatment with imatinib mesylate in the remission phase who developed unilateral macular choroidal neovascularization (CNV). METHODS: A 45-year-old male marketer with a 5-year history of CML treated with imatinib mesylate presented with 2 months history of progressive vision loss and metamorphopsia in the right eye. RESULTS: Fundus examination of the right eye revealed grey-white elevated retinal lesion with indistinct borders in the macula and retinal telangiectasia in the temporal macula. Fluorescein angiography (FA) and optical coherence tomography angiography (OCTA) confirmed the presence of CNV in the right eye. After treatment with anti-vascular endothelial growth factor (anti-VEGF), macular CNV regressed significantly. CONCLUSION: Macular CNV must be kept in mind as a rare ophthalmic manifestation of patients with CML under treatment with imatinib even in the remission phase.

Short prism adaptation test in patients with acquired nonaccommodative esotropia; clinical findings and surgical outcome.

PURPOSE: To evaluate the surgical outcomes in patients with acquired nonaccommodative esotropia operated on based on a short prism adaptation test (PAT) and to determine the subgroup of patients most responsive to PAT. METHODS: In this prospective interventional cases series, patients with acquired nonaccommodative esotropia were enrolled. Patients wore Fresnel trial lenses based on the results of alternate prism-cover testing. With the Fresnel prism in place, alignment was measured after 20 minutes. If deviation increased, the power of prism was increased to neutralize this angle. The test was repeated every 20 minutes to achieve motor stability. Patients were classified as either prism responders (if the angle of deviation increased >10Δ compared to the entry angle) or prism nonresponders. All patients underwent bilateral medial rectus muscle recession. Prism responders underwent surgical correction based on the enhanced angle. RESULTS: Of the 28 subjects enrolled, 14 (50%) were prism responders and 14 (50%) were classified as prism nonresponders. After 6 months, 100% of prism responders and 92.9% of nonresponders were aligned within 8Δ of orthotropia at distance and near fixation. None of the patients with an entry angle of >30Δ were prism responders. CONCLUSIONS: In our study cohort, a short PAT with an endpoint of motor stability in patients with acquired nonaccommodative esotropia was associated with a good surgical outcome and a low rate of over- and undercorrection. PAT may be unnecessary for patients with an angle of deviation of >30Δ.

Consequences of inadvertent intravitreal Mitomycin C injection.

BACKGROUND: Mitomycin C (MMC) as an alkylating agent is miscellaneous an antineoplastic, antibiotic and ophthalmic agent. Here we aim to report a case of inadvertent intravitreal MMC injection instead of Avastin in case of diabetic macular edema. CASE PRESENTATION: A 53 years old woman was planned to receive intravitreal Avastin injection, but accidentally, 0.05 ml of MMC 0.2% was injected. Best corrected visual acuity (BCVA) was 20/160 before injection. After 2 days, patient was referred to a tertiary referral eye center. BCVA was hand motion at presentation. Intraocular pressure was 4 mmHg. In slit lamp exams, conjunctival injection, corneal edema, Descemet fold, anterior chamber and anterior vitreous cells were presented. Pars plana vitrectomy with peripheral vitreous shaving and silicone oil tamponade was performed. Electroretinography showed undetectable responses. Ultrasound biomicroscopy showed ciliary body shortening and detachment. Optical coherent tomography showed diffuse retinal edema the day after surgery, subretinal fluid pockets in 2 weeks, and atrophy with undetectable and intertwined layers 2 months later. Gradually, like the retina, iris became atrophic and pigments were dispersed diffusely over the lens and endothelium. CONCLUSION: MMC is showed to be severely toxic to intraocular tissues. In our case, iris and ciliary body became atrophic. Ciliary body detachment induced hypotony. Moreover, MMC induces retinal necrosis and atrophy. Visual outcome is profoundly poor.

Plant-made polio type 3 stabilized VLPs-a candidate synthetic polio vaccine.

