Tissue and Plasma-Based Highly Sensitive Blocker Displacement Amplicon Nanopore Sequencing for EGFR Mutations in Lung Cancer

PURPOSE

The epidermal growth factor receptor (EGFR) mutation is a widely prevalent oncogene driver in non-small cell lung cancer (NSCLC) in East Asia. The detection of EGFR mutations is a standard biomarker test performed routinely in patients with NSCLC for the selection of targeted therapy. Here, our objective was to develop a portable new technique for detecting EGFR (19Del, T790M, and L858R) mutations based on Nanopore sequencing.

MATERIALS AND METHODS

The assay employed a blocker displacement amplification (BDA)-based polymerase chain reaction (PCR) technique combined with Nanopore sequencing to detect EGFR mutations. Mutant and wild-type EGFR clones were generated from DNA from H1650 (19Del heterozygous) and H1975 (T790M and L858R heterozygous) lung cancer cell lines. Then, they were mixed to assess the performance of this technique for detecting low variant allele frequencies (VAFs). Subsequently, formalin-fixed, paraffin-embedded (FFPE) tissue and cell-free DNA (cfDNA) from patients with NSCLC were used for clinical validation.

RESULTS

The assay can detect low VAF at 0.5% mutant mixed in wild-type EGFR. Using FFPE DNA, the concordance rates of EGFR 19Del, T790M, and L858R mutations between our method and Cobas real-time PCR were 98.46%, 100%, and 100%, respectively. For cfDNA, the concordance rates of EGFR 19Del, T790M, and L858R mutations between our method and droplet digital PCR were 94.74%, 100%, and 100%, respectively.

CONCLUSION

The BDA amplicon Nanopore sequencing is a highly accurate and sensitive method for the detection of EGFR mutations in clinical specimens.

First report of blaOXA-181-carrying IncX3 plasmids in multidrug-resistant Enterobacter hormaechei and Serratia nevei recovered from canine and feline opportunistic infections

Whole-genome sequence analysis of six Enterobacter hormaechei and two Serratia nevei strains, using a hybrid assembly of Illumina and Oxford Nanopore Technologies sequencing, revealed the presence of the epidemic blaOXA-181-carrying IncX3 plasmids co-harboring qnrS1 and ∆ere(A) genes, as well as multiple multidrug resistance (MDR) plasmids disseminating in all strains, originated from dogs and cats in Thailand. The subspecies and sequence types (ST) of the E. hormaechei strains recovered from canine and feline opportunistic infections included E. hormaechei subsp. xiangfangensis ST171 (n = 3), ST121 (n = 1), and ST182 (n = 1), as well as E. hormaechei subsp. steigerwaltii ST65 (n = 1). Five of the six E. hormaechei strains harbored an identical 51,479-bp blaOXA-181-carrying IncX3 plasmid. However, the blaOXA-181 plasmid (pCUVET22-969.1) of the E. hormaechei strain CUVET22-969 presented a variation due to the insertion of ISKpn74 and ISSbo1 into the virB region. Additionally, the blaOXA-181 plasmids of S. nevei strains were nearly identical to the others at the nucleotide level, with ISEcl1 inserted upstream of the qnrS1 gene. The E. hormaechei and S. nevei lineages from canine and feline origins might acquire the epidemic blaOXA-181-carrying IncX3 and MDR plasmids, which are shared among Enterobacterales, contributing to the development of resistance. These findings suggest the spillover of significant OXA-181-encoding plasmids to these bacteria, causing severe opportunistic infections in dogs and cats in Thailand. Surveillance and effective hygienic practice, especially in hospitalized animals and veterinary hospitals, should be urgently implemented to prevent the spread of these plasmids in healthcare settings and communities.

IMPORTANCE

blaOXA-181 is a significant carbapenemase-encoding gene, usually associated with an epidemic IncX3 plasmid found in Enterobacterales worldwide. In this article, we revealed six carbapenemase-producing (CP) Enterobacter hormaechei and two CP Serratia nevei strains harboring blaOXA-181-carrying IncX3 and multidrug resistance plasmids recovered from dogs and cats in Thailand. The carriage of these plasmids can promote extensively drug-resistant properties, limiting antimicrobial treatment options in veterinary medicine. Since E. hormaechei and S. nevei harboring blaOXA-181-carrying IncX3 plasmids have not been previously reported in dogs and cats, our findings provide the first evidence of dissemination of the epidemic plasmids in these bacterial species isolated from animal origins. Pets in communities can serve as reservoirs of significant antimicrobial resistance determinants. This situation places a burden on antimicrobial treatment in small animal practice and poses a public health threat.

