Mesenchymal Stem/Stromal Cells: DEVELOPMENT OF A GMP BANKING PROCESS FOR UMBILICAL CORD MESENCHYMAL STROMAL CELLS (UC-MSCS) AND USE OF UC-MSC IN CHARACTERISATION ASSAYS, FUNCTIONAL ASSAYS AND GENE EDITING STUDIES

Background & Aim: The pro-angiogenic, immunoregulatory and anti- inflammatory properties of MSCs are being exploited for the development of cellular therapies, including the treatment of graft versus host disease (GvHD), inflammatory bowel disease and COVID-19. SNBTS have developed a GMP process to bank umbilical cord MSCs (UC-MSCs) whereby we can reliably bank 100 vials of 10 million P2 UC-MSCs per cord. Each of these vials can be extensively expanded and stored for specific applications. The ultimate aim of the bank is for off-the-shelf clinical use, e.g., in GvHD or as an adjuvant therapy in Islet transplantations. Methods, Results & Conclusion(s): During process development, different basal media and supplements were screened for proliferation and MSC marker expression. Cells grown in promising media combinations were then tested for tri-lineage differentiation (identity), their chemokine/cytokine expression and T-cell inhibition (function) assessed. Medium selected for further GMP development and scale up was ultimately determined by all round performance and regulatory compliance. GMP-like UC-MSCs were shown to have immune-modulatory activity in T-cell proliferation assays at 4:1 or 16:1 ratios. Co-culture of UC-MSCs and freshly isolated leukocytes, +/- the immune activating agent LPS, show a dose dependent survival effect on leukocytes. In particular, neutrophils, which are normally very short lived in vitro demonstrated increased viability when co-cultured with UCMSCs. The survival effect was partially reproduced when UC-MSC were replaced with conditioned medium or cell lysate indicating the involvement of soluble factors. This improved neutrophil survival also correlates with results from leukocyte migration studies that demonstrate neutrophils to be the main cell type attracted to MSCs in in vitro and in vivo. Genetic modification of UC-MSC may improve their therapeutic potential. We have tested gene editing by CRISPR/Cas9 technology in primary UC-MSCS. The CXCL8 gene, highly expressed in UC-MSC, was targeted in isolates from several different donors with editing efficiencies of 78-96% observed. This translated to significant knockdown of CXCL8 protein levels in resting cells, however after stimulation levels of CXCL8 were found to be very similar in edited and non-edited UC-MSCs. This observation requires further study, but overall the results show the potential to generate future banks of primary UC-MSCS with genetically enhanced pro-angiogenic, immunoregulatory and/or anti-inflammatory activities.Copyright © 2023 International Society for Cell & Gene Therapy

2C5-surface modified nanocarriers targeting neutrophil extracellular traps

Background: Neutrophil extracellular traps (NETs) are composed of processed chromatin bound to granular and selected cytoplasmic proteins and released by neutrophils. NETs consist of smooth filaments composed of stacked nucleosomes. Fully hydrated NETs have a cloud-like appearance and occupy a space 10-15-fold larger than the volume of the cells they originate from. DNases are the enzymes that cleave extracellular DNA including NETs. Together with their protective role in microbial infections, NETs are involved in multiple pathological processes and represent key events in a variety of pathologies including cancer, autoimmunity, and cardiovascular disease. Sites of NETs concentration are dangerous for the host if the process of NETs formation becomes chronic or the mechanism of NETs removal does not work. NETosis has been linked to the development of periodontitis, cystic fibrosis, type 2 diabetes, COVID-19 or rheumatoid arthritis as well as cancer progression. Purpose(s): Thus, the destruction of NETs is of primary significance in many pathologies. In our approach, we are focusing on mimicking one of the natural mechanisms of destroying excessive NETs by delivering deoxyribonuclease I to the specific site of pathological NETs accumulation by modifying the nanoparticles using an anti-nucleosome monoclonal antibody (2C5). The antibody is specific to nucleosomes and can recognize histones in NETs. DNase I is U.S. Food and Drug Administration (FDA)-approved active component and is commonly used in therapeutic methods of modern medicine for cystic fibrosis to clear extracellular DNA fibers in the lungs and systemic lupus erythematosus. Recent findings have also shown the effectiveness of DNase I in the digestion of NETs. However, the low serum stability and fast deactivation by environmental stimuli have been considered as the limiting factors for clinical applications of DNase I, which can be overcome by its targeted specific delivery in pharmaceutical nanocarriers. Method(s): In this study, we generate NETs in vitro using human neutrophils and HL-60 cells differentiated into granulocyte-like cells. We used interleukin-8, lipopolysaccharide from E.Coli (LPS), phorbol myristate acetate (PMA), and calcium ionophore A23187 (CI) to generate the NETs. We confirmed the specificity of 2C5 toward NETs by ELISA, which showed that it binds to NETs with the specificity like that for purified nucleohistone substrate. We further utilized that feature to create two delivery systems (liposomes and micelles) for DNAse I enzyme to destroy NETs, which was confirmed by staining NETs with SYTOX Green dye and followed by flow cytometric measurements and microscopic images. Conclusion(s): Our results suggest that 2C5 could be used to identify and visualize NETs and serve as a ligand for NET-targeted diagnostics and therapies. Also, we proved that our carrier can successfully deliver DNase to NETs to provide their degradation.