Poliovirus (PV) is the causative agent of poliomyelitis, a crippling human disease known since antiquity. PV occurs in two distinct antigenic forms, D and C, of which only the D form elicits a robust neutralizing response. Developing a synthetically produced stabilized virus-like particle (sVLP)-based vaccine with D antigenicity, without the drawbacks of current vaccines, will be a major step towards the final eradication of poliovirus. Such a sVLP would retain the native antigenic conformation and the repetitive structure of the original virus particle, but lack infectious genomic material. In this study, we report the production of synthetically stabilized PV VLPs in plants. Mice carrying the gene for the human PV receptor are protected from wild-type PV when immunized with the plant-made PV sVLPs. Structural analysis of the stabilized mutant at 3.6 Å resolution by cryo-electron microscopy and single-particle reconstruction reveals a structure almost indistinguishable from wild-type PV3.Despite the success of current vaccination against poliomyelitis, safe, cheap and effective vaccines remain sought for continuing eradication effort. Here the authors use plants to express stabilized virus-like particles of type 3 poliovirus that can induce a protective immune response in mice transgenic for the human poliovirus receptor.

Serum IL-33 Is Elevated in Children with Asthma and Is Associated with Disease Severity.

BACKGROUND: The role of IL-33, a member of the IL-1 family, in airway hyperresponsiveness and asthma has still to be fully understood. OBJECTIVES: This study is aimed at investigating serum IL-33 in children with asthma and its association with asthma severity. METHODS: This age- and sex-matched case-control study comprised 61 children with asthma and 63 healthy controls. The mean age of the participants was 9.21 years (range: 6-14). Serum IL-33 was measured using ELISA and was compared between children with asthma and controls. In addition, the association of serum IL-33 with asthma severity was investigated. RESULTS: The level of serum IL-33 was significantly higher in children with asthma than in controls (15.17 ± 32.3 vs. 0.61 ± 2.16 pg/ml; p = 0.028). It was significantly increased proportionately to asthma severity, namely 9.92 ± 30.26 pg/ml in children with mild asthma, 13.68 ± 29.27 pg/ml in children with moderate asthma and 31.92 ± 41.45 pg/ml in children with severe asthma (p = 0.026). CONCLUSION: Serum IL-33 is increased in children with asthma and is associated with disease severity.

Anterior and posterior corneal curvature: normal values in healthy Iranian population obtained with the Orbscan II.

The objective of study was to determine the normative values of anterior and posterior best fit sphere (A-BFS and P-BFS) measured with Orbscan II Topography System. In this cross-sectional study, patients (age range: 18-40 years) referred to the Khatam Eye Hospital (Mashhad, Iran) were put in an observational cross-sectional study. The A-BFS and P-BFS were measured with the Orbscan II. The differences between genders, between right and left eyes, and age-related changes were evaluated. A total of 977 healthy participants consisted of 614 female and 363 male subjects aged 18-35 years participated. The average A-BFS in our study population was recorded as 43.060 ± 1.541 D (median: 43.00 D, mode: 43.10 D, range: 38.80-55.80 D). The average P-BFS in our study population was recorded as 52.702 ± 2.190 D (median: 52.60 D, mode: 53.10 D range: 46.9-62.20 D). The A-BFS and P-BFS were respectively 42.753 ± 1.629 and 52.327 ± 2.376 D in males and 43.242 ± 1.457 and 52.924 ± 2.041 D in females, which were statistically different between the genders (P < 0.001). However, A-BFS and P-BFS were not statistically different between right and left eyes (P = 0.649 and P = 0.688 respectively). In addition, A-BFS and P-BFS were not correlated with the age (r = 0.038, P = 0.096 and r = -0.142, P = 0.178 respectively). Considering 95 % confidence interval, A-BFS less than 43.13 D and greater than 42.99 D and P-BFS less than 52.80 D and greater than 52.60 D would be considered abnormal. Detailed description and analysis of A-BFS and P-BFS with Orbscan demonstrated that the obtained average value of BFS were higher in male than female and did not change with increasing age.