Single-Drop Blood Detection of Common G6PD Mutations in Thailand Based on Allele-Specific Recombinase Polymerase Amplification with CRISPR-Cas12a

Glucose 6-phosphate dehydrogenase (G6PD) deficiency is the most common inherited enzymopathy. Identification of the G6PD deficiency through screening is crucial to preventing adverse effects associated with hemolytic anemia following antimalarial drug exposure. Therefore, a rapid and precise field-based G6PD deficiency diagnosis is required, particularly in rural regions where malaria is prevalent. The phenotypic diagnosis of the G6PD intermediate has also been a challenging issue due to the overlapping of G6PD activity levels between deficient and normal individuals, leading to a misinterpretation. The availability of an accurate point-of-care testing (POCT) for G6PD genotype diagnosis will therefore increase the opportunity for screening heterozygous cases in a low-resource setting. In this study, an allele-specific recombinase polymerase amplification (AS RPA) with clustered regularly interspaced short palindromic repeats-Cas12a (CRISPR-Cas12a) was developed as a POCT for accurate diagnosis of common G6PD mutations in Thailand. The AS primers for the wild type and mutant alleles of G6PD MahidolG487A and G6PD ViangchanG871A were designed and used in RPA reactions. Following application of CRISPR-Cas12a systems containing specific protospacer adjacent motif, the targeted RPA amplicons were visualized with the naked eye. Results demonstrated that the G6PD MahidolG487A and G6PD ViangchanG871A assays reached 93.62 and 98.15% sensitivity, respectively. The specificity was 88.71% in MahidolG487A and 99.02% in G6PD ViangchanG871A. The diagnosis accuracy of the G6PD MahidolG487A and G6PD ViangchanG871A assays was 91.67 and 98.72%, respectively. From DNA extraction to detection, the assay required approximately 52 min. In conclusion, this study demonstrated the high performance of an AS RPA with the CRISPR-Cas12a platform for G6PD MahidolG487A and G6PD ViangchanG871A detection assays and the potential use of G6PD genotyping as POCT.

"Nano COVID-19": Nanopore sequencing of spike gene to identify SARS-CoV-2 variants of concern

Coronavirus disease 2019 (COVID-19) is a worldwide pandemic infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). World Health Organization (WHO) has defined the viral variants of concern (VOC) which cause more severe disease, higher transmissibility, and reduced vaccine efficacy. In this study, the "Nano COVID-19" workflow based on Oxford nanopore sequencing of the full-length spike gene combined with flexible data analysis options was developed to identify SARS-CoV-2 VOCs. The primers were designed to cover the full-length spike gene and can amplify all VOC strains. The results of VOC identification based on phylogenetic analysis of the full-length spike gene were comparable to the whole genome sequencing (WGS). Compared to the standard VOC identification pipeline, the fast analysis based on Read Assignment, Mapping, and Phylogenetic Analysis in Real Time (RAMPART) and the user-friendly method based on EPI2ME yielded 89.3% and 97.3% accuracy, respectively. The EPI2ME pipeline is recommended for researchers without bioinformatic skills, whereas RAMPART is more suitable for bioinformaticians. This workflow provides a cost-effective, simplified pipeline with a rapid turnaround time. Furthermore, it is portable to point-of-care SARS-CoV-2 VOC identification and compatible with large-scale analysis. Therefore, "Nano COVID-19" is an alternative viral epidemic screening and transmission tracking workflow.