SARS-CoV-2 VARIANTS-DEPENDENT INFLAMMASOME ACTIVATION

Background: Innate immunity is the first line of defense in response to pathogens, which acts locally and also leads the stimulation of adaptive immunity through at least with IL-1beta secretion. It has been shown that SARSCoV- 2 infection triggered the NLRP-3 inflammasome activation and the IL-1beta secretion. The aim of this study was to analyze and compare the level of IL-1beta secretion that is one of the most important innate immunity cytokines, in monocyte-like cells infected with 6 different variants of the SARS-CoV-2. Method(s): Six SARS-CoV-2 variants (historical (B.1, D614G), Alpha, Beta, Gamma, Delta and Omicron BA.1) were isolated from COVID-19 hospitalized patients. Viral stocks were obtained by inoculation in Vero and Vero-TRMPSS2 cells. THP-1 monocyte-like cells were cultured with RPMI-hepes 10% FBS-0.05 mM 2-mercaptoethanol. A total of 5 x 104 of THP-1 cells was plated per well in 96-wells plate and differentiated with 10nM of PMA for 24h. Differenciated- THP-1 were first primed with LPS 1mug/ml for 2h and infected with different SARS-CoV-2 variants with a MOI 0.1. IL-1beta was measured by luminescence in the supernatant after 24 h of infection. Result(s): We analyzed and compared IL-1beta secretion between SARS-CoV-2 virus 6 sublineages after infection of monocytes like THP-1. We observed that THP-1 cells infected with SARS-CoV-2 variants presented a significantly higher IL-1beta secretion than non-infected cells. Moreover, some SARS-CoV-2 variants led to a stronger IL-1beta secretion, and particularly we observed a significantly higher level of IL-1beta cells infected with Omicron BA.1 sublineage compared to other variants. Indeed, Omicron BA.1 infected cells presented the higher IL-1beta secretion (median 385.7 pg/ml IQR[302.6-426.3]) follows by the Delta variants and the historical variants (median 303.6 [266.3-391.9] and 281.9 [207.2-410], respectively). Alpha, Beta and Gamma variants presented the lowest IL-1beta secretion (median 228.1 [192.5-276.4], 219.1 [185.1-354.2] and 211 [149.8- 228.8]). Conclusion(s): We observed the inflammasome activation for the 6 SARS-CoV-2 sublineages with a variation in level of IL-1beta secretion. Indeed, our results suggested that Omicron BA.1 was more recognized by the innate immune cells than other SARS-CoV-2, which could in part, with its upper respiratory tract tropism, possibly explain its less clinical virulence. Taking together, these results suggest that the innate immunity response and precisely, IL-1beta secretion pathways were activated in a SARS-CoV-2 variants-dependent manner.

Hyperglycemia and Hypoglycemia Contributions to Acute Respiratory Distress Syndrome

Purpose of Study Non-diabetic COVID-19 patients with elevated admission fasting blood glucose levels ('hyperglycemia') inexplicably have an increased 28 day mortality and higher inhospital complications including the Acute Respiratory Distress Syndrome (ARDS) but potentially contributing blood glucose changes during ARDS development were not reported (Wang S et al: Diabetologia 2020). Our goal was to determine blood glucose alterations before and during acute lung injury development in a rat model used to study ARDS. Methods Used We sequentially evaluated blood glucose levels for 24 hours and lung lavage protein levels (lung permeability) and lung lavage neutrophil numbers (lung inflammation) at 24 hours to assess acute lung injury ('ARDS') in young (~3 month) and old (~12 month) control and a novel strain of hyperoxia surviving 'resistant' rats before and after administering high and low insulin doses and before and after interleukin- 1/lipopolysaccharide (IL-1/LPS) insufflation. Summary of Results Glucose levels increase rapidly and sequentially in young control, but not young resistant, rats peaking ~2 hours after insufflation. Glucose levels also increase in old control and old resistant rats after insufflation compared to young control and young resistant rats after insufflation. The pattern of glucose levels at 2 hours after insufflation resembles lung lavage proteins and neutrophils at 24 h after insufflation (table 1). Administering high insulin (High In) doses decreases glucose levels ('hypoglycemia') and worsens ARDS while administering low insulin (Low In) doses correct glucose levels and improve ARDS. Conclusions Hyperglycemia develops in both young and old rats developing ARDS and high or low glucose levels parallel worse acute lung inflammation and acute lung injury ('ARDS'). Controlling glucose judiciously with insulin may be beneficial in combatting ARDS caused by SARS-CoV-2 infection and other insults.

