Complement Activation by an Anti-Dengue/Zika Antibody with Impaired Fcγ Receptor Binding Provides Strong Efficacy and Abrogates Risk of Antibody-Dependent Enhancement.

To combat infectious diseases, vaccines are considered the best prophylactic strategy for a wide range of the population, but even when vaccines are effective, the administration of therapeutic antibodies against viruses could provide further treatment options, particularly for vulnerable groups whose immunity against the viruses is compromised. Therapeutic antibodies against dengue are ideally engineered to abrogate binding to Fcγ receptors (FcγRs), which can induce antibody-dependent enhancement (ADE). However, the Fc effector functions of neutralizing antibodies against SARS-CoV-2 have recently been reported to improve post-exposure therapy, while they are dispensable when administered as prophylaxis. Hence, in this report, we investigated the influence of Fc engineering on anti-virus efficacy using the anti-dengue/Zika human antibody SIgN-3C and found it affected the viremia clearance efficacy against dengue in a mouse model. Furthermore, we demonstrated that complement activation through antibody binding to C1q could play a role in anti-dengue efficacy. We also generated a novel Fc variant, which displayed the ability for complement activation but showed very low FcγR binding and an undetectable level of the risk of ADE in a cell-based assay. This Fc engineering approach could make effective and safe anti-virus antibodies against dengue, Zika and other viruses.

Harringtonine: A more effective antagonist for Omicron variant.

Fusion with host cell membrane is the main mechanism of infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we propose that a new strategy to screen small-molecule antagonists blocking SARS-CoV-2 membrane fusion. Using cell membrane chromatography (CMC), we found that harringtonine (HT) simultaneously targeted SARS-CoV-2 S protein and host cell surface TMPRSS2 expressed by the host cell, and subsequently confirmed that HT can inhibit membrane fusion. HT effectively blocked SARS-CoV-2 original strain entry with the IC50 of 0.217 µM, while the IC50 in delta variant decreased to 0.101 µM, the IC50 in Omicron BA.1 variant was 0.042 µM. Due to high transmissibility and immune escape, Omicron subvariant BA.5 has become the dominant strain of the SARS-CoV-2 virus and led to escalating COVID-19 cases, however, against BA.5, HT showed a surprising effectiveness. The IC50 in Omicron BA.5 was even lower than 0.0019 µM. The above results revealed the effect of HT on Omicron is very significant. In summary, we characterize HT as a small-molecule antagonist by direct targeting on the Spike protein and TMPRSS2.

Waning of specific antibodies against Delta and Omicron variants five months after a third dose of BNT162b2 SARS-CoV-2 vaccine in elderly individuals.

The emergence of new SARS-CoV-2 variants, such as the more transmissible Delta and Omicron variants, has raised concerns on efficacy of the COVID-19 vaccines. Here, we examined the waning of antibody responses against different variants following primary and booster vaccination. We found that antibody responses against variants were low following primary vaccination. The antibody response against Omicron was almost non-existent. Efficient boosting of antibody response against all variants, including Omicron, was observed following a third dose. The antibody response against the variants tested was significantly higher at one month following booster vaccination, compared with two months following primary vaccination, for all individuals, including the low antibody responders identified at two months following primary vaccination. The antibody response, for all variants tested, was significantly higher at four months post booster than at five months post primary vaccination, and the proportion of low responders remained low (6-11%). However, there was significant waning of antibody response in more than 95% of individuals at four months, compared to one month following booster. We also observed a robust memory B cell response following booster, which remained higher at four months post booster than prior to booster. However, the memory B cell responses were on the decline for 50% of individuals at four months following booster. Similarly, while the T cell response is sustained, at cohort level, at four months post booster, a substantial proportion of individuals (18.8 - 53.8%) exhibited T cell response at four months post booster that has waned to levels below their corresponding levels before booster. The findings show an efficient induction of immune response against SARS-CoV-2 variants following booster vaccination. However, the induced immunity by the third BNT162b2 vaccine dose was transient. The findings suggest that elderly individuals may require a fourth dose to provide protection against SARS-CoV-2.