Ultrarapid and high-resolution HLA class I typing using transposase-based nanopore sequencing applied in pharmacogenetic testing

Nanopore sequencing has been examined as a method for rapid and high-resolution human leukocyte antigen (HLA) typing in recent years. We aimed to apply ultrarapid nanopore-based HLA typing for HLA class I alleles associated with drug hypersensitivity, including HLA-A*31:01, HLA-B*15:02, and HLA-C*08:01. Most studies have used the Oxford Nanopore Ligation Sequencing kit for HLA typing, which requires several enzymatic reactions and remains relatively expensive, even when the samples are multiplexed. Here, we used the Oxford Nanopore Rapid Barcoding kit, which is transposase-based, with library preparation taking less than 1 h of hands-on time and requiring minimal reagents. Twenty DNA samples were genotyped for HLA-A, -B, and -C; 11 samples were from individuals of different ethnicity and nine were from Thai individuals. Two primer sets, a commercial set and a published set, were used to amplify the HLA-A, -B, and -C genes. HLA-typing tools that used different algorithms were applied and compared. We found that without using several third-party reagents, the transposase-based method reduced the hands-on time from approximately 9 h to 4 h, making this a viable approach for obtaining same-day results from 2 to 24 samples. However, an imbalance in the PCR amplification of different haplotypes could affect the accuracy of typing results. This work demonstrates the ability of transposase-based sequencing to report 3-field HLA alleles and its potential for race- and population-independent testing at considerably decreased time and cost.

Investigation of the Molecular Epidemiology and Evolution of Circulating Severe Acute Respiratory Syndrome Coronavirus 2 in Thailand from 2020 to 2022 via Next-Generation Sequencing

Coronavirus disease 2019 (COVID-19) is an infectious condition caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), which surfaced in Thailand in early 2020. The current study investigated the SARS-CoV-2 lineages circulating in Thailand and their evolutionary history. Complete genome sequencing of 210 SARS-CoV-2 samples collected from collaborating hospitals and the Institute of Urban Disease Control and Prevention over two years, from December 2020 to July 2022, was performed using next-generation sequencing technology. Multiple lineage introductions were observed before the emergence of the B.1.1.529 omicron variant, including B.1.36.16, B.1.351, B.1.1, B.1.1.7, B.1.524, AY.30, and B.1.617.2. The B.1.1.529 omicron variant was subsequently detected between January 2022 and June 2022. The evolutionary rate for the spike gene of SARS-CoV-2 was estimated to be between 0.87 and 1.71 × 10^-3 substitutions per site per year. There was a substantial prevalence of the predominant mutations C25672T (L94F), C25961T (T190I), and G26167T (V259L) in the ORF3a gene during the Thailand outbreaks. Complete genome sequencing can enhance the prediction of future variant changes in viral genomes, which is crucial to ensuring that vaccine strains are protective against worldwide outbreaks.

Intrahost Genetic Diversity of Dengue Virus in Human Hosts and Mosquito Vectors under Natural Conditions Which Impact Replicative Fitness In Vitro

Dengue virus (DENV) is an arbovirus whose transmission cycle involves disparate hosts: humans and mosquitoes. The error-prone nature of viral RNA replication drives the high mutation rates, and the consequently high genetic diversity affects viral fitness over this transmission cycle. A few studies have been performed to investigate the intrahost genetic diversity between hosts, although their mosquito infections were performed artificially in the laboratory setting. Here, we performed whole-genome deep sequencing of DENV-1 (n = 11) and DENV-4 (n = 13) derived from clinical samples and field-caught mosquitoes from the houses of naturally infected patients, in order to analyze the intrahost genetic diversity of DENV between host types. Prominent differences in DENV intrahost diversity were observed in the viral population structure between DENV-1 and DENV-4, which appear to be associated with differing selection pressures. Interestingly, three single amino acid substitutions in the NS2A (K81R), NS3 (K107R), and NS5 (I563V) proteins in DENV-4 appear to be specifically acquired during infection in Ae. aegypti mosquitoes. Our in vitro study shows that the NS2A (K81R) mutant replicates similarly to the wild-type infectious clone-derived virus, while the NS3 (K107R), and NS5 (I563V) mutants have prolonged replication kinetics in the early phase in both Vero and C6/36 cells. These findings suggest that DENV is subjected to selection pressure in both mosquito and human hosts. The NS3 and NS5 genes may be specific targets of diversifying selection that play essential roles in early processing, RNA replication, and infectious particle production, and they are potentially adaptive at the population level during host switching.