Increased Gut Permeability and Oxidized Lipids in Pasc

Background: Post-acute sequelae of COVID-19 (PASC) is marked by persistent or newly developing symptoms beyond 4 weeks of infection. Investigating gut integrity, oxidized lipids and inflammatory markers is important for understanding PASC pathogenesis. Method(s): A cross-sectional study including COVID+ with PASC, COVID+ without PASC, and COVID- participants. We measured plasma markers by enzyme-linked immunosorbent assay to assess gut-barrier integrity: zonulin for intestinal permeability, lipopolysaccharide-binding protein (LBP) for microbial translocation, and fatty acid binding protein I-FABP for intestinal integrity, and to assess inflammation: high-sensitivity C-reactive protein (hsCRP) and oxidized low-density lipoprotein (Ox-LDL) assays. Result(s): 415 participants were enrolled in our study. 62.17% (n=258) were COVID- and 20.48% (n=85) had PASC. COVID- participants had lower age (43.68+/-13.69 vs. 46.45+/-13.45 years;p=0.04), lower BMI (27.91+/-6.05 vs. 31.28+/-9.03;p< .0001), 39.15% (n=101) were female sex [vs. 54.14% (n=85);p=0.003], and 41.86% (n=108) were non-white race [vs. 32.48% (n=51);p=0.06] compared to COVID+. Zonulin (p< .0001), and Ox-LDL (p< .0001) were associated with COVID and PASC status. The mean Zonulin among COVID- was 3755960.41+/-2541177.0 ng/mL, 3912178.91+/-2649882.95 ng/mL among COVID+ without PASC, and the highest (5899694.16+/-4110456.4 ng/ mL) among PASC. The mean Ox-LDL was lowest (51845.21+/-24328.46 U/L) among COVID-, 60530.09+/-26497.47 U/L among COVID+ without PASC, and 81917.21+/-32148.59 U/L among PASC. The estimated mean difference in Zonulin among PASC compared to COVID- was 2143734+/-368522 ng/mL (p< .0001) and compared to COVID+ without PASC was 1987515+/-471965 ng/mL (p< .0001). The estimated mean difference in Ox-LDL among PASC compared to COVID- was 30072+/-3311.02 U/L (p<.0001) and compared to COVID+ without PASC was 21387+/-4240.41 (p<.0001). Zonulin was positively associated with hs-CRP and Ox-LDL. For every unit increase in Zonulin we would expect hsCRP to increase by 86.14+/-15.09/100000 ng/mL (p<.0001) and OX-LDL to increase by 22.2+/-4.05/10000 ng/mL (p<.0001). Conclusion(s): PASC is associated with increased gut permeability, which in turn is associated with oxidized LDL and hsCRP. (Figure Presented).

AUTOPHAGY AND Acyl-CoA-BINDING PROTEIN INFLUENCE COVID-19 SEVERITY

Background: Autophagy, a cytosolic-structure degradation pathway, allows production of IL21 by CD4 T-cells and efficient cytolytic responses by CD8 T-cells. Autophagy is in part regulated by acyl-CoA-binding protein (ACBP) which has two functions. Intracellular ACBP favors autophagy, whereas secreted extracellular ACBP inhibits autophagy. Herein, we assessed whether autophagy and the ACBP pathway were associated with COVID-19 severity. Method(s): Through the BQC-19 Quebec biobank, somalogic proteomic analysis was performed on 5200 proteins in plasma samples collected between March 2020 and December 2021. Plasma from 903 patients (all data available) during the acute phase of COVID-19 were assessed. COVID-19 severity was stratified using WHO criteria. In vitro, ACBP intracellular levels, autophagy levels (LC3II) and IL21 production were assessed by flow in PBMCs after a 24h stimulation with IL6, phorbol myristate acetate (PMA)+ionomycin or lipopolysaccharide (LPS). Plasma levels of anti-SARS-CoV-2 (full spike protein or RBD) IgG were assessed by ELISA. Result(s): Median age of the cohort was 62 yo, 48% were female, 55% had comorbidities (see table). Increasing plasma levels of ACBP were found with severity (mild, moderate, severe and fatal groups having 5.3, 7.3, 9.5 and 10.6 RFU/50muL of plasma, respectively, p< 0.001 for all comparisons). Patients with comorbidities had higher plasma ACBP levels (7.4 vs 6.4 RFU/50muL, p< 0.001). Plasma ACBP levels were higher during the delta and omicron-variant periods (8.4 vs 6.8 RFU/50muL;p< 0.001). Plasma ACBP levels correlated with LC3II levels (r=0.51, P< 0.001) and IL6 (r=0.41, p< 0.001), but neither with markers IL1beta nor IL8. ACBP levels negatively correlated with IL21 levels (r=-0.27, p< 0.001), independently of age, sex, and severity. ACBP levels were not associated with levels of anti-SARS-CoV-2 IgG levels. In vitro, IL6 stimulation of healthy control PBMC induced extracellular ACBP release. Moreover, adding recombinant ACBP: 1) reduced autophagy in lymphocytes and monocytes upon polyclonal stimulation with PMA/ionomycin or LPS;2) reduced intracellular production of IL21 in T-cells after PMA/ ionomycin stimulation. Conclusion(s): Plasma ACBP levels were inversely linked with IL21 levels, suggesting that autophagy and IL21 allow control of SARS-CoV-2 infection, independently of the level of SARS-CoV-2 antibody secretion. ACBP is a targetable autophagy checkpoint and its extracellular inhibition may improve SARS-CoV-2 immune control. (Table Presented).

