Molecular genetics and genomics of the ABO blood group system

The A and B oligosaccharide antigens of the ABO blood group system are produced from the common precursor, H substance, by enzymatic reactions catalyzed by A and B glycosyltransferases (AT and BT) encoded by functional A and B alleles at the ABO genetic locus, respectively. In 1990, my research team cloned human A, B, and O allelic cDNAs. We then demonstrated this central dogma of ABO and opened a new era of molecular genetics. We identified four amino acid substitutions between AT and BT and inactivating mutations in the O alleles, clarifying the allelic basis of ABO. We became the first to achieve successful ABO genotyping, discriminating between AA and AO genotypes and between BB and BO, which was impossible using immunohematological/serological methods. We also identified mutations in several subgroup alleles and also in the cis-AB and B(A) alleles that specify the expression of the A and B antigens by single alleles. Later, other scientists interested in the ABO system characterized many additional ABO alleles. However, the situation has changed drastically in the last decade, due to rapid advances in next-generation sequencing (NGS) technology, which has allowed the sequencing of several thousand genes and even the entire genome in individual experiments. Genome sequencing has revealed not only the exome but also transcription/translation regulatory elements. RNA sequencing determines which genes and spliced transcripts are expressed. Because more than 500,000 human genomes have been sequenced and deposited in sequence databases, bioinformaticians can retrieve and analyze this data without generating it. Now, in this era of genomics, we can harness the vast sequence information to unravel the molecular mechanisms responsible for important biological phenomena associated with the ABO polymorphism. Two examples are presented in this review: the delineation of the ABO gene evolution in a variety of species and the association of single nucleotide variant (SNV) sites in the ABO gene with diseases and biological parameters through genome-wide association studies (GWAS).Copyright © Annals of Blood. All rights reserved.

Development of a Novel in-Vitro Hcov-Oc43 Screening Method

Aim: To develop a simple, inexpensive antiviral screening assay, applicable to SARS-CoV-2, using a plate-based bioassay approach to assess the in-vitro activity of compounds against HCoV-OC43. Background(s): Despite the successful deployment of vaccines against SARS-CoV-2 there remains a need for effective antivirals for acute infection treatment. A distinct problem facing the search for new anti-coronavirus compounds is the cost of antiviral screening, compounded by the biosecurity concerns of live SARSCoV- 2 culture. In concert with low pathogenic surrogate virus use, the resazurin reduction assay, which is often employed for compound cytotoxicity assessments can be employed for safe, rapid and inexpensive antiviral screening. Method(s): In-vitro cell based resazurin reduction assays were optimised using remdesivir as a control compound for the assessment of anti-HCoV-OC43 activity. Following optimisation, 246 purified natural compounds from the University of Western Australia's compound collection,were screened using the resazurin bioassay as a primary screen, under pre-treatment and cotreatment conditions. Five compounds, which demonstrated anti- HCoV-OC43 activity, were chosen for secondary screening with dose responses determined using qRT-PCR. Result(s): Primary screens of the 246 compounds using the resazurin bioassay identified five compounds with a relative viral inhibition >60% and a relative cell viability >70% (Table 1). The Z factor of the pre-treatment and co-treatment assays was >0.5 (average +/- SD;0.85 +/- 0.07, 0.91 +/- 0.03 respectively). Further dose response analysis of the top five compounds identified one compound with an IC50 value <10 muM. Conclusion(s): The method developed is an appropriate primary screening tool for the identification of novel compounds with anti-HCoV-OC43 activity.Copyright © 2023 Southern Society for Clinical Investigation.

Covid-19: All facts, no myth

On December 31, 2019, the China Health Authority alerted WHO about 27 cases of pneumonia of unknown etiology in Wuhan City. It was subsequently named Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) and the disease as Coronavirus Disease 2019 (COVID-19). The disease has now become pandemic. Current review was done to summarize information on COVID-19 published in various scientific works. Electronic databases containing medical articles viz., MEDLINE/PubMed, Google Scholar etc were searched using the Medical Subject Headings 'COVID-19', '2019-nCoV', 'coronavirus' and 'SARS-CoV-2' during antecedent one year. All study designs were incorporated to harvest clinical, laboratory, imaging, and hospital course data. The intermediate host of the virus is still unknown. Respiratory droplets produced by the patient is main source of transmission. SARS-CoV-2 invades the airway epithelium by binding to angiotensin-converting enzyme-2 (ACE2) receptor with Coronavirus spike (S) protein. Most common symptoms are fever (98%), dry cough (77%), and dyspnea (63.5%). Later, complications like acute respiratory distress syndrome, septic shock etc may occur. Advanced age and co-morbidities like Diabetes have higher mortality otherwise Case Fatality Rate is 2-3%. RT-PCR is the diagnosis of choice. Since no universally accepted registered drug or FDA approved vaccine has come by now, prevention is the key. Hands should be regularly cleaned with soap or alcohol based sanitizer and in public, Nose and Mouth should be covered with face-mask and social distance of one meter should be maintained. While Vaccines are expected by early 2021, we should not forget to take comprehensive measures to prevent future outbreaks of zoonotic origin. Copyright © 2020, Kathmandu University. All rights reserved.