Enhancing the yield of seasonal influenza viruses through manipulation of microRNAs in Madin-Darby canine kidney cells

Annual influenza vaccine is recommended to reduce the occurrence of seasonal influenza and its complications. Thus far, Madin-Darby canine kidney (MDCK) cell line has been used to manufacture cell-based influenza vaccines. Even though host microRNAs may facilitate viral replication, the interaction between MDCK cells-derived microRNAs and seasonal influenza viruses has been less frequently investigated. Therefore, this study highlighted microRNA profiles of MDCK cells to increase the yield of seasonal influenza virus production by manipulating cellular microRNAs. MDCK cells were infected with influenza A or B virus at a multiplicity of infection (MOI) of 0.01, and microRNA collections were then subjected to MiSeq (Illumina) Sequencing. The validated profiles revealed that cfa-miR-340, cfa-miR-146b, cfa-miR-197, and cfa-miR-215 were the most frequently upregulated microRNAs. The effect of candidate microRNA inhibition and overexpression on viral replication was determined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA). The hybridization pattern between candidate miRNAs and viral genes was performed using miRBase and RNAhybrid web-based programs. Moreover, the predicted microRNA-binding sites were validated by a 3'-UTR reporter assay. The results indicated that cfa-miR-146b could directly target the PB1 gene of A/pH1N1 and the PA gene of B/Yamagata. Furthermore, cfa-miR-215 could silence the PB1 gene of A/pH1N1 and the PB1 gene of B/Victoria. However, the PB2 gene of the A/H3N2 virus was silenced by cfa-miR-197. In addition, the HA and NA sequences of influenza viruses harvested from the cell cultures treated with microRNA inhibitors were analyzed. The sequencing results revealed no difference in the antigenic HA and NA sequences between viruses isolated from the cells treated with microRNA inhibitors and the parental viruses. In conclusion, these findings suggested that MDCK cell-derived microRNAs target viral genes in a strain-specific manner for suppressing viral replication. Conversely, the use of such microRNA inhibitors may facilitate the production of influenza viruses.

COVID-19 active case findings based on self-collected saliva samples with CRISPR-Cas12a detection

COVID-19 is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus affecting the world population. Early detection has become one of the most successful strategies to alleviate the epidemic and pandemic of this contagious coronavirus. Surveillance testing programs have been initiated in many countries worldwide to prevent the outbreak of COVID-19. In this study, we demonstrated that our previously established clustered regularly interspaced short palindromic repeats (CRISPR)-Cas12a-based assay could detect variants of concern during 2021 in Thailand, including Alpha, Beta, and Delta strains as well as Omicron strain in early 2022. In combination with the newly designed saliva collection funnel, we established a safe, simple, economical, and efficient self-collection protocol for the COVID-19 screening process. We successfully utilized the assay in an active case finding with a total number of 578 asymptomatic participants to detect the SARS-CoV-2 in saliva samples. We finally demonstrated that the validation and evaluation in a large-scale setting could provide valuable information and elaborate the practicality of the test in real-world settings. Our optimized protocol yielded effective results with high sensitivity, specificity, and diagnostic accuracy (96.86%). In addition, this study demonstrates COVID-19 active case findings in low-resource settings, which would be feasible and attractive for surveillance and outbreak prevention in the future.

Metagenomic analysis of the gut microbiota in piglets either challenged or not with enterotoxigenic Escherichia coli reveals beneficial effects of probiotics on microbiome composition, resistome, digestive function and oxidative stress responses