Isolation and Characterization of Protein Complexes of Overexpressed Human Serum Amyloid A from Cytokines-Induced Hepg2 Cells

Serum Amyloid A (SAA) is an apolipoprotein found in the serum of many vertebrate species and is associated with the acute-phase reaction in the body with expression levels reaching up to a 1000-fold increase. The loss of its alpha-helix conformation during its expression peak is directly linked to secondary amyloidosis. Recent studies have been suggested to play a role in cholesterol and HDL metabolism, retinol transport and tumor pathogenesis. Moreover, high SAA concentration in blood have been correlated with severe symptoms or death in patients with COVID-19. However, how this protein is involved in so many diseases is uncertain or not completely understood. Therefore, the purpose of this research is to determine which protein-protein interactions with SAA occur in human cells, and to predict its biochemical role based on new discovered complexes. Two major isoforms overexpressed during an acutephase reaction, human SAA1 and SAA2, are the focus of this study. Both are primarily produced in hepatocytes. HepG2 cells were cultured and induced with interleukin-1b, interleukin-6, LPS and retinol. Protein complexes associated with SAA will be isolated through a co-Immunoprecipitation technique, resolved by SDS-PAGE, and characterized by mass spectrometry. Our hypothesis focus on those protein complexes with SAA to explain how this protein lead other undiscovered metabolic pathways involved in both cellular and survival regulation. Special thanks to The Science and Technology Competency & Education Core (Stce) for Undergraduate and Graduate Junior Research Associates Working Program from the Puerto Rico IDeA Network Biomedical Research Excellence for funding part of this research.Copyright © 2023 The American Society for Biochemistry and Molecular Biology, Inc.

7th Turkey in vitro Diagnostics (IVD) Symposium

The proceedings contain 75 papers. The topics discussed include: development of different product groups in the cleaning industry with synthesized nanosilver;investigation of the antimetastatic potential of thymbra spicata in human breast adenocarcinoma cells combined with standard chemotherapy;the effect of toll-interancing protein on inflammatory status of hepatocellular carcinoma cell line;surgery and inflammation: surgical inflammation;biochemistry of inflammation;its mediators and activities;pathophysiology of inflammation;classic and new biomarkers of inflammation;thymol reduces the lipopolysaccharide-induced acute kidney inflammation by modulating lysosomal stress;metabolic shift of the kynurenine pathway in inflammatory conditions;and evaluation of HBA1C level in patients with COVID-19.

Obesity and its impact on endotoxemia and systemic inflammation in acute SARS-CoV- 2 infection