In silico analysis of phytochemicals and non-phytochemicals and comparing their potentiality on inhibiting nsp12 and nsp14 in SARS-CoV-2 variants

The spread of SARS-CoV-2 and its variants, leads to global pandemic endangering human life and health. The primary challenge for the scientific community is to find a potential cure for the disease which can act on the emerging variants of severe acute respiratory syndrome corona virus 2 (SARS-CoV-2). Due to the absence of effective medical treatment for the diseases, the healthcare system around the world was at a standstill. The nsp12 and nsp14 are one of the important proteins which are involved in the replication and proofreading of SARS-CoV-2 respectively. Both the non-structural proteins have highly conserved regions and served as a popular target for corona virus inhibitors for drug screening. In this study, the primary aim is to find the potential inhibitors, both phytochemical and nonphytochemical, which could act on variants to inhibit the activity of nsp12 and nsp14. Also to compare the binding affinity of nsp12 and nsp14 with phytochemicals and nonphytochemicals. A combination of mutational landscape, structure-based virtual screening and molecular dynamics (MD) simulation approaches were utilized in this work. From the mutational landscape, two functionally active mutations were observed in nsp12 and single mutation was observed in nsp14 of SARS CoV-2 Variants. The molecular simulation is performed for drugs Cepharanthine (phytochemical) and Hypericin (phytochemical) with top binding affinity for nsp12 variants and for molecules Hypericin (phytochemical) and conivaptan (non-Phytochemical) having top binding affinity with nsp14 wildtype and variants.

Functional nucleic acids as potent therapeutics against SARS-CoV-2 infection.

The COVID-19 pandemic has posed a severe threat to human life and the global economy. Although conventional treatments, including vaccines, antibodies, and small-molecule inhibitors, have been broadly developed, they usually fall behind the constant mutation of SARS-CoV-2, due to the long screening process and high production cost. Functional nucleic acid (FNA)-based therapeutics are a newly emerging promising means against COVID-19, considering their timely adaption to different mutants and easy design for broad-spectrum virus inhibition. In this review, we survey typical FNA-related therapeutics against SARS-CoV-2 infection, including aptamers, aptamer-integrated DNA frameworks, functional RNA, and CRISPR-Cas technology. We first introduce the pathogenesis, transmission, and evolution of SARS-CoV-2, then analyze the existing therapeutic and prophylactic strategies, including their pros and cons. Subsequently, the FNAs are recommended as potent alternative therapeutics from their screening process and controllable engineering to effective neutralization. Finally, we put forward the remaining challenges of the existing field and sketch out the future development directions.

Functionalized Fullerene for Inhibition of SARS-CoV-2 Variants.

As virus outbreaks continue to pose a challenge, a nonspecific viral inhibitor can provide significant benefits, especially against respiratory viruses. Polyglycerol sulfates recently emerge as promising agents that mediate interactions between cells and viruses through electrostatics, leading to virus inhibition. Similarly, hydrophobic C60 fullerene can prevent virus infection via interactions with hydrophobic cavities of surface proteins. Here, two strategies are combined to inhibit infection of SARS-CoV-2 variants in vitro. Effective inhibitory concentrations in the millimolar range highlight the significance of bare fullerene's hydrophobic moiety and electrostatic interactions of polysulfates with surface proteins of SARS-CoV-2. Furthermore, microscale thermophoresis measurements support that fullerene linear polyglycerol sulfates interact with the SARS-CoV-2 virus via its spike protein, and highlight importance of electrostatic interactions within it. All-atom molecular dynamics simulations reveal that the fullerene binding site is situated close to the receptor binding domain, within 4 nm of polyglycerol sulfate binding sites, feasibly allowing both portions of the material to interact simultaneously.

CLINICAL PROFILE OF COVID-19 INFECTION AND IMMUNE RESPONSE AFTER 3AND6 MONTH VACCINATION AGAINST SARS-COV-2 IN ADULT PATIENTS WITH TRANSFUSION-DEPENDENT THALASSAEMIATHE EXPERIENCE OF A GREEK CENTER