This study used metagenomic analysis to investigate the gut microbiota and resistome in piglets that were or were not challenged with enterotoxigenic Escherichia coli (ETEC) and had or had not received dietary supplementation with microencapsulated probiotics. The 72 piglets belonged to six groups that were either non-ETEC challenged (groups 1–3) or ETEC challenged (receiving 5ml of 10⁹ CFU/ml pathogenic ETEC strain L3.2 one week following weaning at three weeks of age: groups 4–6). On five occasions at 2, 5, 8, 11, and 14 days of piglet age, groups 2 and 5 were supplemented with 10⁹ CFU/ml of multi-strain probiotics (Lactiplantibacillus plantarum strains 22F and 25F, and Pediococcus acidilactici 72N) while group 4 received 10⁹ CFU/ml of P. acidilactici 72N. Group 3 received 300mg/kg chlortetracycline in the weaner diet to mimic commercial conditions. Rectal faecal samples were obtained for metagenomic and resistome analysis at 2 days of age, and at 12 hours and 14 days after the timing of post-weaning challenge with ETEC. The piglets were all euthanized at 42 days of age. The piglets in groups 2 and 5 were enriched with several desirable microbial families, including Lactobacillaceae, Lachnospiraceae and Ruminococcaceae, while piglets in group 3 had increases in members of the Bacteroidaceae family and exhibited an increase in tetW and tetQ genes. Group 5 had less copper and multi-biocide resistance. Mobile genetic elements IncQ1 and IncX4 were the most prevalent replicons in antibiotic-fed piglets. Only groups 6 and 3 had the integrase gene (intl) class 2 and 3 detected, respectively. The insertion sequence (IS) 1380 was prevalent in group 3. IS3 and IS30, which are connected to dietary intake, were overrepresented in group 5. Furthermore, only group 5 showed genes associated with detoxification, with enrichment of genes associated with oxidative stress, glucose metabolism, and amino acid metabolism compared to the other groups. Overall, metagenomic analysis showed that employing a multi-strain probiotic could transform the gut microbiota, reduce the resistome, and boost genes associated with food metabolism.

Genome characterization and mutation analysis of human influenza A virus in Thailand

The influenza A viruses have high mutation rates and cause a serious health problem worldwide. Therefore, this study focused on genome characterization of the viruses isolated from Thai patients based on the next-generation sequencing technology. The nasal swabs were collected from patients with influenza-like illness in Thailand during 2017-2018. Then, the influenza A viruses were detected by reverse transcription-quantitative polymerase chain reaction and isolated by MDCK cells. The viral genomes were amplified and sequenced by Illumina MiSeq platform. Whole genome sequences were used for characterization, phylogenetic construction, mutation analysis and nucleotide diversity of the viruses. The result revealed that 90 samples were positive for the viruses including 44 of A/H1N1 and 46 of A/H3N2. Among these, 43 samples were successfully isolated and then the viral genomes of 25 samples were completely amplified. Finally, 17 whole genomes of the viruses (A/H1N1, n=12 and A/H3N2, n=5) were successfully sequenced with an average of 232,578 mapped reads and 1,720 genome coverage per sample. Phylogenetic analysis demonstrated that the A/H1N1 viruses were distinguishable from the recommended vaccine strains. However, the A/H3N2 viruses from this study were closely related to the recommended vaccine strains. The nonsynonymous mutations were found in all genes of both viruses, especially in HA and NA genes. The nucleotide diversity analysis revealed negative selection in the PB1, PA, hemagglutinin (HA) and neuraminidase (NA) genes of the A/H1N1 viruses. High-throughput data in this study allow for genetic characterization of circulating influenza viruses which would be crucial for preparation against pandemic and epidemic outbreaks in the future.

A Sensitive and Specific Fluorescent RT-LAMP Assay for SARS-CoV-2 Detection in Clinical Samples

The raging COVID-19 pandemic has created an unprecedented demand for frequent and widespread testing to limit viral transmission. Reverse transcription loop-mediated isothermal amplification (RT-LAMP) has emerged as a promising diagnostic platform for rapid detection of SARS-CoV-2, in part because it can be performed with simple instrumentation. However, isothermal amplification methods frequently yield spurious amplicons even in the absence of a template. Consequently, RT-LAMP assays can produce false positive results when they are based on generic intercalating dyes or pH-sensitive indicators. Here, we report the development of a sensitive RT-LAMP assay that leverages on a novel sequence-specific probe to guard against spurious amplicons. We show that our optimized fluorescent assay, termed LANTERN, takes only 30 min to complete and can be applied directly on swab or saliva samples. Furthermore, utilizing clinical RNA samples from 52 patients with COVID-19 infection and 21 healthy individuals, we demonstrate that our diagnostic test exhibits a specificity and positive predictive value of 95% with a sensitivity of 8 copies per reaction. Hence, our new probe-based RT-LAMP assay can serve as an inexpensive method for point-of-need diagnosis of COVID-19 and other infectious diseases.