Background: Given the coexistence of the COVID-19 pandemic and the worldwide epidemic of obesity, which in some Western countries affects up to 40% of the population, it is crucial today to understand the mechanisms involved in the worsening course of the new SARS-CoV- 2 coronavirus infection in obese patients. So-called "metabolic endotoxemia" associated with excess body weight and obesity may be one of the most important factors potentiating the effect of SARS-CoV- 2 virus influencing the prognosis of the disease. Method(s): 55 patients with SARS-CoV- 2 infection of moderate severity (patients with normal body mass index (BMI) -10;patients with BMI > 25 kg/m2 -19 and patients with BMI > 30 kg/m2 -26) and 20 controls were studied. Lipopolysaccharide binding protein (LBP), sCD14-ST and C-reactive protein (CRP) levels were measured by ELISA in plasma of patients taken on the day of admission to the hospital. Result(s): The plasma LBP (mug/ml) level was significantly greater in the group of patients with BMI > 30 kg/m2 (Me [Q1;Q3]) -52.5 [31.16;75.0], than in groups with BMI > 25 kg/m2 -48.3 [10.6;60] (p < 0.05), normal BMI -33.5 [8.3;54.8] (p < 0.01) and control group -18.6 [15.2;20.5] (p < 0.001). The plasma sCD14-ST (pg/ml) levels in the 2nd (2400.0 [1200.0;2900.0]) and 3rd (2100.0 [1290.0;1340.0]) group did not differ significantly (p > 0.05), but was significantly greater than in group with normal BMI -1310.0 [720.0;2325] (p < 0.05) and the control group -218.0 [80.0;292.0] (p < 0.01). The plasma CRP (mg/L) levels in the 1st (31.1 [9.3;51.0]) and 2nd (31.8 [15.7;57.3]) group did not differ significantly (p > 0.05), but was significantly less than in the group with BMI > 30 kg/m2 -40.5 [26.6;60.0] (p < 0.05) and the control group -0.5 [0.3;0.9] (p < 0.001). Conclusion(s): The phenomenon of "metabolic endotoxemia" in overweight and obese patients may contribute to the formation of high systemic inflammation in SARS-CoV- 2 virus-associated endothelial dysfunction and thrombotic microangiopathy.

Immunisation with purified Coxiella burnetii phase I lipopolysaccharide confers partial protection in mice independently of co-administered adenovirus vectored vaccines.

Q fever is a highly infectious zoonosis caused by the Gram-negative bacterium Coxiella burnetii. The worldwide distribution of Q fever suggests a need for vaccines that are more efficacious, affordable, and does not induce severe adverse reactions in vaccine recipients with pre-existing immunity against Q fever. Potential Q fever vaccine antigens include lipopolysaccharide (LPS) and several C. burnetii surface proteins. Antibodies elicited by purified C. burnetii lipopolysaccharide (LPS) correlate with protection against Q fever, while antigens encoded by adenoviral vectored vaccines can induce cellular immune responses which aid clearing of intracellular pathogens. In the present study, the immunogenicity and the protection induced by adenoviral vectored constructs formulated with the addition of LPS were assessed. Multiple vaccine constructs encoding single or fusion antigens from C. burnetii were synthesised. The adenoviral vectored vaccine constructs alone elicited strong cellular immunity, but this response was not correlative with protection in mice. However, vaccination with LPS was significantly associated with lower weight loss post-bacterial challenge independent of co-administration with adenoviral vaccine constructs, supporting further vaccine development based on LPS.

Liquiritin exhibits anti-acute lung injury activities through suppressing the JNK/Nur77/c-Jun pathway.

BACKGROUND: Licorice (Glycyrrhiza uralensis Fisch.), a well-known traditional medicine, is traditionally used for the treatment of respiratory disorders, such as cough, sore throat, asthma and bronchitis. We aim to investigate the effects of liquiritin (LQ), the main bioactive compound in licorice against acute lung injury (ALI) and explore the potential mechanism. METHODS: Lipopolysaccharide (LPS) was used to induce inflammation in RAW264.7 cells and zebrafish. Intratracheal instillation of 3 mg/kg of LPS was used for induction an ALI mice model. The concentrations of IL-6 and TNF-α were tested using the enzyme linked immunosorbent assay. Western blot analysis was used to detect the expression of JNK/Nur77/c-Jun related proteins. Protein levels in bronchoalveolar lavage fluid (BALF) was measured by BCA protein assay. The effect of JNK on Nur77 transcriptional activity was determined by luciferase reporter assay, while electrophoretic mobility shift assay was used to examine the c-Jun DNA binding activity. RESULTS: LQ has significant anti-inflammatory effects in zebrafish and RAW264.7 cells. LQ inhibited the expression levels of p-JNK (Thr183/Tyr185), p-Nur77 (Ser351) and p-c-Jun (Ser63), while elevated the Nur77 expression level. Inhibition of JNK by a specific inhibitor or small interfering RNA enhanced the regulatory effect of LQ on Nur77/c-Jun, while JNK agonist abrogated LQ-mediated effects. Moreover, Nur77-luciferase reporter activity was suppressed after JNK overexpression. The effects of LQ on the expression level of c-Jun and the binding activity of c-Jun with DNA were attenuated after Nur77 siRNA treatment. LQ significantly ameliorated LPS-induced ALI with the reduction of lung water content and BALF protein content, the downregulation of TNF-α and IL-6 levels in lung BALF and the suppression of JNK/Nur77/c-Jun signaling, which can be reversed by a specific JNK agonist. CONCLUSION: Our results indicated that LQ exerts significant protective effects against LPS-induced inflammation both in vivo and in vitro via suppressing the activation of JNK, and consequently inhibiting the Nur77/c-Jun signaling pathway. Our study suggests that LQ may be a potential therapeutic candidate for ALI and inflammatory disorders.