Background: Patients with transfusion-dependent-thalassaemia (TDT) are considered as increased risk population for severe and/or morbid COVID-19 infection. Timely vaccination is the main preventive method for severe COVID-19. Aims: To provide an overview of the clinical profile and outcome of COVID-19 infection in patients with TDT as well as to study the immune response after 3 and 6 months after vaccination against COVID-19 in adult patients with transfusion-dependent thalassaemia. Methods: This analysis focused on the evaluation in TDT patients on the long-term immune response post vaccination and on the course of COVID-19 infection and its correlation with immunization status. Serum was collected at 4 pre-defined time points, namely, just before 1st dose (TP1), 7 weeks after the 1st dose (TP2), 3 months (TP3) and 6 months (TP4) after 2nd dose. Neutralizing antibodies (NAbs) against SARS-CoV-2 were measured using FDA-approved methods. According to manufacturer, the scale of NAbs titer is 0-100%, with ≥30% considered as positive and ≥50% as clinically relevant viral inhibition. Age-matched healthy volunteers (median age: 46 years, range: 24-64 years, 24 males / 53 females) who received mRNA vaccines served as the control group for NAbs evaluation. Results: 340 (170female/170male) TDT patients older than 18 years (mean 43.6±11.5 years) followed in a single unit were included in the analysis. 270 patients (79%) were vaccinated with 2 or 3 doses. Immune response to vaccination was evaluated in 90 patients (median age: 46 years, range: 19-63 years, 40 males / 50 females). NAbs were at the level of non-immunity in all the patients at baseline (TP1) (mean 16.57% ±11.85) and showed a significant increase after the second dose (TP2) mean 86.96%±12.95 (p<0.0001). At TP3 and TP4 Nabs showed a significant decrease but remained in protective levels for the majority of the patients (mean 88.75% ±9.7 and 74.64% ±17.2 respectively(p<0.0001). The kinetics of NAbs were similar to controls except for levels at TP4 (p=0.02) (Figure 1). Up to 10/FEB/2022, 43 TDT patients (median age 43.52 range 18.6-57.9 years) were diagnosed with COVID-19, with 1 of them being infected twice. Of them, 17 were unvaccinated, 18 had received 2 doses of vaccine, while 8 had received 3 doses of the vaccine. The incidence rate was 9.6% and 24.3% for vaccinated and unvaccinated patients, respectively. The severity of the COVID-19 for vaccinated and unvaccinated patients were as follows, respectively, ;Grade 1 (asymptomatic): 0 and 1, Grade 2 (mild symptoms, symptomatic therapy, no COVID19 specific therapy): 23 and 9, Grade 3 (mild symptoms, symptomatic therapy, with COVID19 specific therapy): 1 and 3, Grade 4 (moderate: pneumonia, thrombophlebitis, Hospitalization): 2 and 3, Grade 5 (Hospitalization requiring ICU, death): 0 and 1. Thrombotic event was documented in 1 patient. All patients except one from unvaccinated group are alive. Summary/Conclusion: Immune response to vaccination may wean faster in TDT patients. in Unvaccinated TDT patients were more likely to be infected and to develop more serious COVID-19 infection compared to vaccinated patients. (Figure Presented).

A Novel Host-Targeted Viral Assembly Inhibitor Blocks SARS-CoV-2 in Airway Epithelial Cells

Introduction: The rapid emergence of the SARS-CoV-2 Omicron variant that evades many monoclonal antibody therapies illustrates the need for anti-viral treatments with low susceptibility to evolutionary escape. The small molecule PAV-104, identified through a moderate-throughput screen involving cell-free protein synthesis, was recently shown to target a subset of host protein assembly machinery in a manner specific to viral assembly. This compound has minimal host toxicity, including once daily oral dosing in rats that achieves >200-fold of the 90% effective concentration (EC90) in blood. The chemotype shows broad activity against respiratory viral pathogens, including Orthomyxoviridae, Paramyxoviridae, Adenoviridae, Herpesviridae, and Picornaviridae, with low suceptability to evolutionary escape. We hypothesized that PAV-104 would be active against SARSCoV- 2 variants in human airway epithelial cells. Methods: Airway epithelial cells were differentiated from lung transplant tissue at air-liquid interface (ALI) for four weeks prior to challenge with Alpha (Pango lineage designation B.1.1.7), Beta (B.1.351), Gamma (P.1), and Delta (B.1.617.2) SARS-CoV-2 variants. Viral replication was determined by quantitative PCR measurement of the SARS-CoV-2 nucleocapsid (N) gene. Dose-dependent virus inhibition and cytotoxicity of PAV-104 in the Calu-3 airway epithelial cell line was determined by PCR and MTT assay. Student's t-tests were used to evaluate statistical significance. Results: Alpha, Beta, Gamma, and Delta variants of SARS-CoV-2 showed comparable infectivity in human primary airway epithelial cells at ALI (N=3 donors), 47- to 550-fold higher than the parent (USA-WA1/2020) strain. PAV-104 reached 50% cytotoxicity in Calu-3 cells at 240 nM (Fig. 1A). Dose-response studies in Calu-3 cells demonstrated PAV-104 has a 6 nM 50% inhibitory concentration (IC50) for blocking replication of SARS-CoV-2 (USA-WA1/2020) (Fig.1B). In primary cells at ALI from 3 donors tested, there was >99% inhibition of infection by SARS-CoV-2 Gamma variant (N=3, MOI 0.1, P <0.01) with 100 nM PAV-104 (Fig. 1C). Addition of 100 nM PAV-104 2-hours post-infection, but not pre-infection, resulted in >99% suppression of viral replication, indicating a post-entry drug mechanism. PAV-104 bound a small subset of the known allosteric modulator 14-3-3, itself implicated in the interactome of SARS-CoV-2. Conclusion: PAV-104 is a host-targeted, orally bioavailable, pan-viral small molecule inhibitor with promising activity against SARS-CoV-2 variants in human primary airway epithelial cells. (Figure Presented).