Mediating effect of mindfulness level on the relationship between marital quality and postpartum depression among primiparas.

BACKGROUND: Postpartum depression refers to a depressive episode or depressive symptoms up to 12 mo after delivery. Trait mindfulness has presented a protective factor for postpartum depressive symptoms and proved efficient in improving relationship satisfaction among couples. AIM: To investigate the correlations among mindfulness, marital quality, anxiety, and depression in a large city in western China during the post-corona virus infectious disease-2019 era and determine whether trait mindfulness mediates the relationship between marital quality and postpartum anxiety and depression among primiparas. METHODS: A cross-sectional study was conducted. The self-administered questionnaire was submitted online through smartphones. The levels of mindfulness, anxiety, depression, and marital quality were respectively investigated by the mindful attention awareness scale (MAAS), the self-rating anxiety scale (SAS), the self-rating depression scale (SDS), and the marriage perception scale (MPS) in these enrolled Han and Tujia primiparas. RESULTS: No statistical significance was observed in the prevalence of postpartum anxiety and depression, nor scores of MAAS and MPS-Total in different regions or ethnicities (P > 0.05). However, MPS-Marital interaction (P < 0.05), MPS-Family relationship (MPS-FR) (P < 0.01), and MPS-Marital conflict (MPS-MC) (P < 0.01) scores of urban primiparas were higher than those of rural primiparas. The MPS-MC score of Han primiparas was higher than that of Tujia primiparas (P < 0.05). Negative correlations were observed between MAAS and SAS (r = -0.457, P < 0.01), and MAAS and SDS (r = -0.439, P < 0.01). SAS has revealed a highly positive correlation with SDS (r = 0.720, P < 0.01) and a weak negative correlation with MPS (r = -0.200, P < 0.05). Besides, a weak negative correlation was observed between MAAS and MPS-MC (r = -0.184, P < 0.05), and a weak positive correlation was noticed between SAS and MPS-MC (r = -0.225, P < 0.01). Mediation analysis demonstrated a full mediation effect of mindfulness level on the relationship between MPS-FR and postpartum anxiety (P < 0.05, 95%CI: -0.384 to 0.033), MPS-MC and postpartum anxiety (P < 0.01, 95%CI: 0.027-0.193), MPS-FR and postpartum depression (P < 0.05, 95%CI: -0.365 to 0.031), and MPS-MC and postpartum depression (P < 0.01, 95%CI: 0.022-0.206). CONCLUSION: Mindfulness demonstrates negative correlations with marital conflict, postpartum anxiety and depression, and it may have cross-ethnic and trans-regional characteristics. Although the mindfulness levels have revealed no significant mediating effect between the total score of marital quality and postpartum depression in this study, it demonstrates a full mediation effect on the relationships between family relationships, marital conflict, and postpartum anxiety and depression.

The Association Between Inhaled Corticosteroid and the Risks of SARS-COV-2 infection: A systematic review and meta-analysis