Biomolecules of the Horseshoe Crab's Hemolymph: Components of an Ancient Defensive Mechanism and Its Impact on the Pharmaceutical and Biomedical Industry

Without adaptive immunity, invertebrates have evolved innate immune systems that react to antigens on the surfaces of pathogens. These defense mechanisms are included in horseshoe crab hemocytes' cellular responses to pathogens. Secretory granules, large (L) and small (S), are found on hemocytes. Once the invasion of pathogens is present, these granules release their contents through exocytosis. Recent data in biochemistry and immunology on the granular constituents of granule-specific proteins are stored in large and small granules which are involved in the cell-mediated immune response. L-granules contain most clotting proteins, which are necessary for hemolymph coagulation. They also include tachylectins;protease inhibitors, such as cystatin and serpins;and anti-lipopolysaccharide (LPS) factors, which bind to LPS and agglutinate bacteria. Big defensin, tachycitin, tachystatin, and tachyplesins are some of the essential cysteine-rich proteins in S-granules. These granules also contain tachycitin and tachystatins, which can agglutinate bacteria. These proteins in granules and hemolymph act synergistically to fight infections. These biomolecules are antimicrobial and antibacterial, enabling them to be drug resistant. This review is aimed at explaining the biomolecules identified in the horseshoe crab's hemolymph and their application scopes in the pharmaceutical and biotechnology sectors.Copyright © 2022 Md. Ashrafuzzaman et al.

Landscape Analysis of Quercetin: A Potential Candidate Against SARS-CoV-2

Fruit, vegetables, and green tea contain quercetin (a flavonoid). Some of the diet's most signifi-cant sources of quercetin are apples, onions, tomatoes, broccoli, and green tea. Antioxidant, anticancer, anti-inflammatory, antimicrobial, antibacterial, and anti-viral effects have been studied of quercetin. The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus, ribonucleic acid (RNA) polymer-ase, and other essential viral life-cycle enzymes are all prevented from entering the body by quercetin. Despite extensive in vitro and in vivo investigations on the immune-modulating effects of quercetin and vitamin C treatment. 3-methyl-quercetin has been shown to bind to essential proteins necessary to convert minus-strand RNA into positive-strand RNAs, preventing the replication of viral RNA in the cytoplasm. Quercetin has been identified as a potential SARS-CoV-2 3C-like protease (3CLpro) suppressor in recent molecular docking studies and in silico assessment of herbal medicines. It has been demonstrated that quercetin increases the expression of heme oxygenase-1 through the nuclear factor erythroid-related factor 2 (Nrf2) signal network. Inhibition of heme oxygenase-1 may increase bilirubin synthesis, an endoge-nous antioxidant that defends cells. When human gingival fibroblast (HGF) cells were exposed to lipo-polysaccharide (LPS), inflammatory cytokine production was inhibited. The magnesium (Mg+2) cation complexation improves quercetin free radical scavenging capacity, preventing oxidant loss and cell death. The main objective of this paper is to provide an overview of the pharmacological effects of quercetin, its protective role against SARS-CoV-2 infection, and any potential molecular processes.Copyright © 2022 Bentham Science Publishers.

Severe lymphocyte dysfunction and impaired cellular immune response as a consequence of COVID-19

Introduction: A correct diagnosis of long-term complications in COVID-19 convalescents is of great importance for their therapeutic management. Aim(s): To identify long-term post-COVID-19 damages related to lymphocytes T to search prevention and treatments in future. Material(s) and Method(s): Data from 10 healthy volunteers, 23 patients (moderate/severe) COVID-19 were analysed. Responses of lymphocytes to LPS, ConA, CD3/CD28 mitogens and spike protein were measured in all groups during acute phase, 3- and 6-months post-hospitalization. Main lymphocyte T subpopulations (CD4, CD8) and CD25 expression on the lymphocyte subpopulations were also examined. Result(s): 6 of 13 severe patients were ventilated mechanically. The remaining 6 patients improved after high-flow nasal oxygen therapy and were discharged with normalized respiratory functions, the same as the mild/moderate COVID-19 group. We found that the decrease in total lymphocytes is equally due to the decrease in CD4 and CD8 cells. These changes persist in moderate and severely ill groups over 3 months post-COVID-19. In the case of CD4 lymphocytes, the changes concerned both naive (CD4+/CD25-) and activated (CD4+/CD25+) cells. A significant decrease in the CD8 cells was also observed, but only for the absolute number of naive CD8 lymphocytes (CD8+/CD25-). During the acute COVID-19 a significant impaired responses to ConA and CD3/CD28 were found. No difference in spike protein response was noticed. Conclusion(s): Long-term reductions (3- and 6-months) in the total count of lymphocytes in subpopulations and proliferative responses to mitogens suggest a severe impairment of the cellular immune response.