Water Soluble Tocopherol Derivatives Inhibit the SARS-CoV-2 RNADependent RNA Polymerase

Rationale The recent emergence of a novel coronavirus, SARS-CoV-2, has led to the global pandemic of the severe disease COVID-19 in humans. While efforts to quickly identify effective antiviral therapies have focused largely on repurposing existing drugs, the current standard of care, remdesivir, remains the only authorized antiviral intervention of COVID-19 and provides only modest clinical benefits. Thus, new antivirals targeting SARS-CoV-2 are urgently needed. Methods Artificial intelligence algorithm MediKanren was used to query FDA-approved and late-stage drug compounds for potential interactions with SARS-CoV-2 proteins, coronaviruses, and host cell networks for possible antiviral activity. From this, 157 compounds were further tested in an antiviral screen against live SARS-CoV-2 for reduction in viral growth. Select compounds were further assessed for synergistic activity with remdesivir. Both in vitro and cell free systems identified tocopherol succinate compounds that inhibited the RNA-dependent RNA polymerase (RdRp). Validation of antiviral and synergistic activity was performed in primary human airway epithelial cell cultures against multiple SARS-CoV-2 variants.Results Here we show that water-soluble derivatives of α-tocopherol have potent antiviral activity and synergize with remdesivir as inhibitors of the SARS-CoV-2 (RdRp). Through an artificial-intelligence-driven in silico screen and in vitro viral inhibition assay, we identified D-α-tocopherol polyethylene glycol succinate (TPGS) as an effective antiviral against SARS-CoV-2 and β-coronaviruses more broadly that also displays strong synergy with remdesivir. We subsequently determined that TPGS and other water-soluble derivatives of α- tocopherol inhibit the transcriptional activity of purified SARS-CoV-2 RdRp and identified affinity binding sites for these compounds within a conserved, hydrophobic interface between SARS-CoV- 2 nonstructural protein 7 and nonstructural protein 8 that is functionally implicated in the assembly of the SARS-CoV-2 RdRp. Conclusion In summary, solubilizing modifications to α-tocopherol allow it to interact with the SARS-CoV-2 RdRp, making it an effective antiviral molecule alone and even more so in combination with remdesivir. These findings are significant given that many tocopherol derivatives, including TPGS, are considered safe for humans, orally bioavailable, and dramatically enhance the activity of the only approved antiviral for SARS-CoV-2 infection.

Dose-Dependent Respiratory Viral Inhibition by a Safe Inhaled Alkaline Treatment

Introduction: SARS-CoV-2 respiratory infection is pandemic and continues to cause significant mortality and morbidity worldwide. Respiratory viral infections in general are a leading cause of hospital admissions and mortality throughout the world as well. Most respiratory viral infections require an acidic intracellular and endosomal environment in order to enter host cells, replicate, and cause illness. We study the beneficial effects of airway alkalinization by an inhaled drug, Optate, that we currently have demonstrated is safe to inhale by healthy subjects and those with stable airways disease. We have recently shown that treatment with 4.5 mg/ml Optate safely inhibits SARS-CoV-2 infection in primary human airway epithelial cells (HAECs). We hypothesized that this inhibition would be dose dependent and that Optate would also inhibit other viral infections in a dosedependent manner. Methods: HAECs were infected with respiratory syncytial virus with green fluorescent protein (RSV-GFP) or SARS-CoV-2 virus. A dose-response curve of Optate was performed in each infection model and compared to a control group. Viral infection was quantified using fluorescence microscopy, plaque assays, and viral protein quantification. Optate pH was measured at each dose and a corresponding dose/pH curve was calculated to compare pH to dose-response. Results: SARS-CoV-2 infection was significantly inhibited by doses of Optate > 2.25 mg/ml, corresponding with an Optate pH > 9.2 (n = 4, p < 0.001). RSV infection was significantly inhibited by doses of Optate > 2 mg/ml, corresponding with an Optate pH > 9 (n = 3, p < 0.001). No significant difference was noted between control and Optate treated HAECs at lower concentrations of Optate. Conclusions: Optate inhibits SARS-CoV-2 and RSV viral infections in a dose-dependent manner that correlates with Optate pH. These findings suggest that Optate may be an inhaled therapeutic for patients with respiratory viral infections. (Table Presented).

Molecular docking and dynamic simulations study for repurposing of multitarget coumarins against SARS-CoV-2 main protease, papain-like protease and RNA-dependent RNA polymerase

Proteases and RNA-Dependent RNA polymerase, major enzymes which are essential targets involved in the life and replication of SARS-CoV-2. This study aims at in silico examination of the potential ability of coumarins and their derivatives to inhibit the replication of SARS-Cov-2 through multiple targets, including the main protease, papain-like protease and RNA-Dependent RNA polymerase. Several coumarins as biologically active compounds were studied, including coumarin antibiotics and some naturally reported antiviral coumarins. Aminocoumarin antibiotics, especially coumermycin, showed a high potential to bind to the enzymes' active site, causing possible inhibition and termination of viral life. They demonstrate the ability to bind to residues essential for triggering the crucial cascades within the viral cell. Molecular dynamics simulations for 50 ns supported these data pointing out the formation of rigid, stable Coumermycin/enzyme complexes. These findings strongly suggest the possible use of Coumermycin, Clorobiocin or Novobiocin in the fight against COVID-19, but biological evidence is still required to support such suggestions.