Background The effect of inhaled corticosteroid (ICS) on the risk of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infection is unclear. Methods We performed a systematic review and meta-analysis of clinical studies that assessed the association between the use of ICS and the risk of SARS-COV-2 infection. PubMed, Web of Science, Scopus, Cochrane Library and Google Scholar were searched to January 1st, 2023. ROBINS-I was used to assess risk of bias of included studies. The outcome of interest was the risk of SARS-COV-2 infection in patients and odds ratio (OR) with 95% confidence interval (95% CI) were calculated using Comprehensive Meta-analysis software version 3. Results Twelve studies involving seven observational cohort studies, three case-control studies, and two cross-sectional studies were included in this meta-analysis. Overall, compared to non-ICS use, the pooled odds ratio (OR) of the risk of SARS-COV-2 infection was 0.997 (95% confidence interval [CI] 0.664-1.499;p=0.987) for patients with ICS use. Subgroup analyses demonstrated no statistical significance in the increased risk of SARS-COV-2 infection in patients with ICS monotherapy or in combination with bronchodilators (pooled OR=1.408;95% CI=0.693-2.858;p=0.344 in ICS monotherapy, and pooled OR=1.225;95% CI=0.533-2.815;p=0.633 in ICS combination, respectively). In addition, no significant association was observed between ICS use and the risk of SARS-COV-2 infection for patients with COPD (pooled OR=0.715;95% CI=0.415-1.230;p=0.225) and asthma (pooled OR=1.081;95% CI=0.970-1.206;p=0.160). Conclusions The use of ICS, either monotherapy or in combination with bronchodilators, does not have impact on the risk of SARS-COV-2 infection. Data availability The datasets used and analysed in the current study are available from the corresponding author on reasonable request.

The association between inhaled corticosteroid and the risks of SARS-COV-2 infection: A systematic review and meta-analysis.

BACKGROUND: The effect of inhaled corticosteroid (ICS) on the risk of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infection is unclear. METHODS: We performed a systematic review and meta-analysis of clinical studies that assessed the association between the use of ICS and the risk of SARS-COV-2 infection. PubMed, Web of Science, Scopus, Cochrane Library and Google Scholar were searched to January 1st, 2023. ROBINS-I was used to assess risk of bias of included studies. The outcome of interest was the risk of SARS-COV-2 infection in patients and odds ratio (OR) with 95% confidence interval (95% CI) were calculated using Comprehensive Meta-analysis software version 3. RESULTS: Twelve studies involving seven observational cohort studies, three case-control studies, and two cross-sectional studies were included in this meta-analysis. Overall, compared to non-ICS use, the pooled odds ratio (OR) of the risk of SARS-COV-2 infection was 0.997 (95% confidence interval [CI] 0.664-1.499; p = 0.987) for patients with ICS use. Subgroup analyses demonstrated no statistical significance in the increased risk of SARS-COV-2 infection in patients with ICS monotherapy or in combination with bronchodilators (pooled OR=1.408; 95% CI=0.693-2.858; p = 0.344 in ICS monotherapy, and pooled OR=1.225; 95% CI=0.533-2.815; p = 0.633 in ICS combination, respectively). In addition, no significant association was observed between ICS use and the risk of SARS-COV-2 infection for patients with COPD (pooled OR=0.715; 95% CI=0.415-1.230; p = 0.225) and asthma (pooled OR=1.081; 95% CI=0.970-1.206; p = 0.160). CONCLUSIONS: The use of ICS, either monotherapy or in combination with bronchodilators, does not have impact on the risk of SARS-COV-2 infection.

Efficient recall of SARS-CoV-2 variant-reactive B cells and T responses in the elderly upon heterologous mRNA vaccines as boosters.

Waning antibody levels against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the emergence of variants of concern highlight the need for booster vaccinations. This is particularly important for the elderly population, who are at a higher risk of developing severe coronavirus disease 2019 (COVID-19) disease. While studies have shown increased antibody responses following booster vaccination, understanding the changes in T and B cell compartments induced by a third vaccine dose remains limited. We analyzed the humoral and cellular responses in subjects who received either a homologous messenger RNA(mRNA) booster vaccine (BNT162b2 + BNT162b2 + BNT162b2; ''BBB") or a heterologous mRNA booster vaccine (BNT162b2 + BNT162b2 + mRNA-1273; ''BBM") at Day 0 (prebooster), Day 7, and Day 28 (postbooster). Compared with BBB, elderly individuals (≥60 years old) who received the BBM vaccination regimen display higher levels of neutralizing antibodies against the Wuhan and Delta strains along with a higher boost in immunoglobulin G memory B cells, particularly against the Omicron variant. Circulating T helper type 1(Th1), Th2, Th17, and T follicular helper responses were also increased in elderly individuals given the BBM regimen. While mRNA vaccines increase antibody, T cell, and B cell responses against SARS-CoV-2 1 month after receiving the third dose booster, the efficacy of the booster vaccine strategies may vary depending on age group and regimen combination.