Bacterial microbiota in upper respiratory tract of COVID-19 and influenza patients

The upper respiratory tract is inhabited by diverse range of commensal microbiota which plays a role in protecting the mucosal surface from pathogens. Alterations of the bacterial community from respiratory viral infections could increase the susceptibility to secondary infections and disease severities. We compared the upper respiratory bacterial profiles among Thai patients with influenza or COVID-19 by using 16S rDNA high-throughput sequencing based on MiSeq platform. The Chao1 richness was not significantly different among groups, whereas the Shannon diversity of Flu A and Flu B groups were significantly lower than Non-Flu & COVID-19 group. The beta diversity revealed that the microbial communities of influenza (Flu A and Flu B), COVID-19, and Non-Flu & COVID-19 were significantly different; however, the comparison of the community structure was similar between Flu A and Flu B groups. The bacterial classification revealed that Enterobacteriaceae was predominant in influenza patients, while Staphylococcus and Pseudomonas were significantly enriched in the COVID-19 patients. These implied that respiratory viral infections might be related to alteration of upper respiratory bacterial community and susceptibility to secondary bacterial infections. Moreover, the bacteria that observed in Non-Flu & COVID-19 patients had high abundance of Streptococcus, Prevotella, Veillonella, and Fusobacterium. This study provides the basic knowledge for further investigation of the relationship between upper respiratory microbiota and respiratory disease which might be useful for better understanding the mechanism of viral infectious diseases.

Hepatitis B Virus-Encoded MicroRNA (HBV-miR-3) Regulates Host Gene PPM1A Related to Hepatocellular Carcinoma

BACKGROUND

Hepatitis B is a liver infection disease caused by the Hepatitis B Virus (HBV) that can become chronic and develop into hepatocellular carcinoma. HBV was classified as a double-stranded DNA virus. Currently, there is a report showing that HBV virus-encoded miRNA called HBV-miR-3 controls the replication of HBV. However, the regulation of HBV-miR-3 in host cells remains unclear.

OBJECTIVE

This study aimed to investigate the regulation of HBV-miR-3 in host gene target which is related to chronic HBV infection and HCC process.

METHODS

In this study, we analyzed the read count of HBV-miR-3 from next-generation sequencing of chronic hepatitis patients in Pegylated interferon alpha-2a (PEG-IFN-α-2a) treatment. To understand the regulation of HBV-miR-3 in host cells, the HBV-miR-3 recognition sites were predicted in host target genes using miRDB. The effect of HBV-miR-3 in host cells was examined using qPCR and 3' UTR dual luciferase assay.

RESULTS

The read count of HBV-miR-3 was found in chronic hepatitis patients before treatment. Moreover, the decrease of HBV-miR-3 was correlated with response group of chronic hepatitis patients after treatment. On the other hand, the abundance of HBV-miR-3 showed no difference in nonresponse group of chronic patients after PEG-IFN-α-2a treatment. To study the role of HBV-miR-3 in patients, four HBV-miR-3 target regions from Protein phosphatase 1A (PPM1A) and DIX domain containing 1 (DIXDC1) were identified in the human genome using miRDB. Interestingly, we found that HBV-miR-3 hybridized with PPM1A mRNA. The mRNA expression from RT-qPCR showed no difference between HepG2 transfected with pSilencer_scramble or pSilencer_HBV-miR-3. However, the reporter assay showed that PPM1A mRNA was suppressed by HBV-miR-3. The protein expression of PPM1A showed a decrease in cells overexpressing HBV-miR-3. Finally, the HBV-miR-3 can promote cell proliferation in cells overexpressing HBV-miR-3.

CONCLUSION

This study is the first report showed the HBV encoded miRNA can regulate host gene expression. HBV-miR-3 silenced PPM1A by inhibiting the translation process of PPM1A. The downregulation of PPM1A promotes cell proliferation related to HCC development.

Machine Learning-Driven and Smartphone-Based Fluorescence Detection for CRISPR Diagnostic of SARS-CoV-2

Rapid, accurate, and low-cost detection of SARS-CoV-2 is crucial to contain the transmission of COVID-19. Here, we present a cost-effective smartphone-based device coupled with machine learning-driven software that evaluates the fluorescence signals of the CRISPR diagnostic of SARS-CoV-2. The device consists of a three-dimensional (3D)-printed housing and low-cost optic components that allow excitation of fluorescent reporters and selective transmission of the fluorescence emission to a smartphone. Custom software equipped with a binary classification model has been developed to quantify the acquired fluorescence images and determine the presence of the virus. Our detection system has a limit of detection (LoD) of 6.25 RNA copies/μL on laboratory samples and produces a test accuracy of 95% and sensitivity of 97% on 96 nasopharyngeal swab samples with transmissible viral loads. Our quantitative fluorescence score shows a strong correlation with the quantitative reverse transcription polymerase chain reaction (RT-qPCR) Ct values, offering valuable information of the viral load and, therefore, presenting an important advantage over nonquantitative readouts.