Humoral immune response to mRNA COVID-19 vaccine in Puerto Ricans with IBD does not differ between class of biologics

Background: The COVID-19 vaccine trials did not include subjects with IBD or immunosuppression, limiting the effectiveness data of the vaccine in this population. The impact of biologics with different mechanisms of action on antibody concentrations and neutralizing capacity produced by the vaccine may alter prevention strategies. We aim to describe a comparison of the humoral response to COVID-19 vaccine in patients with IBD on biologics between different therapies and a control group. Methods: Patients ≥21 years of age with Crohn's disease (CD) and ulcerative colitis (UC) on biologic therapy were recruited. Blood samples were collected at 14 ± 2 days (Cohort 1) and 60 ±7 days (Cohort 2) after receiving a 2nd dose of mRNA COVID-19 vaccine [BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna). Anti-spike protein receptor binding domain IgG levels and neutralizing capability using SARS-CoV-2 surrogate virus neutralization test (sVNT%) were measured. A result >30% is positive for effective viral inhibition. Results were stratified by mechanism of action of the drug and compared with a healthy control group. Comparisons were evaluated by Kruskal-Walls test and Dunns Pairwise/Bonferroni. The study is approved by the MSC IRB. Results: 32 subjects exposed to biological therapy divided into 2 cohorts (14-days, n=19/60-days, n=13) and 18 samples of healthy controls (14-days, n=12/60-days, n=6) are reported. Of the IBD subjects, 81% (26/32) had CD, 56% were males (18/32) and mean age was 39. All subjects were receiving biological monotherapy, one subject was also on azathioprine. All groups developed detectable antibody levels and >60% neutralizing antibody detection after 14 and 60 days of the second vaccine dose. IgG levels at 14 days (p<0.001) and sVNT% at 14- and 60-days post second vaccine dose (p=0.007, 0.024) were significantly different between subjects vs. controls. When stratified by mechanism of action, there was a significant difference between each biologic vs. control (p<0.001), but no difference between biologic classes. Initial analysis for the sVNT% at 14 days showed statistical significance (p=0.046). Post-hoc analysis showed no statistical significance in the individual comparisons. No significant differences were found between each therapy vs. control for IgG levels nor sVNT% at 60-days (p=0.257, 0.113). Conclusion: Our study shows that IBD patients on biological therapy who receive a COVID-19 vaccine develop a lower but effective humoral response up to 60 days after the second dose when compared to healthy individuals. No difference was found between class of biologics. A larger sample is needed.

Poor Neutralizing Antibody Responses in Patients with CLL, NHL and HL after Vaccination Against Sars-Cov-2;A Prospective Study in 132 Patients