Biphenyl furanocoumarin compounds inhibit SARS-CoV-2 spike pseudovirus infection by binding ACE2

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), is a highly infectious disease with a significant impact on global public health security, and the development of effective antiviral drugs is warranted. In this study, based on HEK293 membrane chromatography (CMC) model that overexpresses angiotensin-converting enzyme 2 (ACE2), we screened six compounds with long retention time on ACE2h/CMC, namely BU-1 to BU-6, from the biphenyl furanocoumarin compounds previously synthesized by our team. The binding properties of the screened compounds to ACE2 were investigated by frontier analysis. Cytotoxicity assay, virtual molecular docking assay and pseudo-viral invasion assay were used to examine the affinity and potential antiviral activity of the selected compounds towards ACE2 protein. The virtual molecular docking results showed that BU-1, BU-2 and BU-5 could form significant hydrogen bonds with hotspot amino acid residues on the ACE2 receptor. And BU-1, BU-2 and BU-5 significantly inhibited the ability of SARS-COV-2 pseudovirus to enter ACE2h cells. Therefore, BU-1, BU-2 and BU-5 have the potential to be used as lead compounds for further modification to develop more effective anti-SARS-CoV-2 drugs. [ FROM AUTHOR]

Irradiation accelerates SARS-CoV-2 infection by enhancing sphingolipid metabolism.

Cancer patients who receive radiotherapy have a high risk of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection, but the concrete reason remains unclear. Herein, we investigated the influence of irradiation on the vulnerability of cancer cells to SARS-CoV-2 using S pseudovirions and probed the underlying mechanism via RNA-seq and other molecular biology techniques. Owing to the enhancement of sphingolipid metabolism, irradiation accelerated pseudovirion infection. Mechanistically, irradiation induced the expression of acid sphingomyelinase (ASM), which catalyses the hydrolysis of sphingomyelin to ceramide, contributing to lipid raft formation and promoting SARS-CoV-2 invasion. Inhibition of lipid raft formation with methyl-ß-cyclodextrin (MßCD) or the tyrosine kinase inhibitor genistein and ASM suppression through small interfering RNA or amitriptyline (AMT) treatment abolished the enhancing effect of irradiation on viral infection. Animal experiments supported the finding that irradiation promoted SARS-CoV-2 S pseudovirion infection in A549 cell tumour-bearing BALB/c nude mice, whereas AMT treatment dramatically decreased viral infection. This study discloses the role of sphingolipid metabolism in irradiation-induced SARS-CoV-2 infection, thus providing a potential target for clinical intervention to protect patients receiving radiotherapy from COVID-19.

γ-Core Guided Antibiotic Design Based on Human Enteric Defensin 5.

An increase in the number of infections caused by resistant bacteria worldwide necessitates the development of alternatives to antibiotics. Human defensin (HD) 5 is an innate immune peptide with broad-spectrum antibacterial activity, but its complicated structure makes its preparation difficult. Herein, we truncated the HD5 structure by extracting the highly conserved γ-core motif. A structure-activity study showed that this motif was ineffective in killing bacteria in the absence of specific spatial conformation. Notably, after the introduction of two intramolecular disulfide bonds, its antibacterial activity was markedly improved. Glu and Ser residues were then replaced with Arg to create the derivative RC18, which exhibited stronger potency than HD5, particularly against methicillin-resistant S. aureus (MRSA). Mechanistically, RC18 bound to lipid A and lipoteichoic acid at higher affinities than HD5. Furthermore, RC18 was more efficient than HD5 in penetrating the bacterial membranes. Molecular dynamics simulation revealed that five Arg residues, Arg1, Arg7, Arg9, Arg15, and Arg18, mediated most of the polar interactions of RC18 with the phospholipid head groups during membrane penetration. In vivo experiments indicated that RC18 decreased MRSA colonization and dramatically improved the survival of infected mice, thus demonstrating that RC18 is a promising drug candidate to treat MRSA infections.