Attenuated effects of rivastigmine in induced cytokine storm in mice

Background: A cytokine storm is a serious clinical condition that complicates infectious diseases, for example, coronavirus disease 2019 (COVID-19), and non-infectious diseases such as autoimmune diseases and cancer and may often lead to death. The patients who are affected by the cytokine storm are almost always severe/critical and at risk for acute respiratory distress syndrome or eventually death. Pro-inflammatory cytokines such as interleukin 6 (IL-6), IL-1 beta, and tumor necrosis factor alpha (TNF-alpha) have been repeatedly shown to be related to the COVID-19 disease severity and mortality. In this study, our objective was to evaluate the attenuated effect of rivastigmine (RA) in a cytokine storm in Swiss Albino mice in which the cytokine storm was induced by lipopolysaccharide (LPS) and to explore their effects on IL-1 beta, IL-6, and TNF-alpha levels. Method(s): This study was carried with 60 male Swiss albino mice that were divided equally and randomly into six groups as follows: *Group AH: Apparently healthy control group which received no induction, not treated. *Group LPS: Induced using LPS at 5 mg/kg and no treatment administered. *Group DMSO: Induced and treated with 1% dimethyl sulfoxide (DMSO). *Group RA: Induced and treated with 0.5 mg/kg RA. *Group MPA: Induced and treated with 50 mg/kg methylprednisolone (MPA). *Group RMPA: Induced and treated with 0.25 mg/kg rivastigmine and 25 mg/kg of methylprednisolone. All the mice were treated with drugs or vehicles for three consecutive days before LPS induction. The mice were then injected with LPS intraperitoneally at a dosage of 5 mg/kg for systematic inflammatory stimulation. After 48 hours of LPS induction, all the mice were euthanized by light anesthesia with chloroform, and blood was collected for the quantitative determination of IL-1beta, IL-6, and TNF-alpha levels using the enzyme-linked immunosorbent assay (ELISA) technique. Result(s): Administration of LPS to Swiss albino mice caused a significant elevation of IL-1beta, IL-6, and TNF-alpha levels than in the healthy control group. Significant reduction of these parameters were observed in the RA and MPA groups when compared with those in the non-treated group. Conclusion(s): RA was found to be effective in attenuating the induced cytokine storm by suppressing IL-1beta, IL-6, and TNF-alpha levels, and the results with RA were comparable to that of MPA. A combination of half-doses of both RA and MPA administered together shows no obvious advantage when compared with that of each of them alone.Copyright © 2022 Mansoor, Raghif, licensee HBKU Press

Development of thermosensitive hydrogel of Amphotericin-B and Lactoferrin combination-loaded PLGA-PEG-PEI nanoparticles for potential eradication of ocular fungal infections: In-vitro, ex-vivo and in-vivo studies.

The most prevalent conditions among ocular surgery and COVID-19 patients are fungal eye infections, which may cause inflammation and dry eye, and may cause ocular morbidity. Amphotericin-B eye drops are commonly used in the treatment of ocular fungal infections. Lactoferrin is an iron-binding glycoprotein with broad-spectrum antimicrobial activity and is used for the treatment of dry eye, conjunctivitis, and ocular inflammation. However, poor aqueous stability and excessive nasolacrimal duct draining impede these agens' efficiency. The aim of this study was to examine the effect of Amphotericin-B, as an antifungal against Candida albicans, Fusarium, and Aspergillus flavus, and Lactoferrin, as an anti-inflammatory and anti-dry eye, when co-loaded in triblock polymers PLGA-PEG-PEI nanoparticles embedded in P188-P407 ophthalmic thermosensitive gel. The nanoparticles were prepared by a double emulsion solvent evaporation method. The optimized formula showed particle size (177.0 ± 0.3 nm), poly-dispersity index (0.011 ± 0.01), zeta-potential (31.9 ± 0.3 mV), and entrapment% (90.9 ± 0.5) with improved ex-vivo pharmacokinetic parameters and ex-vivo trans-corneal penetrability, compared with drug solution. Confocal laser scanning revealed valuable penetration of fluoro-labeled nanoparticles. Irritation tests (Draize Test), Atomic force microscopy, cell culture and animal tests including histopathological analysis revealed superiority of the nanoparticles in reducing signs of inflammation and eradication of fungal infection in rabbits, without causing any damage to rabbit eyeballs. The nanoparticles exhibited favorable pharmacodynamic features with sustained release profile, and is neither cytotoxic nor irritating in-vitro or in-vivo. The developed formulation might provide a new and safe nanotechnology for treating eye problems, like inflammation and fungal infections.