Detection of severe acute respiratory syndrome coronavirus 2 and influenza viruses based on CRISPR-Cas12a

Due to the common symptoms of COVID-19, patients are similar to influenza-like illness. Therefore, the detection method would be crucial to discriminate between SARS-CoV-2 and influenza virus-infected patients. In this study, CRISPR-Cas12a-based detection was applied for detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza A virus, and influenza B virus which would be a practical and attractive application for screening of patients with COVID-19 and influenza in areas with limited resources. The limit of detection for SARS-CoV-2, influenza A, and influenza B detection was 10, 10³, and 10³ copies/reaction, respectively. Moreover, the assays yielded no cross-reactivity against other respiratory viruses. The results revealed that the detection of influenza virus and SARS-CoV-2 by using RT-RPA and CRISPR-Cas12a technology reaches 96.23% sensitivity and 100% specificity for SARS-CoV-2 detection. The sensitivity for influenza virus A and B detections was 85.07% and 94.87%, respectively. In addition, the specificity for influenza virus A and B detections was approximately 96%. In conclusion, the RT-RPA with CRISPR-Cas12a assay was an effective method for the screening of influenza viruses and SARS-CoV-2 which could be applied to detect other infectious diseases in the future.

Hsa-miR-30e-3p inhibits influenza B virus replication by targeting viral NA and NP genes

Influenza B virus is a member of the Orthomyxoviridae family which can infect humans and causes influenza. Although it is not pandemic like influenza A virus, it nevertheless affects millions of people worldwide annually. MicroRNAs are small non-coding RNAs regulating gene expression at posttranscriptional level. They play various important roles in cellular processes including response to viral infection. MiRNA profiles from our previous study suggested that miR-30e-3p was one of the upregulated miRNAs that responded to influenza B virus infection. In this study, in silico prediction and in vitro investigation proved that this miRNA can directly target NA and NP genes of the influenza B virus and inhibit its replication. This finding might be useful for using miRNA as an alternative therapeutics for influenza virus infection.

Diagnostic and prognostic roles of circulating miRNA-223-3p in hepatitis B virus-related hepatocellular carcinoma

Background

Circulating microRNAs (miRNAs) have been shown to dysregulate in many cancer types including hepatocellular carcinoma (HCC). The purpose of this study was to examine the potential diagnostic or prognostic roles of circulating miRNAs in patients with hepatitis B virus (HBV)-related HCC.

Methods

Paired cancerous and adjacent non-cancerous liver tissue specimens of patients with HBV-related HCC were used as a discovery set for screening 800 miRNAs by a Nanostring quantitative assay. Differentially expressed miRNAs were then examined by SYBR green quantitative RT-PCR in a validation cohort of serum samples obtained from 70 patients with HBV-related HCC, 70 HBV patients without HCC and 50 healthy controls.

Results

The discovery set identified miR-223-3p, miR-199a-5p and miR-451a significantly lower expressed in cancerous tissues compared with non-cancerous tissues. In the validated cohort, circulating miR-223-3p levels were significantly lower in the HCC group compared with the other groups. The combined use of serum alpha-fetoprotein and miR-223-3p displayed high sensitivity for detecting early HCC (85%) and intermediate/advanced stage HCC (100%). Additionally, serum miR-223-3p had a negative correlation with tumor size and BCLC stage. On multivariate analysis, serum miR-223-3p was identified as an independent prognostic factor of overall survival in patients with HCC. In contrast, circulating miRNA-199a-5p and miR-451a did not show any clinical benefit for the diagnosis and prognostic prediction of HCC.

Conclusions

Our results demonstrated that miR-223-3p was differentially expressed in cancerous compared with paired adjacent non-cancerous tissues. In addition, circulating miRNA-223-3p could represent a novel diagnostic and prognostic marker for patients with HBV-related HCC.