WWOX activates autophagy to alleviate lipopolysaccharide-induced acute lung injury by regulating mTOR.

Acute lung injury (ALI) is characterized by acute systemic inflammatory responses that may lead to severe acute respiratory distress syndrome (ARDS). The clinical course of ALI/ARDS is variable; however, it has been reported that lipopolysaccharides (LPS) play a role in its development. The fragile chromosomal site gene WWOX is highly sensitive to genotoxic stress induced by environmental exposure and is an important candidate gene for exposure-related lung disease research. However, the expression of WWOX and its role in LPS-induced ALI still remain unidentified. This study investigated the expression of WWOX in mouse lung and epithelial cells and explored the role of WWOX in LPS-induced ALI model in vitro and in vivo. In addition, we explored one of the possible mechanisms by which WWOX alleviates ALI from the perspective of autophagy. Here, we observed that LPS stimulation reduced the expression of WWOX and the autophagy marker microtubule-associated protein 1 light chain 3ß-II (MAP1LC3B/LC3B) in mouse lung epithelial and human epithelial (H292) cells. Overexpression of WWOX led to the activation of autophagy and inhibited inflammatory responses in LPS-induced ALI cells and mouse model. More importantly, we found that WWOX interacts with mechanistic target of rapamycin [serine/threonine kinase] (mTOR) and regulates mTOR and ULK-1 signaling-mediated autophagy. Thus, reduced WWOX levels were associated with LPS-induced ALI. WWOX can activate autophagy in lung epithelial cells and protect against LPS-induced ALI, which is partly related to the mTOR-ULK1 signaling pathway.

Chemical profile of anti-epidemic sachet based on multiple sample preparation coupled with gas chromatography-mass spectrometry analysis combined with an embedded peaks resolution method and their action mechanisms.

The anti-epidemic sachet (Fang Yi Xiang Nang, FYXN) in traditional Chinese medicine (TCM) can prevent COVID-19 through volatile compounds that can play the role of fragrant and dampness, heat-clearing and detoxifying, warding off filth and pathogenic factors. Nevertheless, the anti-(mutant) SARS-CoV-2 compounds and the compounds related to the mechanism in vivo, and the mechanism of FYXN are still vague. In this study, the volatile compound set of FYXN was constructed by gas chromatography-mass spectrometry (GC-MS) based on multiple sample preparation methods, which include headspace (HS), headspace solid phase microextraction (HS-SPME) and pressurized liquid extraction (PLE). In addition, selective ion analysis (SIA) was used to resolve embedded chromatographic peaks present in HS-SPME results. Preliminary analysis of active compounds and mechanism of FYXN by network pharmacology combined with disease pathway information based on GC-MS results. A total of 96 volatile compounds in FYXN were collected by GC-MS analysis. 39 potential anti-viral compounds were screened by molecular docking. 13 key pathways were obtained by KEGG pathway analysis (PI3K-Akt signaling pathway, HIF-1 signaling pathway, etc.) for FYXN to prevent COVID-19. 16 anti-viral compounds (C95, C91, etc.), 10 core targets (RELA, MAPK1, etc.), and 16 key compounds related to the mechanism in vivo (C56, C30, etc.) were obtained by network analysis. The relevant pharmacological effects of key pathways and key compounds were verified by the literature. Finally, molecular docking was used to verify the relationship between core targets and key compounds, which are related to the mechanism in vivo. A variety of sample preparation methods coupled with GC-MS analysis combined with an embedded peaks resolution method and integrated with network pharmacology can not only comprehensively characterize the volatile compounds in FYXN, but also expand the network pharmacology research ideas, and help to discover the active compounds and mechanisms in FYXN.