Introduction: Recent data suggest a suboptimal antibody response to COVID-19 vaccination in patients with hematological malignancies, especially under therapy with monoclonal antibodies targeting B-cells. Herein, we evaluated the development of neutralizing antibodies (NAbs) against SARS-CoV-2 in patients with chronic lymphocytic leukemia (CLL), Non-Hodgkin Lymphoma (NHL) and Hodgkin's Lymphoma (HL) after vaccination with the mRNA BNT162b2 vaccine, up to 50 days post their first vaccine dose. Methods: This is a large prospective study (NCT04743388) evaluating the kinetics of anti-SARS-CoV-2 antibodies after COVID-19 vaccination in healthy subjects and patients with hematological malignancies. We report here the results in CLL, NHL and HL patients in comparison to age- and gender-matched controls who were vaccinated at the same time period (January to May 2021). After vein puncture, the serum of both patients and controls was collected on day 1 (D1;before the first BNT162b2 dose), on day 22 (D22;before the second dose of the BNT162b2) and on day 50 (D50;3 weeks post second dose of the BNT162b2). Serum was separated within 4 hours from blood collection and stored at -80°C until the day of measurement. NAbs against SARS-CoV-2 were measured using FDA approved methodology (ELISA, cPass™ SARS-CoV-2 NAbs Detection Kit;GenScript, Piscataway, NJ, USA) on the abovementioned timepoints. A NAb titer of at least 30% is considered as positive, according to manufacturer, whereas a NAb titer of at least 50% has been associated with clinically relevant viral inhibition [Walsh et al. N Engl J Med 2020, 383, 2439-50]. Samples of the same individual were measured in the same ELISA plate. Results: We evaluated 132 patients with CLL/Lymphomas after vaccination with the BNT162b2. Patient population included 53 with CLL, 57 with NHL and 22 with HL, while 214 healthy controls, of similar age and gender, were also studied. At the time of vaccination, 30% (n=40) of patients had asymptomatic disease and out of 92 symptomatic patients, 49% (n=45) were on active treatment. Vaccination with two doses of the BNT162b2 led to lower production of NAbs against SARS-CoV-2 in patients compared with controls, both on day 22 and on day 50 (P<0.001 for all comparisons) for all subgroups. After the first dose of the vaccine, on D22, the patient group had lower NAb titers compared with controls: the median NAb inhibition titer was 18% (IQR: 8.5-29%) for patients versus 41.6% (IQR: 25.3-59%) for controls;p<0.001. On D50, the median NAb inhibition titer was 32.5% (IQR: 13.5-93%) for patients versus 94.7% (IQR: 89-97%) for controls;p<0.001. More specifically, only 50.8% (67/132) of the patients versus 98.1% (210/214) of the controls developed NAb titers ≥30% and 43.9% (58/132) of patients versus 95.3% (204/214) titers ≥50% (high protective titers) at day 50 (p<0.0001 for all comparisons;Figure-left part). Importantly, active treatment (which included anti-CD antibodies, Bruton's tyrosine kinase inhibitors, a combination of the above, chemotherapy-only regimens or Bcl-2 inhibitors) was an independent prognostic factor for suboptimal antibody response at day 50 (<50%) in the patient subgroup (p<0.001). Rituximab administration in the last 12 months correlated with decreased antibody response at day 50 (p<0.01). Patients with HL were more likely to achieve humoral responses (>50% at day 50) compared to other disease types (p<0.05;Figure-right part). Disease-related immune dysregulation and therapy-related immunosuppression were therefore involved in the low humoral responses seen in patients. Regarding adverse events, 9% and 9.8% patients reported mild reactions after the first and second dose of the BNT162b2 vaccine, respectively. Conclusion: Patients with CLL/NHL/HL have a low humoral response following SARS-CoV-2 vaccination, particularly patients who are on active treatment with rituximab or BTK inhibitors. These patient subgroups therefore should continue utilizing protective measures against SARS-CoV-2 (masks, social distancing, etc) as they re at high risk for COVID-19. Further studies on the kinetics of immune subpopulations following COVID-19 vaccination will elucidate the underlying immune landscape and determine the potential need for additional booster vaccine doses or protective administration of antibodies against SARS-CoV-2 in CLL/NHL/HL patients with poor response after full vaccination. [Formula presented] Disclosures: Terpos: Sanofi: Consultancy, Honoraria, Research Funding;Novartis: Honoraria;Celgene: Consultancy, Honoraria, Research Funding;Janssen-Cilag: Consultancy, Honoraria, Research Funding;GSK: Honoraria, Research Funding;Genesis: Consultancy, Honoraria, Research Funding;Takeda: Consultancy, Honoraria, Research Funding;BMS: Honoraria;Amgen: Consultancy, Honoraria, Research Funding. Gavriatopoulou: Janssen: Honoraria;GSK: Honoraria;Genesis: Honoraria;Takeda: Honoraria;Sanofi: Honoraria;Amgen: Honoraria;Karyopharm: Honoraria. Baltadakis: Amgen: Honoraria;Bristol-Myers Squibb: Honoraria;Alexion: Honoraria;Astellas: Honoraria;Pfizer: Honoraria, Other: Travel Grants;Gilead: Honoraria;Novartis: Honoraria;Abbvie: Honoraria;Genesis Pharma: Other: Travel Grants;Gilead: Other: Travel Grants;WinMedica: Other: Travel Grants;Baxalta Hellas: Other: Travel Grants. Dimopoulos: BMS: Honoraria;Amgen: Honoraria;Janssen: Honoraria;Takeda: Honoraria;Beigene: Honoraria.

Antibody Response after Vaccination for Sars-Cov-2 in Patients with AL Amyloidosis and the Impact of Therapy