Case report: Immunological characteristics of de novo ulcerative colitis in a child post COVID-19.

The pathological mechanisms of de novo inflammatory bowel disease (IBD) following SARS-CoV-2 infection are unknown. However, cases of coexisting IBD and multisystem inflammatory syndrome in children (MIS-C), which occurs 2-6 weeks after SARS-CoV-2 infection, have been reported, suggesting a shared underlying dysfunction of immune responses. Herein, we conducted the immunological analyses of a Japanese patient with de novo ulcerative colitis following SARS-CoV-2 infection based on the pathological hypothesis of MIS-C. Her serum level of lipopolysaccharide-binding protein, a microbial translocation marker, was elevated with T cell activation and skewed T cell receptor repertoire. The dynamics of activated CD8+ T cells, including T cells expressing the gut-homing marker α4ß7, and serum anti-SARS-CoV-2 spike IgG antibody titer reflected her clinical symptoms. These findings suggest that SARS-CoV-2 infection may trigger the de novo occurrence of ulcerative colitis by impairing intestinal barrier function, T cell activation with a skewed T cell receptor repertoire, and increasing levels of anti-SARS-CoV-2 spike IgG antibodies. Further research is needed to clarify the association between the functional role of the SARS-CoV-2 spike protein as a superantigen and ulcerative colitis.

SARS-CoV-2 spike protein as a bacterial lipopolysaccharide delivery system in an overzealous inflammatory cascade.

Accumulating evidence indicates a potential role for bacterial lipopolysaccharide (LPS) in the overactivation of the immune response during SARS-CoV-2 infection. LPS is recognised by Toll-like receptor 4 (TLR4), mediating proinflammatory effects. We previously reported that LPS directly interacts with SARS-CoV-2 spike (S) protein and enhances proinflammatory activities. Using native gel electrophoresis and hydrogen-deuterium exchange mass spectrometry, we showed that LPS binds to multiple hydrophobic pockets spanning both the S1 and S2 subunits of the S protein. Molecular simulations validated by a microscale thermophoresis binding assay revealed that LPS binds to the S2 pocket with a lower affinity compared to S1, suggesting a role as an intermediate in LPS transfer. ໿Congruently, nuclear factor-kappa B (NF-κB) activation in monocytic THP-1 cells is strongly boosted by S2. Using NF-κB reporter mice followed by bioimaging, a boosting effect was observed for both S1 and S2, with the former potentially facilitated by proteolysis. The Omicron S variant binds to LPS, but with reduced affinity and LPS boosting in vitro and in vivo. Taken together, the data provide a molecular mechanism by which S protein augments LPS-mediated hyperinflammation.

Macrophage membrane-biomimetic adhesive polycaprolactone nanocamptothecin for improving cancer-targeting efficiency and impairing metastasis

The recent remarkable success and safety of mRNA lipid nanoparticle technology for producing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines has stimulated intensive efforts to expand nanoparticle strategies to treat various diseases. Numerous synthetic nanoparticles have been developed for pharmaceutical delivery and cancer treatment. However, only a limited number of nanotherapies have enter clinical trials or are clinically approved. Systemically administered nanotherapies are likely to be sequestered by host mononuclear phagocyte system (MPS), resulting in suboptimal pharmacokinetics and insufficient drug concentrations in tumors. Bioinspired drug-delivery formulations have emerged as an alternative approach to evade the MPS and show potential to improve drug therapeutic efficacy. Here we developed a biodegradable polymer-conjugated camptothecin prodrug encapsulated in the plasma membrane of lipopolysaccharide-stimulated macrophages. Polymer conjugation revived the parent camptothecin agent (e.g., 7-ethyl-10-hydroxy-camptothecin), enabling lipid nanoparticle encapsulation. Furthermore, macrophage membrane cloaking transformed the nonadhesive lipid nanoparticles into bioadhesive nanocamptothecin, increasing the cellular uptake and tumor-tropic effects of this biomimetic therapy. When tested in a preclinical murine model of breast cancer, macrophage-camouflaged nanocamptothecin exhibited a higher level of tumor accumulation than uncoated nanoparticles. Furthermore, intravenous administration of the therapy effectively suppressed tumor growth and the metastatic burden without causing systematic toxicity. Our study describes a combinatorial strategy that uses polymeric prodrug design and cell membrane cloaking to achieve therapeutics with high efficacy and low toxicity. This approach might also be generally applicable to formulate other therapeutic candidates that are not compatible or miscible with biomimetic delivery carriers. © 2022 The Authors