Cucurbitacin B: A review of its pharmacology, toxicity, and pharmacokinetics.

Cucurbitacin B (CuB, C32H46O8), the most abundant and active member of cucurbitacins, which are highly oxidized tetracyclic triterpenoids. Cucurbitacins are widely distributed in a variety of plants and mainly isolated from plants in the Cucurbitaceae family. CuB is mostly obtained from the pedicel of Cucumis melo L. Modern pharmacological studies have confirmed that CuB has a broad range of pharmacological activities, with significant therapeutic effects on a variety of diseases including inflammatory diseases, neurodegenerative diseases, diabetes mellitus, and cancers. In this study the PubMed, Web of Science, Science Direct, and China National Knowledge Infrastructure (CNKI) databases were searched from 1986 to 2022. After inclusion and exclusion criteria were applied, 98 out of 2484 articles were selected for a systematic review to comprehensively summarize the pharmacological activity, toxicity, and pharmacokinetic properties of CuB. The results showed that CuB exhibits potent anti-inflammatory, antioxidant, antiviral, hypoglycemic, hepatoprotective, neuroprotective, and anti-cancer activities mainly via regulating various signaling pathways, such as the Janus kinase/signal transducer and activator of transcription-3 (JAK/STAT3), nuclear factor erythroid 2-related factor-2/antioxidant responsive element (Nrf2/ARE), nuclear factor (NF)-κB, AMP-activated protein kinase (AMPK), mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K)/Akt, cancerous inhibitor of protein phosphatase-2A/protein phosphatase-2A (CIP2A/PP2A), Wnt, focal adhesion kinase (FAK), Notch, and Hippo-Yes-associated protein (YAP) pathways. Studies of its toxicity and pharmacokinetic properties showed that CuB has non-specific toxicity and low bioavailability. In addition, derivatives and clinical applications of CuB are discussed in this paper.

Long-term sequelae of different COVID-19 variants: The original strain versus the Omicron variant.

Although Omicron appears to cause less severe acute illness than the original strain, the potential for large numbers of patients to experience long COVID is a major concern. Little is known about the recovery phase in cases of Omicron, highlighting the importance of dynamically monitor long COVID in those patients. Subjects of the current study were patients available for a three-month follow-up who were admitted from January 13 to May 22, 2020 (period of the original strain) and from January 1 to May 30, 2022 (period of Omicron). Twenty-eight-point-four percent of patients infected with the original strain had long-term symptoms of COVID-19 and 5.63% of those infected with the Omicron strain had such symptoms. The most common symptom was a cough (18.5%), followed by tightness in the chest (6.5%), in patients infected with the original strain. Fatigue (2.4%) and dyspnea (1.7%) were the most commonly reported symptoms in patients infected with the Omicron strain. The respiratory system is the primary target of SARSCoV-2. Supportive treatment is the basis for the treatment of respiratory symptoms in patients with COVID-19. Quality sleep and good nutrition may alleviate fatigue and mental issues. Further knowledge about a long-term syndrome due to Omicron needs to be discussed and assembled so that healthcare and workforce planners can rapidly obtain information to appropriately allocate resources.

Epidemiological characteristics and quarantine assessment of imported international COVID-19 cases, March to December 2020, Chengdu, China.