Patients with lymphoproliferative disorders are at high risk for severe COVID-19. For patients with AL amyloidosis, in which there is also critical organ involvement, this risk may be even higher. Vaccination against SARS-CoV-2 is the best strategy to avoid severe COVID-19, but response to vaccines may be compromised in patients with B-cell lymphoproliferative or plasma cell malignancies, as in AL amyloidosis. Although modest in size, the plasma cell clone in AL may cause immunosuppression while anticlonal therapies further compromise immune responses. To evaluate immunization efficacy, we measured the titers of neutralizing antibodies (NAbs) against SARS-CoV-2 after vaccination with BNT162b2 in patients with AL amyloidosis. As a control group we used volunteers, matched (ratio 1:2) for age and gender, who had no autoimmune or active malignant or infectious disease. Serum was separated within 4 hours from blood collection and stored at -80°C until the day of measurement on (A) day 1 (D1;before the first dose of BNT162b2) (B) day 22 (D22;before the 2nd dose) and (C) day 50 (D50;ie 30 days after the 2nd dose). NAbs against SARS-CoV-2 were measured using FDA approved methodology (cPass™ SARS-CoV-2 NAbs Detection Kit;GenScript, Piscataway, NJ, USA). According to the manufacturer of the assay, a titer ≥ 50% is considered a clinically relevant threshold for viral inhibition. The study included 144 patients with AL amyloidosis, of which 120 had NAbs titers assessed on all time points and were included in the final analysis (53% males;median age: 66, IQR: 57-72 years) and 240 matched controls (53% males;median age: 66, IQR: 57-72 years). 66 (55%) AL patients were on active therapy, 17.5% were on daratumumab (DARA)-based therapy, 52 (43%) had discontinued therapy >3 months from the date of the first shot, 19% had prior exposure to DARA and 94 (78%) were in hematologic remission (CR or VGPR). Prior to the 1st dose (D1), NAb titers were similar between patients and controls (median 14.9% (IQR 7.8-23.1%) vs 14% (IQR 6.8-22.9%), p=0.439);6 AL patients had baseline NAbs >50%, of which 5 reported a history of COVID-19 infection. On D22, there was a significant increase of NAbs titers both in controls and AL patients (both p<0.001);however, median NAb titer was 23.6% (IQR 12.4-37.7%) in AL patients vs 47.5% (IQR 32.1-62.7%) in controls (p<0.001) and 20.5% of AL patients vs 46.7% of controls (p<0.001) developed NAb titers ≥50%. On D50, there was further increase in NAbs titers both in controls and AL patients (both p<0.001) and median NAb titer for AL patients was 83.1% (IQR 41.5-94.9%) vs 95.6% (IQR 91.7-97.2%) in controls (p<0.001);71% of AL patients vs 98% of matched controls (p<0.001) developed NAb titers ≥50%. Among AL patients, factors associated with NAb titers on D50 included age (p<0.001), lymphocyte counts (p<0.001), serum albumin (p<0.001) and amount of proteinuria at the time of vaccination (p=0.047), renal involvement (p=0.047), use of steroids (p<0.001), active treatment (p<0.001), treatment-free interval (p=0.001), remission status (CR/VGPR) (p=0.018). There was no significant association with gender (p=0.092), BMI (p=0.198), IgG (0.099), IgA (p=0.789) or IgM levels (p=0.687), liver (p=0.521) or heart involvement (p=0.141). Patients on therapy had lower NAb titers at D50 (median 50.1% (IQR 25.3-84.1%) vs 91.6% (IQR 74.5-96.5%) for those not on treatment, p<0.001), so that 51% had a D50 NAb titer ≥50% vs 87% of those not on therapy. Current DARA therapy (median 52.1% vs 46.4% without DARA, p=0.486) or prior exposure to DARA (92.1% vs 91.2%, p=0.966) were not associated with D50 NAb titers. Generalized linear models were used for evaluation of multiple factors associated with D50 NAb titers: at least 3 months since the last dose of anticlonal therapy (p<0.001), lymphocyte counts (p=0.001) and serum albumin levels at the time of vaccination (p=0.020) were independent predictors of NAb titers on D50. When seroconversion was defined as a NAb titer ≥50% at D50, then >3 months of treatment-free interva (HR:7.75, p<0.001,) was the strongest factor associated with seconversion. In conclusion, patients with AL amyloidosis have an attenuated response to vaccination with BNT162b2 especially among those on active therapy or with less than 3 months since the last dose of treatment. For such patients, an anamnestic dosing strategy could be considered, especially after completion of anticlonal therapy. [Formula presented] Disclosures: Kastritis: Genesis Pharma: Honoraria;Janssen: Consultancy, Honoraria, Research Funding;Takeda: Honoraria;Pfizer: Consultancy, Honoraria, Research Funding;Amgen: Consultancy, Honoraria, Research Funding. Terpos: Novartis: Honoraria;Janssen: Consultancy, Honoraria, Research Funding;Genesis: Consultancy, Honoraria, Research Funding;Celgene: Consultancy, Honoraria, Research Funding;BMS: Honoraria;Amgen: Consultancy, Honoraria, Research Funding;Takeda: Consultancy, Honoraria, Research Funding;Sanofi: Consultancy, Honoraria, Research Funding;GSK: Honoraria, Research Funding. Gavriatopoulou: Sanofi: Honoraria;GSK: Honoraria;Karyopharm: Honoraria;Takeda: Honoraria;Genesis: Honoraria;Janssen: Honoraria;Amgen: Honoraria. Dimopoulos: Amgen: Honoraria;BMS: Honoraria;Janssen: Honoraria;Takeda: Honoraria;BeiGene: Honoraria.

Antiviral nanoparticles for sanitizing surfaces: A roadmap to self-sterilizing against COVID-19.

Nanoparticles provide new opportunities in merging therapeutics and new materials, with current research efforts just beginning to scratch the surface of their diverse benefits and potential applications. One such application, the use of inorganic nanoparticles in antiseptic coatings to prevent pathogen transmission and infection, has seen promising developments. Notably, the high reactive surface area to volume ratio and unique chemical properties of metal-based nanoparticles enables their potent inactivation of viruses. Nanoparticles exert their virucidal action through mechanisms including inhibition of virus-cell receptor binding, reactive oxygen species oxidation and destructive displacement bonding with key viral structures. The prevention of viral outbreaks is one of the foremost challenges to medical science today, emphasizing the importance of research efforts to develop nanoparticles for preventative antiviral applications. In this review, the use of nanoparticles to inactivate other viruses, such as influenza, HIV-1, or norovirus, among others, will be discussed to extrapolate broad-spectrum antiviral mechanisms that could also inhibit SARS-CoV-2 pathogenesis. This review analyzes the published literature to highlight the current state of knowledge regarding the efficacy of metal-based nanoparticles and other antiviral materials for biomedical, sterile polymer, and surface coating applications.

The Use of Lectins as Tools to Combat SARS-CoV-2.

BACKGROUND: In December 2019, China announced the first case of an infection caused by an, until then, unknown virus: SARS-CoV-2. Since then, researchers have been looking for viable alternatives for the treatment and/or cure of viral infection. Among the possible complementary solutions are lectins, proteins that are reversibly bound to different carbohydrates. The Spike protein, present on the viral surface, can interact with different cell receptors: ACE2, CD147, and DC-SIGNR. Since lectins have an affinity for different carbohydrates, the binding with the glycosylated cell receptors represents a possibility of preventing the virus from binding to the receptors of host cells. OBJECTIVE: In this review, we discuss the main lectins that are possible candidates for use in the treatment of Covid-19, highlighting those that have already demonstrated antiviral activity in vivo and in vitro, including mannose-binding lectin, Griffithsin, BanLec, and others. We also aim to discuss the possible mechanism of action of lectins, which appears to occur through the mediation of viral fusion in host cells, by binding of lectins to glycosylated receptors found in human cells and/or binding of these proteins with the spike glycoprotein, present in virus surface. Moreover, we discuss the use of lectins in clinical practice. CONCLUSION: Even with the development of effective vaccines, new cases of viral infection with the same virus, or new outbreaks with different viruses can occur; so, the development of new treatments should not be discarded. Moreover, the discussions made in this work are relevant regarding the anti-viral properties of lectins.

A Novel Small Molecule Inhibits Hepatitis C Virus Propagation in Cell Culture.

Hepatitis C virus (HCV) can cause acute and chronic infection that is associated with considerable liver-related morbidity and mortality. In recent years, there has been a shift in the treatment paradigm with the discovery and approval of agents that target specific proteins vital for viral replication. We employed a cell culture-adapted strain of HCV and human hepatoma-derived cells lines to test the effects of our novel small-molecule compound (AO13) on HCV. Virus inhibition was tested by analyzing RNA replication, protein expression, and virus production in virus-infected cells treated with AO13. Treatment with AO13 inhibited virus spread in cell culture and showed a 100-fold reduction in the levels of infectious virus production. AO13 significantly reduced the level of viral RNA contained within cell culture fluids and reduced the cellular levels of HCV core protein, suggesting that the compound might act on a late step in the viral life cycle. Finally, we observed that AO13 did not affect the release of infectious virus from infected cells. Docking studies and molecular dynamics analyses suggested that AO13 might target the NS5B RNA polymerase, however, real-time RT-PCR analyses of cellular levels of HCV RNA showed only an ∼2-fold reduction in viral RNA levels in the presence of AO13. Taken together, this study revealed that AO13 showed consistent, but low-level antiviral effect against HCV, although the mechanism of action remains unclear. IMPORTANCE The discovery of curative antiviral drugs for a chronic disease such as HCV infection has encouraged drug discovery in the context of other viruses for which no curative drugs currently exist. Since we currently face a novel virus that has caused a pandemic, the need for new antiviral agents is more apparent than ever. We describe here a novel compound that shows a modest antiviral effect against HCV that could serve as a lead compound for future drug development against other important viruses such as SARS-CoV-2.

Graphene-Assisted Synthesis of 2D Polyglycerols as Innovative Platforms for Multivalent Virus Interactions.

2D nanomaterials have garnered widespread attention in biomedicine and bioengineering due to their unique physicochemical properties. However, poor functionality, low solubility, intrinsic toxicity, and nonspecific interactions at biointerfaces have hampered their application in vivo. Here, biocompatible polyglycerol units are crosslinked in two dimensions using a graphene-assisted strategy leading to highly functional and water-soluble polyglycerols nanosheets with 263 ± 53 nm and 2.7 ± 0.2 nm average lateral size and thickness, respectively. A single-layer hyperbranched polyglycerol containing azide functional groups is covalently conjugated to the surface of a functional graphene template through pH-sensitive linkers. Then, lateral crosslinking of polyglycerol units is carried out by loading tripropargylamine on the surface of graphene followed by lifting off this reagent for an on-face click reaction. Subsequently, the polyglycerol nanosheets are detached from the surface of graphene by slight acidification and centrifugation and is sulfated to mimic heparin sulfate proteoglycans. To highlight the impact of the two-dimensionality of the synthesized polyglycerol sulfate nanosheets at nanobiointerfaces, their efficiency with respect to herpes simplex virus type 1 and severe acute respiratory syndrome corona virus 2 inhibition is compared to their 3D nanogel analogs. Four times stronger in virus inhibition suggests that 2D polyglycerols are superior to their current 3D counterparts.

Carrageenan-containing over-the-counter nasal and oral sprays inhibit SARS-CoV-2 infection of airway epithelial cultures.

Pharmaceutical interventions are urgently needed to prevent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and transmission. As SARS-CoV-2 infects and spreads via the nasopharyngeal airways, we analyzed the antiviral effect of selected nasal and oral sprays on virus infection in vitro. Two nose sprays showed virucidal activity but were cytotoxic precluding further analysis in cell culture. One nasal and one mouth spray suppressed SARS-CoV-2 infection of TMPRSS2-expressing Vero E6 cells and primary differentiated human airway epithelial cultures. The antiviral activity in both sprays could be attributed to polyanionic ι- and κ-carrageenans. Thus, application of carrageenan-containing nasal and mouth sprays may reduce the risk of acquiring SARS-CoV-2 infection and may limit viral spread, warranting further clinical evaluation.