International flights have accelerated the global spread of Coronavirus Disease 2019 (COVID-19). Determination of the optimal quarantine period for international travelers is crucial to prevent the local spread caused by imported COVID-19 cases. We performed a retrospective epidemiological study using 491 imported COVID-19 cases in Chengdu, China, to describe the characteristic of the cases and estimate the time from arrival to confirmation for international travelers using nonparametric survival methods. Among the 491 imported COVID-19 cases, 194 (39.5%) were asymptomatic infections. The mean age was 35.6 years (SD = 12.1 years) and 83.3% were men. The majority (74.1%) were screened positive for SARS-CoV-2, conducted by Chengdu Customs District, the People's Republic of China. Asymptomatic cases were younger than presymptomatic or symptomatic cases (P < 0.01). The daily number of imported COVID-19 cases displayed jagged changes. 95% of COVID-19 cases were confirmed by PT-PCR within 14 days (95% CI 13-15) after arriving in Chengdu. A 14-day quarantine measure can ensure non-infection among international travelers with a 95% probability. Policymakers may consider an extension of the quarantine period to minimize the negative consequences of the COVID-19 confinement and prevent the international spread of COVID-19. Nevertheless, the government should consider the balance between COVID-19 and socioeconomic development, which may cause more serious social and health crises.

Waning of specific antibodies against Delta and Omicron variants five months after a third dose of BNT162b2 SARS-CoV-2 vaccine in elderly individuals

The emergence of new SARS-CoV-2 variants, such as the more transmissible Delta and Omicron variants, has raised concerns on efficacy of the COVID-19 vaccines. Here, we examined the waning of antibody responses against different variants following primary and booster vaccination. We found that antibody responses against variants were low following primary vaccination. The antibody response against Omicron was almost non-existent. Efficient boosting of antibody response against all variants, including Omicron, was observed following a third dose. The antibody response against the variants tested was significantly higher at one month following booster vaccination, compared with two months following primary vaccination, for all individuals, including the low antibody responders identified at two months following primary vaccination. The antibody response, for all variants tested, was significantly higher at four months post booster than at five months post primary vaccination, and the proportion of low responders remained low (6-11%). However, there was significant waning of antibody response in more than 95% of individuals at four months, compared to one month following booster. We also observed a robust memory B cell response following booster, which remained higher at four months post booster than prior to booster. However, the memory B cell responses were on the decline for 50% of individuals at four months following booster. Similarly, while the T cell response is sustained, at cohort level, at four months post booster, a substantial proportion of individuals (18.8 – 53.8%) exhibited T cell response at four months post booster that has waned to levels below their corresponding levels before booster. The findings show an efficient induction of immune response against SARS-CoV-2 variants following booster vaccination. However, the induced immunity by the third BNT162b2 vaccine dose was transient. The findings suggest that elderly individuals may require a fourth dose to provide protection against SARS-CoV-2.

Multiple-Molecule Drug Repositioning for Disrupting Progression of SARS-CoV-2 Infection by Utilizing the Systems Biology Method through Host-Pathogen-Interactive Time Profile Data and DNN-Based DTI Model with Drug Design Specifications

The coronavirus disease 2019 (COVID-19) pandemic has claimed many lives since it was first reported in late December 2019. However, there is still no drug proven to be effective against the virus. In this study, a candidate host-pathogen-interactive (HPI) genome-wide genetic and epigenetic network (HPI-GWGEN) was constructed via big data mining. The reverse engineering method was applied to investigate the pathogenesis of SARS-CoV-2 infection by pruning the false positives in candidate HPI-GWGEN through the HPI RNA-seq time profile data. Subsequently, using the principal network projection (PNP) method and the annotations of the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, we identified the significant biomarkers usable as drug targets for destroying favorable environments for the replication of SARS-CoV-2 or enhancing the defense of host cells against it. To discover multiple-molecule drugs that target the significant biomarkers (as drug targets), a deep neural network (DNN)-based drug-target interaction (DTI) model was trained by DTI databases to predict candidate molecular drugs for these drug targets. Using the DNN-based DTI model, we predicted the candidate drugs targeting the significant biomarkers (drug targets). After screening candidate drugs with drug design specifications, we finally proposed the combination of bosutinib, erlotinib, and 17-beta-estradiol as a multiple-molecule drug for the treatment of the amplification stage of SARS-CoV-2 infection and the combination of erlotinib, 17-beta-estradiol, and sertraline as a multiple-molecule drug for the treatment of saturation stage of mild-to-moderate SARS-CoV-2 infection.